Elecraft KPA1500 Programming Reference User Guide

Elecraft KPA1500 Programming Reference

Espesifikasyon

• Vèsyon mikrolojisyèl: 03.0 (apati de 6/1/2026)
• Koneksyon seri:
  • XCVR SERIAL connector (can be repurposed as an additional host)
  • Host PC USB connector (for firmware installation)
• Koneksyon rezo:
  • TCP server at port 1500 (default, configurable via ^CP or KPA1500 Utility)
  • UDP server (same port as TCP, single command/response, potential packet discard)
• Concurrent Connections: Host PC USB, XCVR SERIAL HOST, one TCP client, any number of UDP clients.
• ATU Settings Per Bin: 1 to 32 (changed from 31 to 32 in version 3.00).

Itilizasyon Enstriksyon

Connecting to the KPA1500

1. Koneksyon seri: Connect your transceiver to the KPA1500’s XCVR SERIAL connector. This connector can also be configured as an additional host for serial commands.
2. Koneksyon USB: Use the Host PC USB connector primarily for installing KPA1500 firmware.
3. Network Connection (TCP): Connect to the KPA1500 via TCP on port 1500. This port can be changed using the ^CP command or the KPA1500 Utility’s Network tab.
4. Network Connection (UDP): Connect to the KPA1500 via UDP on the same port as the TCP server. Note that UDP is suitable for single command/response interactions and may experience packet loss due to network congestion.

Fòma kòmand

• GET Commands: Used to retrieve information. They result in a RESPONSE message.
• SET Commands: Used to change the KPA1500’s state or initiate actions. They generally do not result in an immediate RESPONSE. You can follow a SET with a GET to verify the change.
• Sentaks: All commands and responses begin with a caret (^) and end with a semicolon (;).
• Example GET: To query the serial number, send ^SN;. The KPA1500 will respond with ^SN00022; (egzanpample).
• Case Sensitivity: Commands are case-insensitive (e.g., ^RV;, ^rv;, ak ^rV; are equivalent). Responses are typically uppercase, except for the boot block’s response to ^I; (^kpa1500;).
• Kontwòl koule: There is no explicit flow control. After sending a GET command, wait for its RESPONSE before sending more commands to avoid overflowing the input buffer. For long sequences of SET commands, intersperse GET commands and wait for responses.
• Fòma: Do not add spaces or omit leading zeros within commands. The semicolon’s position is crucial for command validity and discrimination.

Band Numbers

Many commands use a two-digit band number (bb) as defined by Elecraft’s K-line and KX-line transceivers:

bb	Non Gwoup
00	160 meters (1.8 MHz)
01	80 meters (3.5 MHz)
02	60 meters (5 MHz)
03	40 meters (7 MHz)
04	30 meters (10.1 MHz)
05	20 meters (14 MHz)
06	17 meters (18.068 MHz)
07	15 meters (21 MHz)
08	12 meters (24.89 MHz)
09	10 meters (28 MHz)
10	6 meters (50 MHz)

Antenna Numbers

The KPA1500 has ANT1 and ANT2 connectors. Some commands use antenna number 0 to refer to both, the other, or the most recently used antenna connector.

Testing Commands

• KPA1500 Utility: Use the “Command Tester” tab in the KPA1500 Utility. Type a command (e.g., ^RV;) into the input area, and the command and its response will appear in the output area.
• PuTTY: PuTTY (available from www.putty.org) or other terminal emulators can be used for direct serial or network communication.

Wake-on-LAN

If the “NET WAKE on LAN” menu item is enabled, the KPA1500 can be awakened by sending a magic packet (refer to Wake-on-LAN – Wikipedia for details).

Example Kòmandman

• Null Command: ; (single semicolon). Used by KPA1500 Utility for serial speed detection and waking a sleeping KPA1500.
• ATU Mode Switch: ^AA
• ATU Settings Per Bin (current band):
  • JWENN: ^AB;
  • SET/RESPONSE: ^ABnn; (kote nn is 1-32)
• ATU Settings Per Bin (specified band): ^ABbbnn; (kote bb is band number, nn is 1-32)

Depanaj

• No Response to Commands:
  • Ensure correct command syntax (leading caret, terminating semicolon, no extra spaces).
  • Verify the KPA1500 is powered on and not in a sleep state.
  • Check the connection type (serial, USB, TCP, UDP) and ensure the correct port/settings are used.
  • If using UDP, be aware that packets may be discarded due to network congestion.
  • If sending multiple commands quickly, try inserting a GET command and waiting for its response to prevent buffer overflow.
• Incorrect Response:
  • Double-check the command sent.
  • Ensure the firmware version supports the command and its expected behavior (e.g., ATU settings per bin changed in v3.00).
• Pwoblèm Mizajou Firmware: Use the Host PC USB connector for all firmware installations.
• Pwoblèm Koneksyon Rezo:
  • Verify the IP address and port number.
  • Check network cables and router settings.
  • If the default TCP port 1500 was changed, ensure your client is connecting to the new port.

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Plis paseview

KPA1500 commands and their responses use the ASCII character set. Commands are sent to the KPA1500 via its “Host PC” USB connector, which incorporates a USB-to-serial adapter, and appears as a serial port to a Host PC. Use 4800, 9600, 19200, 38400, 57600, 115200, or 230400 bits per second, 8 data bits, one stop bit, and no parity. There is no automatic flow control; pace commands by waiting for responses. The KPA1500 Utility discovers the Host PC speed by sending a few null commands (semicolons) at each speed until a response is received. You can change the KPA1500 “Host PC” speed with the ^BRP command, or the SERIAL SPEED HOST menu item.
The KPA1500 rear panel XCVR SERIAL connector is normally used for transceiver connection. It may be repurposed to be an additional “host” that accepts this same serial command set. The “Host PC” USB connector must be used to install KPA1500 firmware. See the XCVR SERIAL HOST menu item and the ^XH command description below.
A TCP server at port 1500 accepts the same command set. The default port number may be changed with ^CP or the KPA1500 Utility Edit Configuration Network tab.
A UDP server, using the same port number as the TCP server, accepts the same command set. Send only one command and expect at most one response. UDP packets may be discarded if network congestion occurs.
The Host PC USB connector, XCVR SERIAL HOST, a single TCP client and any number of UDP clients may be concurrently active.
Fòma kòmand
KPA1500 commands are either GET or SET.
GET commands are used to retrieve information from the KPA1500; information is returned in a RESPONSE message.
SET commands are used to change the KPA1500’s internal state or to initiate an action. SET commands do not generally result in a RESPONSE message. SET can be followed by GET to verify the SET. In a few cases, a SET is followed by a delayed response (e.g., an ATU tune operation).
Each command and response begins with a leading caret (^) and ends with a terminating semicolon (;). For example, to query the KPA1500 for its serial number, send GET command ^SN; The KPA1500 responds with its serial number, e.g., ^SN00022;
After sending a GET command, you should generally wait for the corresponding RESPONSE before sending more commands. There is no flow control, and the KPA1500 has a limited size input command buffer. Long strings of SET commands should be broken up with a GET and wait for response.
6

Commands may be entered in UPPER, lower, or MiXeD case. ^RV; ^rv; and ^rV; are equivalent. RESPONSEs are, with one exception, returned in UPPER case. The boot block responds to ^I; in lower case “^kpa1500;”. Commands must be entered as shown. Don’t add spaces or omit leading zeros. The position of the semicolon relative to the leading caret is used for validity checking and to discriminate between various forms of a command.
7

Nimewo Band
Several commands apply to the “current” band, or may apply to a specified band, shown as bb. The band numbers are from the ^BN; command, also used by Elecraft’s K-line and KX-line transceivers:

bb

Non bann

00

160 meters (1.8 MHz)

01

80 meters (3.5 MHz)

02

60 meters (5 MHz)

03

40 meters (7 MHz)

04

30 meters (10.1 MHz)

05

20 meters (14 MHz)

06

17 meters (18.068 MHz)

07

15 meters (21 MHz)

08

12 meters (24.89 MHz)

09

10 meters (28 MHz)

10

6 meters (50 MHz)

Nimewo antèn
The KPA1500 has antenna connectors ANT1 and ANT2. Some commands use antenna number 0 to mean “both antenna connectors”, or “the other antenna connector”, or “the most recently used antenna connector”.
Using KPA1500 Utility to Test Commands
The KPA1500 Utility Command Tester tab can be used to try individual commands. Try typing ^RV; in the input area. The command and its response are shown on the output area.
Using PuTTY
Other terminal emulators may also be used. PuTTY (from www.putty.org) is sometimes used in development.
Reveye
When the KPA1500 is plugged in, and the power supply rear-panel switch is on, the KPA1500 may appear to be “on” or “off”. When “off”, the main power supplies are switched off, but one small unswitched supply remains on. The microcontroller stays in a low power “sleep” state, responsive to the power button, a REMOTE back panel voltage, an ACC connector pull-down, and arrival of characters on the Host PC USB connector. The main power supply may be turned on by sending ^ON1; via the USB Host. When the amplifier is “off”, the USB connection may not respond to a few characters while waking, so precede ^ON1; with a few semicolons until the KPA1500 responds.

If menu item NET WAKE on LAN is enabled, the KPA1500 may also be awakened by sending a “magic packet”, described in Wake-on-LAN – Wikipedia.

