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Shouldn't my amp switch bands as I switch slices?

Newbie here, just got my Flex 6400.
It works great with 2 slices, 2 WSJT-x, 2 JTAlert, and 1 instance of Gridtracker.
The only unexpected behavior is that my amp (KPA500) doesn't switch bands as I switch slices by clicking or double-clicking on a slice. Shouldn't it?
Also, it seems to default to one slice ie on 1 slice it will switch bands as I transmit then switches back to the other slice when on Rx. Shouldn't it stay on the Tx slice?


  • KD0RC
    KD0RC Member, Super Elmer Moderator

    Congratulations on your new rig!

    The KPA 500 will follow the radio. There are two RS-232 ports on the amp, one goes to your PC and the other goes to the Flex 6400. You need a true FTDI USB to serial cable and you need to configure the cable.

    Plug in the cable to the amp, then go to Settings, USB Cables... Select the cable which should have come up in the window, and click the Edit button. Now you can name it and set its type to CAT. Auto-Report should be Enabled.

    Now click the Advanced arrow and set the RS-232 parameters as shown below.

    I'm not sure that I understand the second issue. Do you by any chance have SPLIT selected?

  • rah50
    rah50 Member ✭✭
    Thanks Len, but I guess I didn't explain my issue well. I have the KPA500 integrated properly, it works perfectly with 1 slice.

    The issue is using 2 slices and there are 2 parts to problem:

    1: Should the amp switch bands whenever I switch slices by clicking on a slice?
    2. When transmitting on say Slice A, the amp stays on Slice A for Rx and Tx. When transmitting on Slice B, the amp switches bands to Slice B for Tx, but the switches back to the Slice A for Rx. Shouldn't it stay on B for both Rx and Tx, seems like unnecessary switching and perhaps unsafe?
  • rah50
    rah50 Member ✭✭
    Split is set to Fake It in WSJT, is there another split setting somewhere?
  • KD0RC
    KD0RC Member, Super Elmer Moderator

    Hmmm... I don't see that behavior in mine. I have a 6400 and KPA 500 also. My KPA500 follows the band that has the TX flag turned on. So in this configuration, the amp properly shows 50.0 MHz. I can do whatever I want with the 10 meter slice (except change it ot TX) and the amp won't change.

    As soon as I make the 10 meter slice the TX slice, the amp changes and reports 28.0 MHz.

    Do you have both slices open on the same panadapter? That will cause the issue that you describe. Try opening a second panadapter for the second slice and I think everything will work the way you would expect.

    Start by closing one slice, then click the add panadapter button:

    Now change the band of the second panadapter and see if it behaves more like what you expect.

  • rah50
    rah50 Member ✭✭
    Hi Len:

    **** rookie error on my part: You can only switch slices by clicking the small TX symbol! Now everything works as expected, KPA follows slice as expected.

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