[TenTec] Fw: OMNI SIX PLUS problem with carrier on SSB

[Ken Brown]

Hi Bob,

I have an Omni VI, not a Plus version. I'm pretty sure there is very 
little difference in their respective balanced modulators. The manual 
for it does not give a procedure for adjusting R3 and R4. Although it 
does state that these are the pots to adjust  for carrier null. What you 
want is minimum carrier output when in either USB or LSB. There are 
various ways of detecting the carrier. A separate receiver, an 
oscilloscope, etcetera. It should not really matter what kind of filter 
you are using, carrier null is minimum carrier output. If you do have a 
wider filter, or have your BFO frequency set so that it is closer to the 
filter bandpass, then there will be less attenuation of carrier from the 
filter and more residual carrier will get through. Still the adjustment 
is made the same way and you should be able to get the carrier down to 
an acceptable level. Then when you have a really strong signal at a 
fellow ham's station, he will still probably be able to hear some 
residual carrier. You said he heard your carrier at S1, and you did not 
say what signal strength he heard your modulation. My Omni VI book says 
carrier supression is typically 60 dB. If your fellow ham heard your 
modulation at 36 dB over S9, then your rig was meeting that specification.

DE N6KB 

>Re: carrier on SSB signal
>
>Has anyone had any problems with the carrier adjustment on an OMNI SIX PLUS with all the Ten Tec stock audio filters (no INRAD audio filters) installed (all five slots with TT filters).
>
>I was on LSB (40 meters) this morning. I fellow ham broke in to my QSO to tell me that I had a strong carrier on one side of my SSB signal. He said is was around S1 with no audio (I was holding down the mic button with no modulation).
>
>Is there an easy adjustment or fix for this problem? I was told there were null adjustments on the TX audio board, R3 and R4. Any advice and help would be greatly appreciated, thanks.
>
>  
>