8

Kòmandman ak repons

; Null
GET format: ; (a single semicolon) RESPONSE format: ; (a single semicolon) The KPA1500 Utility sends a few semicolons to determine the KPA1500 serial speed during a connection sequence and to wake up a sleeping KPA1500.
^AA ATU Mode Switch
GET format: ^AA; SET/RESPONSE format: ^AA0; for “global”, ^AA1; for “per band, per antenna”. As you change antennas and bands, ATU MODE can remain the same for all bands and all antennas (“global”), or ATU MODE can be independently set for each combination of band and antenna (“perband, per-antenna”). Some owners may prefer the KPA1500 ATU bypassed when using a separately tuned antenna (such as SteppIR) on some bands. The ATU should be inline on other bands and antenna connectors. Other owners would prefer that the ATU not change between BYP and IN as bands and antennas are changed. ATU Mode Switch can be changed with the ATU MODE SWITCH menu item.
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^AB ATU Settings Per Bin (current band) (new in 01.52, modified in 02.66, 3.00)
GET format: ^AB; SET/RESPONSE format: ^ABnn; where nn is the number of ATU settings per bin. nn is between 1 and 32.
ATU Settings Per Bin determines how many ATU settings may be stored for each antenna for each frequency segment (bin) and should be related to the number of antennas in use on a given band. There is storage enough for 32 distinct ATU settings (shared by all antenna numbers), but you may want fewer settings retained to avoid searching “stale” ATU settings, or to allocate the space across several antenna numbers. In firmware version 02.66 the settings per bin is “per antenna”, so ^AB4; is reserves room for 4 ATU settings on ANT 1 and 4 additional ATU settings for ANT 2.
The number of ATU settings available in each bin was changed from 31 to 32 in version 3.00.
^AB ATU Settings Per Bin (specified band) (new in 01.52, modified in 02.66, 3.00)
GET format: ^ABbb; where bb is the band number (see ^BN). SET/RESPONSE format: ^ABbbnnn; where bb is the band number, and nnn is the number of ATU settings per antenna in each bin for that band, a value between 001 and 032. Leading zeros are required.
^AB ATU Settings Per Bin (all bands) (new in 01.52, modified in 3.00)
GET format: ^ABAB; SET/RESPONSE format: ^ABAB 04 31 31 31 02 31 31 31 32 02 01;
Each of 11 bands (160 through 6 meters) has an ATU settings per bin value, between 1 and 32. Leading zeros are not required.
^AD Attenuator Reason
GET format: ^AD; RESPONSE format (e.g.): ^AD PA CURRENT;
The KPA1500 inserts an input attenuator in response to transient overload conditions. The ^AD response shows the reason the attenuator was most recently deployed. The response is ^AD NONE; if the attenuator has not been deployed since the amplifier was last turned on.
This reason may be viewed on the ATTENUATE REASON LCD status page.
Use ^AS to determine the overdrive attenuator’s current state or ^OC command that returns the current overdrive code.
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^AE Antenna Enable (current band) (extended in version 3.00)
KPA1500 firmware version 3.0 introduces additional antenna numbers for use by stations with several antennas selected by an external switch. ATU settings are stored by antenna number 01 through 32. The external switch informs the KPA1500 which antenna is currently in use, by sending an ^AN command, or the antenna number may be advanced using the KPA1500 front panel ANTENNA switch. KPA1500 firmware stores and retrieves ATU settings for just the selected antenna number.
Antenna enable settings are “per band”. For example, antenna number 15 may be disabled on 20 meters, enabled through connector ANT 1 on 15 meters, and enabled through connector ANT 2 on 10 meters.
To avoid disrupting existing software, ^AE has been extended, but the older forms are unchanged.
GET format: ^AE; SET/RESPONSE format: ^AE0; (both ANT 1 and ANT 2), ^AE1; (ANT 1) or ^AE2; (ANT 2).
Antenna numbers 03 through 32 are not shown or changed with this form of ^AE. Antenna numbers 01 and 02 may also be changed with the ANTENNA ENABLE menu item.
^AE Antenna Enable (specified band)
GET format: ^AEbb; where bb is the band number (see ^BN). SET/RESPONSE format: ^AEbb0; ^AEbb1; or ^AEbb2;
You may wish to use just one antenna connector for some bands and have both antenna connectors available for other bands. Antenna Enable chooses which antenna connector(s) are available by band.
Examples: Enable both ANT 1 and ANT 2 on 20 meters: ^AE050; Enable ANT 1 and disable ANT 2 for 15 meters: ^AE071;
Antenna numbers 03 through 32 are not shown or changed with this form of ^AE. Antenna numbers 1 and 2 can also be changed with the ANTENNA ENABLE menu item.
^AE Antenna Enable (all bands)
GET format: ^AEAB; AB is “All Bands” SET/RESPONSE format: ^AEAB01201201201; Eleven digits, for 160 through 6 meters. Each digit is 0 (for both ANT 1 and ANT 2), 1 thru 2. Antenna numbers 3 through 32 are not shown or changed vis this form of ^AE.
^AE Antenna Enable (new in version 3.00)
GET format: ^AEbbaa; where bb is the band number (see ^BN) and aa is the antenna number, 01 through 32.
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SET/RESPONSE format: ^AEbbaac; where bb is the band number (see ^BN), aa is the antenna number 01 through 32, and c is the “connector number, D for “disabled”, or 1 for “enabled through connector ANT 1”, or 2 for “enabled through connector ANT 2”. For example, ^AE0503; gets the enable state of antenna 03 for 20 meters (bb 05). The response might be ^AE0503D; for “disabled”, ^AE05031; for “enabled through connector ANT 1” or ^AE05032; for “enabled through connector ANT 2”.
In order to maintain compatibility with existing programs using ^AE, Antenna number 1, if enabled, must be routed through connector ANT 1. Antenna number 2, if enabled, must be routed through connector ANT 2. At least one of antenna number 1 and 2 must be enabled on each band. Antenna numbers 03 through 32 may be disabled, enabled through connector ANT 1, or enabled through connector ANT 2.
Thus, ^AEbb012; and ^AEbb021; are ignored, and ^AEbb01D; is ignored if ANT 2 is already disabled on band bb.
^AE Antenna Enable (all antennas for one band, new in version 3.00)
GET format: ^AEbbALL; where bb is the band number (see ^BN). SET/RESPONSE format: ^AEbbALL12DDDDD1111122222DDDDD1111122222; where ^AEbbALL is followed by 32 characters, representing the enable state of antenna numbers 1 through 32. Each character is D for “disabled”, 1 for “enabled through connector ANT 1”, or 2 for “enabled through connector ANT 2”. In the example shown, antenna number 1 is enabled through ANT 1, antenna number 2 is enabled through connector ANT 2, antenna numbers 3-7 are disabled, antenna numbers 812 are enabled through antenna connector ANT 1, antenna numbers 13-17 are enabled through antenna connector 2, etc.
^AE Antenna Enable initialize (new in version 3.00)
SET format: ^AEbbINIT; or ^AEABINIT; for all bands. Resets the antenna enable state for band bb. This enables antennas 1 and 2 and disables antenna numbers 3 through 32 on the selected band bb (or all bands if bb is AB).
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^AI ATU Inline
GET format: ^AI; SET/RESPONSE format: ^AI1; if ATU is currently inline, ^AT0; if ATU is currently bypassed. Gets/changes the ATU bypass relays, without changing the ATU mode. Sometimes the ATU mode is Inline, but the current ATU setting is “bypassed”. This happens when you perform a search tune and the SWR of the antenna without the ATU is sufficiently low (see ^STS, the SWR stop threshold). When the ATU is both “enabled” (inline) and the current ATU setting is “bypassed”, both ATU LEDs are illuminated.
^AL Automatic Level Control Threshold (current band)
GET format: ^AL; SET/RESPONSE format: ^ALnnn; where nnn is the threshold value 000 through 255. This setting can be changed with the ALC THRESHOLD menu item.
^AL Automatic Level Control Threshold (specified band)
GET format: ^ALbb; where bb is the band number (see ^BN). SET/RESPONSE: ^ALbbnnn; where nnn is the threshold value 000 through 255. This setting can be changed with the ALC THRESHOLD menu item
^AL Automatic Level Control Threshold (all bands)
GET format: ^ALAB; SET/RESPONSE format: ^ALAB 000 010 020 030 040 050 060 070 080 090 100; Eleven 1- to 3-digit ALC thresholds, between 0 and 255, for bands 160-6 meters. SET does not require leading zeros.
13

