No mic audio in single K3 configuration

[K0PC]

I have a K3-twin setup operating correctly. I can use SSB with the microphone plugged into the front of the RRC. I also want to be able to operate without the K3 at the control end in a setup as described on page 211 of the Users Manual (Rev A32). When I try this I can't get mic audio to go through to the radio.

Starting with the working K3-twin profile I changed the Program Mode to 4-Yaesu, Kenwood, Elecraft at both RRCs. I also changed the COM2 mode to Mode 4 at both ends. After doing this I can still operate CW and use a logging program to control the radio but my microphone audio doesn't work. I'm using Rev 2.85 software in the RRCs on both ends.

Does anyone know where my mic audio went?

Thanks & 73,
Pat  KØPC

[dj0qn]

There should be no difference between the two methods if you had the microphone plugged into the RRC before and
after. The mode and CAT settings have no effect on microphone audio, this is done in hardware through the red
strappings in the RRC.

The only thing that occurs to me is that your K3 has the microphone input set incorrectly, i.e. back or front of the K3.
I would first look there instead of the RRC for the problem, or in the wiring on the radio side.

73,
Mitch DJ0QN / K7DX

[K0PC]

Thanks for the reply Mitch. I don't change anything in the K3 settings or connections on either end. I simply changed the RRC settings at each end to use Program Mode 4 and the mic audio goes away. Of course I restart both RRCs with the new settings. I can always go back to my Twin K3 setup and everything works.

I'm stumped.

[sm2o]

I agree with Mitch. This is nothing which can be caused by the mode change. Are you sure you have not change the mic input settings in the K3 Back/Front
maybe the PC program you use have some default for that setting

73 de mike

[K0PC]

In order to eliminate any other possible issues I did a factory reset on both controllers (hold reset for 20 sec). In the default configuration (prog mode 14 K3 twin) I can operate in both phone and cw modes as expected. The microphone is plugged into the front of the control RRC.

I changed the program mode on both controllers to 4 - Yaesu, Kenwood, Elecraft and restarted them. Now I use the Connect button on the status page (control K3 not powered up) and I can operate CW but get no microphone audio out on phone.

No external logging software is running, I didn't make any changes to the K3 settings. This is all running on my local network at this point.

[sm2o]

Hi
you do not have to change the radio-RRCs settings. Leave all settings exactly as when you use K3-twin. Then you can alternate between twin and PC control without changing anything. The control unit should be to programmode 4. Again the mode change has nothing to do with the missing mic audio. It must be some settings in the K3 which change Micgain = 0 or some other setting.

73 de mike

[K0PC]

I appreciate the hints that I am changing something on the K3 but I assure you I am not. Both radios are sitting on the desk in front of me and the mic audio works in one configuration and not in the other. I'm not touching the remote K3 at all. In the K3 twin configuration I connect by turning on the control K3 and the mic works. In the mode 4 configuration I am simply using the Connect button on the status page (with the control K3 off) and the mic does not work. In both cases the K3 settings for mic input and mic gain are not touched.

I originally left my radio RRC settings to K3-twin all the time. I only changed it to mode 4 to try to solve this problem. The same problem occurs regardless of whether the radio RRC is set to mode 14 or mode 4.

I am out of ideas on what to do next. Is there anything else I can do to track this down?

[K0PC]

I think I have found the problem. When I change from Program Mode 14 - K3 Twin to Program Mode 4 - Yae/Kwd/Ele the 8 volts supplied to the AUX/MIC connector goes away. Changing back to mode 14 brings it back. I am using an Icom hand mike that needs the 8V to work.

I don't see anything in the Control settings that looks like it would restore the 8V. Is there a safe place on the board to tap 8V and route it to the MIC connector? One of the pins on the 14 pin header on the left side of the board has 8V but I don't want to use it unless it is safe.

73,
Pat KØPC

[sm2o]

If JMP1 is in place 8V are always feed to to the mic element via the mic wire eg "phantom powering" independent of program mode

Rgds mike

[K0PC]

Hi Mike,

I had JMP1 in place all the time. But I still see the loss of 8V in mode 4. When I am in mode 14 I get 8V on the MIC even with JMP1 removed. I can measure 8V on both of the pins of JMP1 (with jumper removed).

When I change to mode 4 the 8 V disappears on the MIC with JMP1 in place. If I remove JMP1 I get 0V on both pins.

As a test I tried the other modes and got 8V on the MIC in modes 5, 8, 9, 14, and 17. All other modes put 0V on the MIC. JMP1 was in place for all modes. I am running ver 2.85 of the firmware.

Can I tap the 8V from the 14-pin header on the left side of the board? I measured 8V on the back-right pin.

73,
Pat KØPC

[sm2o]

You are not talking about the Phantom power to the mic, it's not switched it's always there. Maybe you are talking about 8V in the strap socket, it's switched. Yes you can tap 8V from the WiFi socket if you want. You must use some odd microphone if it needs separate 8V. All I have seen is working with 8V Phantom to the mic element


/mike

[K0PC]

Hi Mike,

Well it was the microphone. I was using an Icom HM-151 mic that came with my IC-7000. It has a lot of functions built into the mic (band buttons, mode & filter buttons, etc). Evidently it needs a hefty 8V supply to operate. I borrowed an Icom HM-95 from a friend and it works fine with the phantom 8V in both mode 4 and mode 14.

I will either route 8V from the wifi connector to the MIC jack or look for a simpler microphone.

Thanks for your help with this.

73,
Pat KØPC