[TenTec] Help: Omni 6 keying problem

[Nat Davis]

My Omni 6 (with opt 3 upgrade) has developed a problem when it is 
keyed.  Any troubleshooting help would be appreciated....

When I key the Omni by holding a key down or pressing the "tune" control, I 
get "normal" power output initially and then the power output starts to 
fluctuate between on and off.  This makes the "tuning up" process a real 
bear.  This occurs regardless of the setting of the RF power output knob on 
the radio.  I can hear a relay opening and closing when the power goes up 
and then down.

Is this problem symptomatic of a failing relay on the low pass filter 
board?  The relay on that board that switches output power to the antenna, 
relay K1 in my manual, is controlled by a voltage "T" that originates on 
another circuit board.  Could this signal be going bad?

Obviously, I have not taken to rig apart to troubleshoot yet.  Looking for 
advice first.

Thanks for your help.

Nat
N4EL