^AM ATU Mode (current band and current antenna)
GET format: ^AM; SET/RESPONSE format: ^AMI; or ^AMB; (“Inline” or “Bypassed”)
Selects the ATU MODE, either “Inline” or “Bypassed”. ^AM interacts with the ATU Mode Switch (“global” or “per band, per antenna”), see the ^AA command. When ATU Mode Switch is “global”, ATU MODE changes by ^AM are “global”. This setting can be changed by holding the ATU MODE button on the KPA1500 front panel.
^AM ATU Mode (specified band and antenna)
GET format: ^AMbba; where bb is a band number, and a is the antenna number: 1, 2, or 0 for both 1 and 2. SET/RESPONSE format: ^AMbbaI; or ^AMbbaB; (“Inline” or “Bypassed”)
Selects the ATU mode: “Inline” or “Bypassed”. ^AM interacts with the ATU Mode Switch (“global” or “per band, per antenna”), see the ^AA command. When ATU Mode Switch is “global”, ATU MODE changes by ^AM are “global”. This setting can be changed by holding the ATU MODE button on the KPA1500 front panel.
^AM ATU Mode (all bands, specified antenna)
GET format: ^AMABa; where a is the antenna number: 1 or 2. SET/RESPONSE format: ^AMABaBBBBIIIIBBBBIII; where “I” is “inline” and “B” is “Bypassed”. There are eleven I or B, for 160 thru 6 meters.
^AM ATU Mode (specified band and antenna, extended in version 3.00)
GET format: ^AMbbaa; where aa is the antenna number, 01 through 32. SET/RESPONSE format: ^AMbbaam; where bb is the band number, aa is the antenna number 01 through 32, and m is I for Inline or B for Bypassed.
^AM ATU Mode (all bands, specified antenna, extended in version 3.00)
GET format: ^AMABaa; where aa is the antenna number 01 through 32. SET/RESPONSE format: ^AMABaaBBBBIIIIBBBBIII; where “I” is “inline” and “B” is “Bypassed”. There are eleven I or B, for 160 through 6 meters.
14

^AN Antenna Select (extended in version 3.00)
GET format: ^AN; SET/RESPONSE format: ^ANa; where a is the antenna number 1 through 9 or ^ANaa; for antenna numbers 10-32. ^AN01; through ^AN32; are accepted as setters. ^AN0; ^AN00; or ^AN+; changes to the next enabled antenna on the current band. This setting can be changed by tapping the KPA1500 front panel ANTENNA button. ^AN; does not switch to a disabled antenna (see ^AE above).
15

^AP Antenna Preferred (current band) (extended in version 3.00)
GET format: ^AP; SET/RESPONSE format: ^APa; where a is antenna number: 0, 1 or 2. The response will be ^APaa; if antenna number is between 10 and 32. ^APbb; is a getter for band bb, not a setter for antenna bb.
Some stations have usable antennas on several antenna numbers. This setting indicates which of these antenna numbers to choose when switching to a new band. Antenna number 0 indicates “last used”, the antenna in use when the KPA1500 last left this band. This setting can be changed with the ANTENNA PREFER menu item.
^AP Antenna Preferred (specified band) (extended in version 3.00)
GET format: ^APbb; where bb is the Band Number. SET/RESPONSE format: ^APbba; where a is antenna number: 0 to 9, or (in version 3.00) ^APbbaa; where aa is the antenna number 00 through 32.
Some stations have usable antennas on different antenna numbers. This setting indicates which of these antenna numbers to choose when switching to a new band. Antenna number 0 indicates “last used”, the antenna in use when the KPA1500 last left this band. This setting can be changed with the ANTENNA PREFER menu item.
^AP Antenna Preferred (all bands)
GET format: ^APAB; AB is “All Bands” SET/RESPONSE format: ^APAB01201201201; 11 digits for bands 160 to 6 meters. This form returns 0 instead of the preferred antenna 10 through 32 on any of the 11 bands.
^AR Attenuator Release Time
GET format: ^AR; SET/RESPONSE format: ^ARnnnn; where nnnn is the release delay in milliseconds, 1400 to 5000.
The overdrive attenuator is released a brief period after the overdrive condition is removed. This setting adjusts that brief period. This setting can be changed with the ATTEN RELEASE menu item.
^AS Attenuator Status
GET format: ^AS; RESPONSE format: ^AShh; where hh are two hex digits representing the reason the overdrive attenuator is deployed. ^AS is a synonym for ^OC, see the ^OC command for details.
16

^BC Band Change Standby
GET format: ^BC; SET/RESPONSE format: ^BC0; to indicate no Mode change on band change, or ^BC1; to switch to STBY on band change.

This setting can be changed with the BANDCHANGE->STBY menu item.

^BN Band Number
GET format: ^BN; SET/RESPONSE format: ^BNbb; where bb is a value from the table below.
KPA1500 band numbers are the same as K3, K3S, KX2, KX3, and K4 band numbers.

bb

Non bann

00

160 meters (1.8 MHz)

01

80 meters (3.5 MHz)

02

60 meters (5 MHz)

03

40 meters (7 MHz)

04

30 meters (10.1 MHz)

05

20 meters (14 MHz)

06

17 meters (18.068 MHz)

07

15 meters (21 MHz)

08

12 meters (24.89 MHz)

09

10 meters (28 MHz)

10

6 meters (50 MHz)

Bands may be changed by pressing one of the KPA1500 front panel BAND buttons.

17

^BP Button Press
SET format: ^BPTnn; for tap, ^BPHnn; for hold.

Simulates a KPA1500 front panel button press. nn is a button identifier from the table below:

Button ID 03 11
19 02 07 20 15 23 06 14 22 05 13 21 04 12 10
18
01
09
24

Button label Status Tap: MENU Hold: EDIT UP arrow to right of LCD DOWN arrow to right of LCD Band 1.8 (160 meters) AUX Band 3.5 (80 meters) Band 5 (60 meters) Band 7 (40 meters) Band 10 (30 meters) Band 14 (20 meters) Band 18 (17 meters) Band 21 (15 meters) Band 24 (12 meters) Band 28 (10 meters) Band 50 (6 meters) Tap: RESET Hold: INFO Tap: MODE Hold: PF1 Tap: ANTENNA Hold: PF2 Tap: ATU TUNE Hold: ATU MODE ON (use ^ON to turn amp on and off)

18

^BRP USB Serial Speed
GET format: ^BRP; SET/RESPONSE format: ^BRPn; where n is a value from the table below:

n

kilobit pou chak dezyèm

0

4.8

1

9.6

2

19.2

3

38.4

4

57.6

5

115.2

6

230.4

The KPA1500 rear panel USB connector, intended for connection to a “host” computer, incorporates an FTDI USB-to-serial adapter that appears to application programs as a serial port.

^BRX Transceiver Serial Speed
GET format: ^BRX; SET/RESPONSE format: ^BRXn; where n is one of the values from the table above for ^BRP.
The rear panel 3.5mm TRS jack, labeled XCVR SERIAL, may be used, with a crossover cable, as a serial connection to an Elecraft K2, KX2, or KX3, Kenwood or some Yaesu transceivers that respond to polling with IF;FA;FB; or as a receive only “sniffer” on the responses from an exciter to a polling computer program, or as a CI-V connection to an Icom exciter (the ^XI command).

^BT Banner Text
GET format: ^BT; SET/RESPONSE format: ^BTxxx…xxx; where xxx…xxx is 0 to 33 characters, 0 to 16 characters for the first line, a new line sequence, and 0 to 16 characters for the second line.
The “Banner” is shown at initial power on and is one of the STATUS pages. It may be used to show a personalized display, i.e. ^BTElecraft KPA1500nK6KR Whidbey; or ^BT ELECRAFTn KPA1500;

“New line” may be entered as an ASCII NL character, or the character backslash followed by the character n, as shown above.

19

^BV Boot Block Version (new in 02.28)
GET format: ^BV; RESPONSE format: ^BV01.07; the version of the “permanent boot block” firmware, which orchestrates firmware installation. The boot block version may also be viewed with the BOOT BLOCK VERSION menu item.
20

^CC Date and Time
GET format: ^CC; SET/RESPONSE format: ^CCYY-MM-DDThh:mm:ss;
The KPA1500 includes a real-time clock/calendar with backup battery intended to provide time stamps for fault log entries. You may set this clock with ^CC. Use exactly two digits for year, month, day, hours, minutes and seconds, and provide hyphens, uppercase T, and colons exactly as shown. The input format is rigid. Example: ^CC17-07-31T13:15:00; for July 31, 2017 at 1:15 PM. The KPA1500 Utility Configuration tab uses this command to set the KPA1500 clock from the Host PC’s date & time. Factory setup uses UTC time.
^CF Write Pending Updates to EEPROM
SET format: ^CF;
Changes to configuration and calibration and current state are written to EEPROM about once a minute, after band change, and during controlled shutdown. ^CF; causes any pending updates to be written to EEPROM within a few tens of milliseconds, and then won’t write them again for about another minute. ^CF; is used prior to configuration save to read the most recent configuration, and during configuration restore to avoid overwriting restored configuration before the post-restore power cycle.
^CO Clock Offset
GET format: ^CO; SET/RESPONSE format: ^CC-64; to ^CC 63; for PCF8523, ^CC-128; to ^CC 127; for MCP7941
Real Time Clock/Calendar (RTCC) parts can sometimes drift slightly, but incorporate a mechanism to trim with an “offset” or “oscillator trim” register.
Refer to section 8.78 of the NXP PCF8523 data sheet (https://www.nxp.com/docs/en/datasheet/PCF8523.pdf) for details on how this may be used. ^CO sets the “Offset register”. MODE 0 is used.
Refer to section 5.6 of the Microchip MCP79411 data sheet https://ww1.microchip.com/downloads/en/DeviceDoc/20002266H.pdf for details on how this may be used. ^CO sets the OSCTRIM register. CRSTRIM (coarse trim) is off.
^RT; may be used to determine which RTCC is installed in your KPA1500.
The intended purpose of the RTCC is fault log entry time stamps; a bit of clock drift isn’t critical.
21

^CP TCP Command Server Port Number
GET format; ^CP; SET/RESPONSE format: ^CP nnnn; where nnnn is a TCP/IP port number.
The KPA1500 provides a TCP command server for this command set. ^CP allows you to change the TCP/IP port number from its default of 1500. Recycle KPA1500 power after changing this address. The UDP and TCP command servers use the same port number.

