[Elecraft] K3/O-Mini + Remote Rig Configuration for Heil Headset

[Barry Baines]

I am having difficulties getting my Heil ProSet with the HC-4/HC-5 mic cartridge to work with the K3/O-Mini + RemoteRig (purchased from Elecraft) where there is no audio reaching the K3 at the radio site.  I’m told that the Heil mic cartridge is a dynamic element with no pre-amp gain.  The mic connection for the K3 is set for the rear panel with no Bias and “Low” Gain per the Heil documentation on their website (“All Things Elecraft”).   The incoming audio (transmit) is fed from the Remote Rig-Remote front panel Aux/Mic using the supplied cable from Elecraft that connects to both the PTT In and Mic-Mono at the back of the K3.  

I’ve tried various configuration setups with the Control-RR to see if changing the audio level from the control site makes a difference, such as increasing the Codec inp gain, changing Codec Inp preamp to “no” and varying the Audio Quality specified at both remote rig units.  Using TX-Test, I then speak into the Mic and check for ALC and compression, varying the mic gain and compression.  At no time do I see any measurement on the K3/O-Mini meters for ALC and compression.  The “monitor” capability is also not working as I can’t hear myself through the headset.  

I’m wondering if the Remote Rig system is setup for the Elecraft MH-2 mic which I understand does have amplification.  If so, this may prevent a dynamic mic cartridge working properly with Remote Rig-Control.  I’ve tried using the mic input on the side of the K3/O-mini as well as using the Kenwood adapter to utilize the 8-pin connector.  I saw a note the other day from Mark, VA2MM which shows his setup for the Radio Side and Control Side;  those settings didn’t work. I’ve tried the default settings specified in the “K3-Remote Owner’s Manual” with no success.

I have excellent audio quality coming from the K3 to the K3/O-Mini unit;  the receiver audio sounds fine at the control site. I presume this means that there is a good audio connection between the two remote rigs. The radio site uses DSL with a low bandwidth (10 Mpbs Down/784 Kpbs Up) so if the receiver audio is good, I’m presuming that bandwidth wouldn’t be the problem on the transmit side as it would be on the higher capacity downlink to the DSL site.  

Any suggestions on what to check either in the K3 configuration or the Remote Rig setup at either the control site or the remote site?  Given that the connection is through the internet, are there any router or other considerations that I should check?  At the Remote (radio) site, I’m using the default UDP/TCP configurations for RRIG_cmd, RRIG_audio, and RRIG_sip with port forwarding to the Remote Rig-Radio.   I do have the ability to access the Remote Rig-Remote from the control site so that I can make configuration changes at both ends and restart both Remote Rig devices. Consequently, I can update both Remote Rig boxes (control and remote) as needed.   

I should also note that the last time I was at the remote site, I was able to test the system at the station itself and  push audio from the K3/O-Mini to the K3 via the Local Area Network when the K3/O-mini was next to the K3 on the same LAN.   When I got back to the “control site” , I had no transmit audio at al to the K3..  That may suggest an internet issue, but at this point I have no real handle on the source of the problem.  

Thanks and Merry Christmas,

Barry Baines, WD4ASW
Westborough, MA (Control Site)
Folkston, GA (Remote Site)