[TenTec] Does this happen to you on transmit...OMNI V ??

[Jim Brown]

On 2/24/2014 2:56 PM, Bob McGraw - K4TAX wrote:
> Initially seems like a RFI issue to me.

Might be. Suggestion #1 gets both to that and the PS voltage issue.

>
> 1. Try it on a known good dummy load with a known good jumper between 
> the radio and the load.
>
> 2. Make sure the DC power connections and connectors, both on the 
> cable and at the radio are solid, clean and tight.

I also smell too much voltage drop in the DC supply.  What is the 
supply? What is the DC cable between PS and rig?  What cable diameter 
and length?

>
> 3. Make sure the power supply voltage is correct at the radio and thus 
> the PS regulator is not falling out of regulation.
>
> If it works on #1 then it is likely the antenna or the associated 
> jumpers connecting various pieces of equipment.

Yes, poor quality coax jumpers can do this.  Anything from crummy coax 
to poorly installed connectors -- even junk connectors.

Back to the "RF in the shack" issue -- the Omni V has Pin One Problems 
at all of the RCA connectors on the rear panel, and may have one at the 
mic connector too.  RF feedback is CAUSED by Pin One Problems. If our  
antenna is working and is close to the shack, we WILL have RF in the 
shack, but it is the job of our gear to reject it. Pin One Problems 
COUPLE RF into our gear. Any cable plugged into a connector with a Pin 
One Problem, including those RCA connectors, becomes an antenna coupling 
our TX RF back into the rig.

Study k9yc.com/RFI-Ham.pdf and the other stuff at k9yc.com/publish.htm 
that talks about Pin One Problems.

73, Jim K9YC