^CR ATU Capacitors
GET format: ^CR; SET/RESPONSE format: ^CRhh; where hh is a pair of hexadecimal digits indicating the selected capacitors. See http://en.wikipedia.org/wiki/Hexadecimal for a description of this notation.

Examples: ^CR00; selects no capacitors. ^CRFF; selects all capacitors ^CR80; selects only the largest capacitor (1360 pF) ^CRC1; selects the largest, second largest, and smallest capacitors. (1360 + 680 + 8.2 pF)

Hex digit 80 40 20 10 08 04 02 01

ATU relay number K16 K15 K14 K13 K12 K11 K10 K9

Capacitance in picoFarads 1360 680 330 180 82 39 22 8.2

ATU capacitors may also be changed with the ATU CAP menu item.

22

^DA Display Current ATU Setting (new in 02.33)
GET format: ^DA; RESP format: ^DA18086 AN1 Side ANT 340 nH (L06) 0 pf (C00) SWR Bypass 3.0;
Shows the current ATU setting. See ^DF for a description of the output format.

^DF Display Stored ATU Settings

GET format: ^DFfffff; where fffff is a frequency in kHz. Leading zeros may be omitted, e.g., ^DF 14010;

SET/RESP format:

^DF14000-14019 AN1 Side TX 480 nH (L08) 180 pF (C10) SWR Bypass 1.8 AN2 BYPASS

AN1 Side TX 340 nH (L06) 39 pF (C04) SWR Bypass 1.8

ATU settings are grouped into “bins” or “band segments”. Each “bin”, with up to 32 ATU settings, covers 20 kHz on the 20-meter band.
Bin width is 10 kHz on 160 and 80 meters, 100 kHz on 10 meters, 200 kHz on 6 meters, and 20 kHz on the remaining bands 60 through 12 meters. Each band starts at a bin boundary; the first 20-meter bin is 14000-14019, and the center frequency for that bin is 14010.

Each ATU setting consists of an antenna number, the position of the ATU’s bypass, side, capacitor and inductor relays, and the Bypass SWR (antenna SWR with ATU bypassed) captured when the ATU setting was first stored.

In the first response, 480 nH of inductance is represented by ATU inductor relay setting x08, and 180 pF of capacitance is represented by ATU capacitor relay setting x10.

Two different antennas were switched (using an external antenna switch) to ANT1: a vertical and a Yagi. ANT2 is connected to a dummy load.

A single antenna may have several ATU settings, stored at different times, perhaps due to antenna impedance changes with weather or direction. These stored ATU settings are the first ATU settings checked in a subsequent “full search” tune. The first stored ATU setting shown is used for “memory recall” tune. The bin is rearranged on each full search or ATU HiSWR retune so that the most recently tuned ATU setting is evaluated first.

23

^DH DHCP Client Enable
GET format: ^DH; SET/RESPONSE format: ^DH0; (disabled) or ^DH1; (enabled).
Enables or disables the TCP/IP DHCP client within your KPA1500. Disable the DHCP client if you wish to provide static IP addresses (^IP, ^GW, ^NM).
Most home internet routers provide a DHCP server, and the KPA1500 DHCP client should normally be enabled to obtain an IP address from that DHCP server. Some routers provide a capability to consistently assign the same IP address to a specific device, which may be preferable to configuring the KPA1500 to a static IP address.
See https://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol for a description of DHCP.
^DM Demonstration Mode
GET format: ^DM; or ^DMO; SET/RESPONSE format: ^DMx; or ^DMOx; where x is 0 for “normal” and 1 for “demo mode”.
AC power and safety considerations make it unwise to operate amplifiers at full power at conventions. Demo mode keeps the KPA1500 power amplifier bypassed and displays full-range LED and LCD power indications that follow the KEY IN line.
Demo mode may be changed with the DEMO MODE menu item.
^DS Display LCD content
GET format: ^DS; RESPONSE format: ^DSFirstLCD Line (new line char) Second LCD line;
Returns the current content of the LCD screen, consisting of 0 to 16 characters for the first line, then an ASCII NL character (x0A), then 0 to 16 characters for the second line, then a semicolon. If the second line is blank, neither the delimiting NL nor the second line are returned.
^DT Display LCD Text (new in 01.53)
SET format: ^DTLine 1 textnLine 2 text;
Displays a text string on the KPA1500 LCD for about a half second. The LCD shows two lines of 16 characters. “New line” may be entered as an ASCII NL character, or the character backslash followed by the character n, as shown above. ^DT is ignored when there is a current FAULT or OVR LCD message.
24

^DW Fan Speed Dwell Time (new in 02.31, maximum changed in 3.08)
GET format: ^DW; SET/RESPONSE format: ^DWnnn; where nnn is the dwell time, between 3 and 100 seconds. Fan speed normally increases and decreases at fixed temperature thresholds. To avoid rapid cycling, fan speed decreases when temperature decreases and enough “dwell” time has elapsed since the last fan speed change. Dwell time may also be set with the FAN SPEED DWELL menu item.
25

^EB Erase ATU Memory (new in 01.68, extended in 3.00)
SET format: ^EB fffff; where fffff is the frequency in kHz.
Erases ATU settings for the specified frequency and currently selected antenna.
^EC Erase Configuration
SET format: ^ECxyzzy; ^ECxyzzy; is used to reset the amplifier to factory-fresh configuration settings. ^ECxyzzy; does not alter the serial number, fault table, wattmeter calibration, or stored ATU settings. ATU memories may be erased with ^EM. Wattmeter calibration may be changed with ^PJ. Consider saving the KPA1500’s configuration, with the KPA1500 Utility Save Configuration function, before using ^ECxyzzy; to erase it. xyzzy is intended to be difficult to enter by mistake, but easy to remember if you’ve wandered the twisty little passages of Crowther & Woods’ Colossal Cave Adventure. https://en.wikipedia.org/wiki/Xyzzy_(computing)
^EM Erase ATU Settings
SET format: ^EMbba; Erase ATU settings for antenna a on band bb. bb may be AB for “all bands”. a is 1 for Ant1, 2 for Ant2, or 0 for both Ant1 and Ant2.
In version 3.00, ^EMbbaa; erases ATU settings for antenna numbers 01 through 32. Consider saving the KPA1500’s configuration, with the KPA1500 Utility Save Configuration function, before erasing ATU settings. This command may take a couple of seconds.
The ATU MEM ERASE menu item may be used to erase ATU settings for the currently selected band and antenna.
26

FA VFO A frequency (on XCVR SERIAL connector)
SET format: FA000fffffxxx; where fffff is the VFO A frequency in kHz. xxx may be any digits.
FA, followed by an 11-digit frequency in Hz, is the response expected from an Elecraft K2, K3, KX2, KX3, or Kenwood radio when polled with FA;
If RADIO TYPE is Serial and RADIO POLL is on (see ^XI), the KPA1500 sends a string like IF;FT;FA;FB; to the attached transceiver about once a second. Responses contain frequency information used to select ATU settings. If the transceiver is in “auto info” mode, it may not be necessary to poll the radio, as the radio will send IF, FA and FB messages as the transceiver is changed. Alternatively, if a logging program is polling the radio, and a receive-only “Y” arrangement is fashioned so that the KPA1500 can observe the transceiver’s responses, the KPA1500 can adjust ATU settings as the radio frequency is changed. This receive-only “Y” should not connect the TX line of the KPA1500 XCVR SERIAL connector as this would interfere with the logging program’s TX.
FB VFO B frequency (on XCVR SERIAL connector)
SET format: FB000fffffxxx; where fffffxxx is the VFO B frequency in Hz.
See FA above. FA and FB are both helpful, as the KPA1500 needs to choose an ATU setting for the transmit VFO.
^FC Fan Minimum Speed (updated in 02.62)
GET format: ^FC; SET/RESPONSE format: ^FCn; where n is 0 through 5, or +, or -, or /.
The KPA1500’s RF deck fan speed is a function of PA heat sink temperature. Normally the fans are off (speed 0), increase speed as temperature rises, and reduce speed as temperature drops. ^FC sets a minimum speed from 0 (off) to 5 (all fans on at highest speed). Minimum fan speed may be adjusted with the FAN SPEED menu item. ^FS returns the current fan speed, which may be greater than the ^FC minimum because of temperature. New in firmware version 2.62: ^FC+; increases the fan minimum speed by one. ^FC-; decreases the fan minimum speed by one. ^FC/; changes the fan minimum speed to the value prior to the last change. This may be used to “toggle” between two fan minimum speeds.
27

^FE Cancel Full-Search Tune
SET format: ^FE; Once a full-search tune has been started (with ^FT or by tapping the front panel ATU TUNE button), the tune needs continuous exciter RF power to complete searching for the best ATU tuning solution. ^FE cancels an in-progress tune. ^TP may be used to determine if a full-search tune is in progress. A full search tune may also be cancelled by tapping the ATU TUNE button on the KPA1500 front panel.
28

^FL Fault Code
GET format: ^FL; RESPONSE format: ^FLhh; where hh are two hex digits representing the current fault. SET format: ^FLC; to clear current fault. Temperature faults are cleared by temperature change. Faults cause the KPA1500 to switch to Mode STBY. ^FLC; does not change Mode. Faults are also cleared by switching the amplifier to Mode OPER.

Fault code hh 00 10 20 40 60 61 70 80 81 82 83 84 85 90 91
92
B0
C0 C1
F0

Fault description No fault condition Watchdog Timer reset PA Current is too high Temperature is too high. Reset by temperature reduction. Input power is too high Gain (ratio of output to input power) is too low Invalid frequency, > 100 kHz outside ham band or 26-28 MHz 50V supply voltage is too low or too high 5V supply voltage is too low or too high 10V supply voltage is too low or too high 12V supply voltage is too low or too high -12V supply voltage is too low or too high 5V or 400V LPF board supply voltages are not detected Reflected power is too high SWR is very high. This is a quick check for “antenna not connected”, about 18:1 SWR. ATU search tune was unable to find an ATU setting whose SWR is less than the ATU NO MATCH SWR Dissipated power is too high. Dissipated power is PA Current * the 50V supply voltage less the measured RF output power. Forward power is too high Forward power is too high for the current ATU setting. The ATU can match some antennas whose SWR is quite high, but RF power must be limited with these settings, as some power is dissipated as heat in ATU components. This forward power limit is determined by evaluating the SWR of the antenna with the ATU in bypass, called “SWR Bypass”. The “SWR Bypass” LCD status page shows the power limit for the current SWR Bypass. ^TB may be used to compute the power limit for an arbitrary SWR. Gain (ratio of output to input power) is too high

The ^SF command shows detailed information about the current and prior faults.

29

^FQ Transmit Frequency Counter
GET format: ^FQ; RESPONSE format: ^FQfffff; where fffff is the most recent TX frequency count in kHz.
^FQ; may return ^FQ00000; at power on or after a band switch until a transmission occurs. The Transmit frequency count may be observed on the XCVR FREQ and TX COUNT status page. The TX frequency counter is in increments of 8 kHz.
^FR Frequency
GET format: ^FR; RESPONSE/SET format: ^FRfffff; where fffff is the most recent frequency in kHz.
^FR is intended for programs that provide frequency tracking to select ATU memories without requiring transmit. Frequency tracking using the K3 AUXBUS, Icom CI-V, or Kenwood Auto Info use this technique to inform the KPA1500 of the current TX VFO frequency.
Frequency changes made with ^FR cause ATU recall tune if the VFO has moved “significantly”.
The most recent frequency supplied to the amplifier by a transceiver or program is shown in the XCVR FREQ and TX COUNT status page.
^FS Fan Speed (new in 01.47)
GET format: ^FS; RESPONSE format: ^FSn; where n is 0 through 5.
Shows the current fan speed, which is also shown on the FAN SPEED menu item.
FT Transmit VFO (on XCVR SERIAL connector)
SET format: FT0; (VFO A) or FT1; (VFO B) Specifies the transceiver transmit VFO. This information may sometimes be gleaned from the IF response for some transceiver types, but some transceivers do not provide the transmit VFO in the IF message.
^FT Start Tune
SET/RESPONSE format: ^FT;
Starts a full-search tune. When the tune completes or is cancelled, the KPA1500 responds with ^FT; Full search tune may also be started by tapping the KPA1500 front panel ATU TUNE button.
30

^GW Network Gateway Address
GET format: ^GW; SET/RESPONSE format: ^GW 192.168.1.1; The IP address of the router. This address is usually provided by a DHCP server when the KPA1500 connects to a TCP/IP network. See https://en.wikipedia.org/wiki/Default_gateway. The response is variable length; leading zeros are removed from each octet. The Gateway Address may be viewed with the NET GATEWAY menu item. The ^GW; setter (for static IP) requires that DHCP client be disabled with ^DH0;
31

^HS ATU HiSwr Retune (current band)
GET format: ^HS; SET/RESPONSE format: ^HS0; (disabled) or ^HS1; (enabled) ATU HiSwr retune causes the ATU to evaluate up to 16 previously stored ATU settings if SWR rises over the SWR Retune threshold (see ^STA below). This tune requires continuous RF power from the exciter to complete the ATU tuning cycle. This not a “full search” tune. Only ATU settings that have been previously found with a full search tune on or near the current frequency are considered. If a suitable ATU setting is not found, the setting with the lowest SWR is used. A “full search” tune is accomplished by pressing the ATU TUNE button or the ^FT command. “Memory recall” tunes are performed when the radio changes bands or frequencies, and the most recently stored tuning solution for the new frequency is used. Memory recall tunes do not require exciter power. ATU HiSWR Retune may be enabled or disabled with the ATU HiSWR RETUNE menu item. ATU HiSwr Retune was changed to per-band in firmware version 01.26.
^HS ATU HiSwr Retune (specified band)
GET format: ^HSbb; where bb is the Band Number. SET/RESPONSE format: ^HSbb0; (disabled) or ^HSbb1; (enabled).
^HS ATU HiSwr Retune (all bands)
GET format: ^HSAB; AB is “All Bands” SET/RESPONSE format: ^HSAB01001101001; 11 digits (0 or 1) for bands 160 to 6 meters.
32

^I Identify
GET format: ^I; RESPONSE format: ^KPA1500; or ^kpa1500; Identify is used by the KPA1500 Utility to verify that it is connecting to a KPA1500, and to determine if the KPA1500 is running in its application program (UPPER case response) or its permanent boot block (lower case response). ^I; does not require that the main power supply be on.
IF Transceiver Info (on XCVR SERIAL connector)
SET format: IFfffffffffff*****+yyyyrx*00tmvspb01*; KPA1500 uses the response to an IF query to determine the transmit VFO (split indication) and XIT offset to select the ATU setting for the transmit frequency. Consult the Elecraft K2, K3, KX3, Kenwood, Flex, or Yaesu programming references for the detailed format of this message.
^IP Network IP Address
GET format: ^IP; SET/RESPONSE format: ^IP 192.168.1.207; The network IP address normally assigned to the KPA1500 by a DHCP server. See https://en.wikipedia.org/wiki/IP_address. The response is variable length; leading zeros are removed from each octet. The IP address may be viewed with the NET IP ADDRESS menu item. The ^IP; setter (for static IP) requires that DHCP client be disabled with ^DH0; For static IP, disable the DHCP client with ^DH0; and provide dotted octet IP addresses for the KPA1500’s IP address with ^IP subnet mask with ^NM and Gateway address with ^GW. The KPA1500 Utility Configuration Edit has a Network tab to set ^DH, ^IP, ^GW, ^NM and ^WL.
33

^LB LCD Backlight
GET format: ^LB; SET/RESPONSE format: ^LBnn; where nn is a number from 00 to 50. This corresponds to the LCD BACKLIGHT menu item.
^LC LCD Contrast
GET format: ^LC; SET/RESPONSE format: ^LCnn; where nn is a number from 00 to 50. This corresponds to the LCD CONTRAST menu item.
^LI LED Brightness
GET format: ^LI; SET/RESPONSE format: ^LInn; where nn is a number from 00 to 50. This corresponds to the LED BRIGHTNESS menu item.
34

^LQ Led Query (new in 01.62)
Returns the on/off state of the front panel LEDs, for a remote- control program. GET format: ^LQ; RESPONSE format: ^LQppppppppssssmm; as hex digits in big endian order, where pppppppp is the LED power bar as a bitmap (x7FFFFFFF is all bits on, x00000001 is the 25W LED), ssss is the SWR bar as a bitmap (x03FF is all SWR LEDs on, x0003 is SWR 1.0 and 1.1 LEDs on), mm are the remaining LEDs:
x80 FAULT x40 OVR x20 ANT2 x10 ANT1 x08 ATU IN x04 ATU BYP x02 Mode OPER (show Mode STBY if the x02 bit is off) x01 TX Example responses:
^LQ00000000000018; (idling, Mode STBY, ANT1, ATU IN) ^LQ00000000000016; (idling, Mode OPER, ANT1) ^LQ0001FFFF000327; (transmitting with 17 of the 31 power bar LEDs lit,
SWR 1.0 and 1.1 LEDs, Mode OPER, ANT2, ATU BYP, TX
35

^LR ATU Inductors
GET format: ^LR; SET/RESPONSE format: ^LRhh; where hh is a pair of hexadecimal digits indicating the selected inductors.
See http://en.wikipedia.org/wiki/Hexadecimal for a description of this notation.

Examples: ^LR00; selects no inductors ^LR7F; selects all inductors ^LR40; selects only the largest inductor (4400 nH) ^LR61; selects the largest, second largest, and smallest inductors (4400 + 2100 + 50 nH)

Hex digit 40 20 10 08 04 02 01

ATU relay number K7 K6 K5 K4 K3 K2 K1

Inductance (nanoHenry) 4400 nH (4.4 H) 2100 1000 480 230 110 50

ATU inductors may also be changed with the ATU IND menu item.

^LT LED Test
GET format: ^LT; SET/RESPONSE format: ^LTx; where x is 0 for disable, 1 for enable test, 2 lights all LEDs 3, 4, and 5 light LEDs of a specific color. OPER and STBY use one I/O pin, so only one of these LEDs is on at a time. Power off/on resets LED Test.

36

^MA Net MAC Address
GET format: ^MA; RESPONSE format: ^MA54:10:EC:14:75:22; Displays the media access control (MAC) address, a unique value assigned by the microcontroller manufacturer. See https://en.wikipedia.org/wiki/MAC_address. The MAC address is the network address of your KPA1500. The MAC address may be viewed by the NET MAC menu item and the KPA1500 Utility Configuration Edit Network tab.
^NH TX Inhibit Enable
GET format: ^NI; SET format: ^NIx; where x is 0 (disabled) to ignore the ACC connector INHIBIT line or 1 (enabled) to use the INHIBIT line to keep the KPA1500 amplifier bypassed. This may be changed with the TX INHIBIT menu item.
^NM Net Mask
GET format: ^NM; SET/RESPONSE format: ^NM 255.255.255.0; Shows the Subnet Mask, normally assigned by DHCP, in dotted octet format. See https://en.wikipedia.org/wiki/Subnetwork. This may be viewed with the NET MASK menu item The ^NM; setter (for static IP) requires that DHCP client be disabled with ^DH0;
37

^OC Overdrive Code (new in 01.53)
GET format: ^OC; RESPONSE format: ^OChh; where hh are two hex digits representing the reason that the overdrive attenuator is switched in (and the OVR LED illuminated). ^OC and ^AS are synonyms.

Overdrive codes are a subset of the Fault Codes:

Overdrive code hh 00 20 60 61 80 90 91 B0 C0 C1
F0

Deskripsyon
No overdrive condition (OVR LED is off)
PA current is too high
Input power is too high
Gain (ratio of output to input power) is too low
50V ekipman pou voltage twò ba oswa twò wo
Reflected power is too high SWR is very high. This is a quick check for “antenna not connected”, about 18:1 SWR.
The dissipated power is too high. Dissipated power is PA Current times the 50V supply voltage less the measured RF forward power.
Forward power is too high
Forward power is too high for the current ATU setting. The ATU can match some antennas whose SWR is quite high, but RF power must be limited with these settings, as some power is dissipated as heat in ATU components. This forward power limit is determined by evaluating the SWR of the antenna with the ATU in bypass, called “SWR Bypass”. The “SWR Bypass” LCD status page shows the power limit for the current SWR Bypass. ^TB may be used to compute the power limit for an arbitrary SWR.
Gain (ratio of output to input power) is too high

38

^ON Switch Main Power Supplies Off or On (revised in 03.02 to add ^ON/;)
GET format: ^ON; SET format: ^ON0; (power off) or ^ON1; (power on) or ^ON/; (toggle power) Switches the main power supplies off or on. When the main power supply back panel switch is switched on and the amplifier has AC power, a small power supply provides enough current for a “sleeping” microcontroller. The microcontroller “wakes up” when characters arrive on the USB host port when the microcontroller wakes up, it recognizes ^ON1; and turns on the main power supply.
The main power supplies may also be turned on by the front panel ON switch, or by grounding AUX connector pin 8, or supply +12V on the rear panel REMOTE connector.
^ON GET and SET are available when “sleeping”. ^ON/; is new in version 03.02 and toggles power. If power is currently on, ^ON/; turns power off. If power is currently off, ^ON/; turns power on.
^OP Power On Mode (Operate or Standby)
GET format: ^OP; SET/RESPONSE format: ^OPx; where x is 0 for Standby or 1 for Operate. Selects the KPA1500 “mode” when the amplifier is switched on. This setting may also be changed with the POWER ON MODE menu item.
^OS Operate or Standby Mode
GET format: ^OS; SET/RESPONSE format: ^OSx; where x is 0 for Standby or 1 for Operate. Mode may also be changed by tapping the front panel MODE button.
Starting with firmware version 01.41, transition from STBY to OPER with ^OS1 resets any current fault except the temperature fault, which is reset by cooling.
39

^PB ATU Bin Search (new in 02.02)
SET format: ^PB; Evaluates each of the stored ATU settings for the current antenna and frequency and chooses the setting with lowest SWR. The ATU SWR STOP threshold is not referenced to limit this search. This might be used to evaluate each of several similar settings. Transceiver tune power is required.
^PC PA Current
GET format: ^PC; RESPONSE format: ^PCnnn; where nnn is the power amplifier current in Amperes.
^PD Power Bar Decay (new in 02.02)
GET format: ^PD; SET/RESPONSE format: ^PDnnn; where nnn is the decay time in milliseconds, between 3 and 255, default is 32 milliseconds. Sets the LED power bar decay speed. Corresponds to the LED POWER DECAY menu item.
40

^PF Program Function Keys (new in 01.54)
GET format: ^PF1; or ^PF2; SET/RESPONSE format: ^PF1cmd1,cmd2,cmd3,cmd4; ^PF sets or gets a command “macro” string that may be executed when the front panel PF1 (Mode Hold) or PF2 (Antenna Hold) buttons are pressed. Examples: ^PF1^DT You Pressed PF1; ^PF2^BPT01,^DTANTENNA HOLDnreplaced by tap; ^PF1^BPT12,^DTMode change; If you want PF1 (MODE Hold) to be the same as MODE Tap, and PF2 (ANTENNA Hold) to be the same as ANTENNA Tap, use these program function strings: ^PF1^BPT18; ^PF2^BPT01; Command responses are discarded. Use only SET commands within ^PF command strings. Commands are separated by commas, which are replaced with semicolons when the commands are stored. The sequence of characters `’ followed by `n’ is replaced by an ASCII NL character. ^PF strings may be up to 127 characters. Extra characters are discarded. To avoid recursion and loops, commands ^PF, ^BPH01, and ^BPH18 within program function strings are ignored. The KPA1500 Edit Configuration PF Key tab may be used to read and store these command strings.
41

^PJ Wattmeter Adjustment (current band)
GET format: ^PJ SET/RESPONSE format: ^PJnnn; nnn is a scaling factor, expressed as a percentage between 080 and 120, nominally 100, to adjust the KPA1500 forward power displayed value to match an external wattmeter. This setting may also be changed with the WMTR ADJUST menu item. ^PJ does not change watt-based power fault limits.
^PJ Wattmeter Adjustment (specified band)
GET format: ^PJbb; for band bb; SET/RESPONSE format: ^PJbbnnn; for band bb. nnn is a scaling factor, expressed as a percentage between 080 and 120, nominally 100, to adjust the KPA1500 forward power displayed value to match an external wattmeter. This setting may also be changed with the WMTR ADJUST menu item.
42

^PWD Dissipated Power
GET format: ^PWD; RESPONSE format: ^PWDnnnn; where nnnn is the dissipated power, in watts. Dissipated power is the difference between DC power input (PA current times the measured voltage of the 50V DC supply) and the measured RF forward power. This difference is dissipated as heat.
^PWF Forward Power
GET format: ^PWF; RESPONSE format: ^PWFnnnn; where nnnn is the forward RF output power in watts.
^PWI Input Power
GET format: ^PWI; RESPONSE format: ^PWInnnn; where nnnn is the RF input power in watts. Input power is shown as 0 whenever the amplifier’s PA is bypassed (when in mode STBY, or during ATU tuning).
^PWR Reflected Power
GET format: ^PWR; RESPONSE format: ^PWRnnnn; where nnnn is the reflected RF power, in watts
43

^RT Real-time Clock/Calendar Chip Type (new in 02.57)
GET format: ^RT; RESPONSE format: ^RT PCF8253; for NXP PCF8253, ^RT MCP7941; for Microchip MCP7941.
^RV Firmware Version
GET format: ^RV; RESPONSE format: ^RVnn.nn; For example, ^RV01.23; means firmware version 1.23 is installed. ^RV is available when the power supply is off (before ^ON1;)
^RVM Firmware Version
GET format: ^RVM; RESPONSE format: ^RVMnn.nn; For example, ^RVM01.23; means firmware version 1.23 is installed. ^RVM; is available when the power supply is off (before ^ON1;)
^RX Cancel ^TX (new in 3.07)
SET format: ^RX; RESPONSE: ^RX; Cancels key state if invoked by ^TX. Input (exciter) RF should be removed before sending ^RX; If the KPA1500 is in mode OPER and the rear-panel KEY IN connector is pulled down, the amplifier will remain keyed.
44

^SB SWR Bypass
GET format: ^SB; RESPONSE format: ^SBswr; where swr is the SWR measured when the ATU was last bypassed (this occurs during every full-search tune). This is expressed in tenths, 123 is 12.3:1 SWR.
^SF Show Fault
GET format: ^SF; show information for the most recent fault. GET format: ^SFnnnn; show information for fault index nnnn. RESPONSE format: ^SFnnnn faultCode “faultName” YY-MM-DDThh:mm:ss otherInfo val vv;
The “fault index” nnnn is incremented for each new fault log entry and restarts after it reaches the end (wraparound). faultCode is described in the ^FC command above. faultname is a short text acronym for the fault condition. dateTime is the date and time (see ^CC above) shown as YY-MM-DDThh:mm:ss. otherinfo values are shown if non-zero:
Frequency fffff kHz INPUT power in watts FWD forward, or output power in watts REFL reflected power in watts SWR ADC count. The ADC channel varies with fault code. PA CURR PA current in amperes TEMP temperature in degrees C
val is a fault-specific value: For Fault Code “none”, the number of times the amplifier was switched on without an intervening fault. For Fault Code PA Current, the current in Amperes. ADC is the PA current sensor count. For Fault Code forward, reflected, input or dissipated: the power in watts. ADC is the coupler VFWD, VREV, or VINP ADC count. For Fault Code SWR Bypass, the SWR bypass in tenths. ADC is the coupler VFWD count. For Fault Code power gain ratio (output power / input power) is too low or high. 1500W/47W is a power gain ratio of 31.9. Power gain ratio 32 is very near 15 dB. For Fault Code temperature, the heat sink temperature in degrees C. ADC is the temperature sensor count. For Fault Codes related to supply voltage, vol la meziretage in tenths of a volt. ADC is scaled from the supply voltages ak voltage divizeur.
45

^SI ATU Side
GET format: ^SI; SET/RESPONSE format: ^SIT; or ^SIA; The ATU “side” relay switches the ATU capacitance to the source (TX) or load (ANT) “side” of the inductors. ATU Side may be changed with the ATU SIDE menu item.
^SM Save ATU Setting
SET format: ^SM; save ATU setting at the most recently counted TX frequency. SET format: ^SMfffff; where fffff is a frequency in kHz. Saves current ATU settings into the “bin” for frequency fffff. When transmitting, the counted TX frequency replaces fffff.
^SN Serial Number
GET format: ^SN; RESPONSE format: ^SNnnnnn; the amplifier’s serial number, with leading zeros. Serial number may be viewed with the SERIAL NUMBER menu item. ^SN; is available before the power supplies are switched on with ^ON1;
^SP Alarm Tone
GET format: ^SP; SET/RESPONSE format: ^SP0; (turn off alarm tone) or ^SP1; (turn on alarm tone) Faults are accompanied by a short alarm tone from an internal speaker, if ^SP is enabled.
46

^STA ATU HiSwr Retune Threshold (all bands)
GET format: ^STAAB; SET/RESPONSE format: ^STAAB 018 018 018 018 018 018 018 018 018 017 019; Each of 11 bands (160 thru 6 meters) has an SWR value. Provide a 2- or 3-digit number, between 010 and 999 for SWR 1.0 to 99.9. Input format does not require leading zeros.
^STA ATU HiSwr Retune Threshold (current band)
GET format: ^STA; SET/RESPONSE format: ^STAswr; where swr is a 3-digit SWR value in tenths. 1.8:1 SWR is expressed as 018. An ATU HiSWR retune is started when transmitting, and ATU HiSwr retune is enabled (See ^HS above), and SWR exceeds this threshold. This threshold may be adjusted with the ATU RETUNE SWR menu item.
^STA ATU HiSwr Retune Threshold (specified band)
GET format: ^STAbb; SET/RESPONSE format: ^STAbbswr; where bb is the band number, and swr is a 3-digit SWR value in tenths. 1.8:1 SWR is expressed as 018. A “band number” of AB is interpreted as All Bands, so ^STAAB018 sets the ATU HiSWR Retune Threshold for all bands to 1.8:1. An ATU HiSwr retune is started when transmitting, ATU HiSwr retune is enabled (See ^HS above), and SWR exceeds this threshold. This threshold may be adjusted with the ATU RETUNE SWR menu item.
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^STB SWR Bypass Threshold (current band)
GET format: ^STB; SET/RESPONSE format: ^STBswr; where swr is a 3-digit SWR value in tenths. 1.2:1 SWR is expressed as 012. During full-search tune, the SWR of the antenna is measured with the ATU bypassed. If that SWR is low enough (less than or equal to the SWR Bypass Threshold), the full-search tune is stopped, and “ATU bypassed” is used (and stored for later recall) as the ATU setting for this frequency. This threshold may be adjusted with the SWR BYP THRESH menu item.
^STB SWR Bypass Threshold (specified band)
GET format: ^STBbb; SET/RESPONSE format: ^STBbbswr; where bb is the band number, and swr is a 3-digit SWR value in tenths. 1.2:1 SWR is expressed as 012. A “band number” of AB is interpreted as All Bands, so ^STBAB012 sets the SWR Bypass Threshold for all bands to 1.2:1. During full-search tune, the SWR of the antenna is measured with the ATU bypassed. If that SWR is low enough (less than or equal to the SWR Bypass Threshold), the full-search tune is stopped, and “ATU bypassed” is used (and stored for later recall) as the ATU setting for this frequency. This threshold may be adjusted with the SWR BYP THRESH menu item.
^STB SWR Bypass Threshold (all bands)
GET format: ^STBAB; SET/RESPONSE format: ^STBAB 018 018 018 018 018 018 018 018 018 017 019; Each of 11 bands (160 thru 6 meters) has a 3-digit SWR value in tenths. Provide a 2- or 3-digit number, between 010 and 999 for SWR 1.0 to 99.9. Input format does not require leading zeros.
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^STN SWR No Match Threshold
GET format: ^STN; SET/RESPONSE format: ^STN030;
Highest acceptable SWR after an ATU retune (including full search tune). If the tuned SWR exceeds this threshold, a NO MATCH fault occurs. It may be possible to operate, at reduced power, into a high SWR if the forward power is reduced to avoid reflected power faults. A single SWR No Match threshold value applies to all bands. The “all band” and “current band” forms of ^STN may be used (^STNbb; ^STNAB; etc).
^STS SWR Stop Threshold (current band)
GET format: ^STS; SET/RESPONSE format: ^STSswr; where swr is a 3-digit SWR value in tenths. 1.2:1 SWR is expressed as 012.
During ATU HiSWR retune, several previously stored ATU settings are examined. SWR STOP threshold is used to stop looking when an ATU setting with “good enough” SWR is encountered. This threshold may be adjusted with the SWR STOP THRESH menu item.
^STS SWR Stop Threshold (specified band)
GET format: ^STSbb; SET/RESPONSE format: ^STSbbswr; where bb is the band number, and swr is a 3-digit SWR value in tenths. 1.2:1 SWR is expressed as 012. A “band number” of AB is interpreted as All Bands, so ^STSAB012 sets the SWR Stop Threshold for all bands to 1.2:1.
During ATU HiSWR retune, several previously stored ATU settings may be examined. The SWR STOP threshold is used to stop looking when an ATU setting with “good enough” SWR is encountered. This threshold may be adjusted with the SWR STOP THRESH menu item.
^STB SWR Stop Threshold (all bands)
GET format: ^STSAB; SET/RESPONSE format: ^STSAB 010 011 012 013 012 015 012 017 018 019 012;
Each of 11 bands (160 thru 6 meters) has a 3-digit SWR value in tenths. Provide a 2- or 3-digit number, between 010 and 999 for SWR 1.0 to 99.9. Input format does not require leading zeros.
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^SW Standing Wave Ratio (SWR)
GET format: ^SW; RESPONSE format: ^SWswr; Responds with the most recently computed Standing Wave Ratio (SWR), where swr is expressed in tenths. ^SW123; is 12.3 : 1.
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^TB Show Permitted Power for SWR Bypass
GET format: ^TB; requests the permitted power for the current ATU setting’s SWR Bypass. GET format: ^TBswr; where swr is a SWR bypass value in tenths. ^TB032; requests the permitted forward power with an antenna whose SWR bypass is 3.2:1. RESPONSE format: ^TBswr wwwwW; where wwww is the permitted output power for this SWR. The response to ^TB032; is like ^TB032 1565W; The KPA1500 ATU can match many antennas whose SWR is quite high, but RF power must be limited, as some power is dissipated as heat in ATU components. This forward power limit is determined by evaluating the SWR of the antenna with the ATU in bypass, called “SWR Bypass”. The SWR Bypass LCD status page shows the permitted power for the current ATU setting’s SWR Bypass.
^TD Tech Mode enable
GET format: ^TD; SET/RESPONSE format: ^TDx; where x is 0 for DISABLED and 1 for ENABLED. More status and menu pages are shown when TECH MODE is enabled. This setting may be changed with the TECH MODE menu item
^TM Temperature
GET format: ^TM; RESPONSE format: ^TMxxx; where xxx is the PA heat sink temperature in degrees C.
^TP Tune Poll
GET format: ^TP; RESPONSE format: ^TP0; if the ATU is not currently tuning, ^TP1; if ATU tune is in progress.
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^TQ Query Key status (new in 3.07)
^TQ is used to determine if the KPA1500 is keyed, either by the read-panel KEY IN connector or by the ^TX command. GET format: ^TQ; RESPONSE format: ^TQn; where n is
0 (not keyed) when any ^TX command has expired, and KEY IN is not pulled down. 1 (keyed) when a ^TX command has not expired, and KEY IN is not pulled down. 2 (keyed) when a ^TX command has not expired, and KEY IN is pulled down. 3 (keyed) when a ^TX command has not expired and KEY IN is also pulled down.
^TR T/R Delay
GET format: ^TR; SET/RESPONSE format: ^TRnn; where nn is the number of milliseconds, from 00 to 50, to delay the transition from TX to RX after the KEY IN line is released. This might be useful for exciters that continue to send RF after the KEY IN line is released.
^TV Pulse AH-4 KEY Connector (new in 02.55)
SET format: ^TVnnn; where nnn is the number of milliseconds to pull to ground the AH-4 KEY connector (tip of the 3.5mm TUNE jack on the KPA1500 rear panel). Leading zeros on nnn are not required. The pulse interval may be 1 to 100000 milliseconds. The KPA1500 TUNE jack tip might be connected to a K3 or K4 Power On connector (ACC pin 8), which requires a 200 to 1000 mSec pull-down to turn power on. KPA1500 ATU TUNE also pulls down the AH-4 KEY connector during tune.
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^TX Simulate KEY IN in software (new in 3.07)
SET format: ^TX; or ^TXnn; RESPONSE: ^TX; Simulates pulling the rear panel KEY IN line down with a software command. An optional timeout period, 1 to 99 seconds, may be specified with ^TX1; through ^TX99; When the timeout elapses, ^TX is cancelled. ^TX; without a specified timeout, stays in effect until an ^RX; command is received. Sending ^TX with or without a timeout period replaces any prior ^TX timeout period. ^TX is removed by the ^RX command or when an optional timeout expires, or by pressing the amplifier RESET button, or sending the ^BPT10; command (RESET button tap). The intended use is for external control software to send something like ^TX60; periodically while key down is needed and ^RX; when KEY IN is no longer needed. Should connection to the control software be lost, the amplifier will turn off ^TX when the timeout expires. The ^TX command setting is effectively parallel with the hardware KEY IN line. If the KEY IN line is pulled down, the amplifier is keyed regardless of ^TX or ^RX. ^TQ may be used to determine the ^TX state. The KPA1500 requires approximately 5 milliseconds of ^TX or KEY IN lead time before exciter RF arrives. Exciter RF should be removed before issuing ^RX;
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^VG Display T/R State
GET format: ^VG; RESPONSE format: ^VG TRINHIBIT x01 TR_STATE_RX 3R:1 3T:0 Bias:0 PA STBY KeyIn:0 STANDBY;
This is a diagnostic command.
The ^VG; response shows the T/R state machine’s variables, some amplifier control lines, and reason(s) for keeping the T/R switch in RX. In the examples above, the operating mode is STANDBY. When the PA is key-down with input power, the response is usually ^VG TR inhibit x00 TR_STATE_TX 3R:0 3T:1 Bias:1 PA OPER KeyIn:1;
^VI PA Voltage ak Kouran
GET format: ^VI; RESPONSE format: ^VIvvv iii;
This command is provided for compatibility with KPA500. Returns the current PA main power supply voltage (in tenths of a volt) and PA current in whole Amperes. ^VI513 061; is 51.3V at 61 Amperes.
^VM1 Voltage Monitor (10-volt supply)
GET format: ^VM1; RESPONSE format: ^VM1 09814; for 9.814 volts.
Shows the computed voltage, in millivolts, of the 10V power supply. This is computed from an ADC count and the expected values of a pair of voltage divider resistors, and may not be accurate to 1 millivolt.
^VM2 Voltage Monitor (12-volt supply)
GET format: ^VM2; RESPONSE format: ^VM2 11602; for 11.602 volts.
Shows the computed voltage, in millivolts, of the 12V power supply. This is computed from an ADC count and the expected values of a pair of voltage divider resistors, and may not be accurate to 1 millivolt.
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^VM3 Voltage Monitor (-12 volt supply)
GET format: ^VM3; RESPONSE format: ^VM3 11483; for -11.483 volts.
Shows the computed voltage, in millivolts, of the -12V power supply. This is computed from an ADC count and the expected values of a pair of voltage divider resistors and may not be accurate to 1 millivolt.
^VM5 Voltage Monitor (5-volt supply)
GET format: ^VM5; RESPONSE format: ^VM5 05109; for 5.109 volts.
Shows the computed voltage, in millivolts, of the 5V power supply. This is computed from an ADC count and the expected values of a pair of voltage divider resistors and may not be accurate to 1 millivolt.
^VMH Voltage Monitor (50-volt supply)
GET format: ^VMH; RESPONSE format: ^VMH 52749; for 52.749V.
Shows the computed voltage, in millivolts, of the 50V power supply. This is computed from an ADC count and the expected values of a pair of voltage divider resistors and may not be accurate to 1 millivolt.
^WL Wake on LAN (new in 01.67)
GET format: ^WL; SET/RESPONSE format: ^WL0; (disabled) or ^WL1; (enabled)
Specifies whether the KPA1500 may be “wakened” by receipt of an Ethernet “magic packet” consisting of 6 bytes of 255 followed by 16 repetitions of the KPA1500’s MAC address. See Wake-on-LAN – Wikipedia. Wake on LAN may also be changed with the NET WAKE on LAN menu item.
^WS Forward Power and SWR
GET format: ^WS; RESPONSE format: ^WSwwww swr; where wwww is the Forward Power in watts, and swr is the SWR in tenths. For example, ^WS1204 014; is 1204 watts Forward Power and SWR 1.4:1.
This command is provided for KPA500 compatibility, but the KPA500 uses 3 digits for watts.
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^XH XCVR SERIAL as HOST (new in 01.62)
GET format: ^XH; SET/RESPONSE format: ^XHx; where x is 0 for disabled, 1 for enabled. When enabled, the rear panel XCVR SERIAL connector is repurposed to function as another means of entering commands and responses (from this document), for use perhaps with a UART from a single board computer. When XCVR SERIAL as HOST is enabled, the Icom CI-V and Radio Type Serial frequency advisory functions implied by RADIO TYPE ICOM and RADIO TYPE SERIAL are unavailable (see ^XI for Radio Type) This may be set with the XCVR SERIAL HOST menu item.
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^XI Radio Interface (RADIO TYPE 5 added in version 3.04)
GET format: ^XI; SET/RESPONSE format: ^XInp; where n is a RADIO TYPE number and p is a RADIO POLL value, 0 or 1.

These values may be set with the RADIO TYPE and RADIO POLL menu items.

RADIO TYPE number 0
1 2
3

RADIO TYPE
K3 / K3S. Uses 15-pin ACC cable with BAND0-BAND3, AUXBUS for K3 control and frequency information. Set K3 to KAT500=Y. K3 provides transmit frequency with 8 kHz granularity. BCD (Yaesu BAND0-BAND3) on 15-pin ACC cable Icom: Optional Band and Band Reference voltage on 15-pin ACC connector, AH-4 interface for Icom front panel ATU TUNE, XCVR SERIAL configured as CI-V for operating frequency information (unless ^XH is enabled) Serial: K2, KX2, KX3, Kenwood, Flex, and some Yaesu models using cross-over serial connection. Uses XCVR SERIAL as TTL RS232 for frequency information. KX2, KX3 should use AUTO INFO: RIG CTRL and no RADIO POLL.

RADIO POLL
Pa itilize
Pa itilize Pa itilize
1 to poll for TX frequency (IF;FT;FA;FB;)

When ^XH is enabled, the XCVR SERIAL port is repurposed, and RADIO TYPE SERIAL does not poll for or accept frequency responses.

4

K4. Uses 15-pin ACC cable with BAND0-BAND3, AUXBUS for K4 Not used

control and frequency information. K4 provides transmit

frequency with 1 kHz granularity.

5

TTL. Identical to RADIO TYPE Serial except that the bits are

1 to poll for TX

inverted. Intended for Yaesu FT-710.

frequency (IF;FT;FA;FB;)

This value is new in firmware version 3.04.

When ^XH is enabled, the XCVR SERIAL port is repurposed, and RADIO TYPE TTL does not poll for or accept frequency responses.

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^XK ATU XCVR Key
GET format: ^XK; SET/RESPONSE format: ^XK0; (disable) or ^XK1; (enable) When the KPA1500 needs transceiver TUNE POWER for ATU tuning, it can send an AUXBUS message to a K3 or K3S with MCU 5.63 or later, and the transceiver will provide TUNE POWER (equivalent to holding the K3 TUNE button). This can also be accomplished, for most radios, by connecting the tip of the KPA1500 3.5mm TRS TUNE connector to the transceiver’s straight key input. The tip of the TUNE line is pulled low when the ATU is retuning. A separate keying cable is required. ^XK only affects the K3 AUXBUS message, the TUNE connector tip is always pulled down during ATU TUNE when the ATU needs TUNE POWER. If this function is disabled, press the KPA1500 ATU TUNE button to start a full search tune, then press TUNE on the transceiver to provide a steady signal for ATU TUNING. When ATU TUNE completes, tap TUNE again to stop the transceiver signal.
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Icom “Transmit Frequency” and “Current Frequency”
When the KPA1500 selects RADIO TYPE ICOM (via ^XI or the RADIO TYPE menu item), the XCVR SERIAL port is changed to CI-V, and the KPA1500 may read frequency messages from an Icom transceiver’s CI-V connector via a 3.5mm cable (mono or stereo, only the tip is used).
The Icom transceiver should be in CI-V “transceive” mode, the KPA1500 XCVR SERIAL speed (^BRX or SERIAL SPEED XCVR menu item) must match the transceiver’s CI-V Baud Rate.
The expected format of the Transmit Frequency message (in hex) is:
xFE – START xFE repeated START x?? controller address (ignored) x?? transceiver address (ignored) x1C Command code x03 command sub code (transmit frequency) 5 BCD bytes of operating frequency, in reverse order. xFD END
Pou egzanpample, a CI-V hex message of FE FE 01 94 1C 03 50 25 18 14 00 FD is interpreted as 14,182,550 Hz, rounded to 14183 kHz.
The CI-V Transmit Frequency message is used to select bands and the ATU setting for the specified frequency.
The KPA1500 does not transmit CI-V messages. It accepts operating frequency messages generated by the transceiver as it is tuned.
IC-7300, IC-7600, and IC-7610 send a 1C 03 Transmit Frequency command as the VFO is changed if “transceive” is enabled.
Newer Icom radios send the 1C03 “transmit frequency” and a “current frequency” message as the VFO is tuned. If a 1C03 message is received, the KPA1500 ignores “current frequency” messages. Older Icom radios send only a “current frequency” message, which changes when transmitting in split. The “current frequency” message is accepted if no 1C03 “transmit frequency” messages have been observed since the last KPA1500 power on.
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