[TenTec] Omni VI Plus problem, help requested?

[John Swartz]

I have an Omni VI Plus that has developed a problem on transmit. Can 
anyone on this list help me, please?

When I power up the transceiver, in CW mode (I only operate CW), it will 
generate 80-90 watts output with the PWR control fully clockwise. After 
several transmissions over a course of barely 10 minutes, power output 
progressively declines and the ALC light dims and goes out.  If I reduce 
the power setting to about 3/4 or less, the ALC light will come back, 
but power output will continue to decline and as it does so, the ALC 
light will continue to dim and extinguish.  This happens on all bands, 
but not at the same rate.  On 160, 80, 12 and 10 meters the decline is 
much more pronounced and rapid, 40, 30, 15 and 17 decline a bit less 
precipitously, and 20 less so.  Even so, after about 15 to 20 minutes of 
intermittent CW, there is very low output on any band and the ALC 
indicator does not light at all.

If I start operating at reduced power, I can rely on the output to 
maintain its level for a greater amount of time, but it does decline 
after a while, but I couldn't count on it for any extended operating 
period of more than, perhaps, 30 or 40 minutes.

Can anyone give me any ideas about what is going on, and how it might be 
fixed?  The receive function is not affected.  I would seriously like to 
keep this rig working if I can.

Thanks for your time and attention, 73, John WA9AQN



-- 
John Swartz
Amateur Radio WA9AQN
15076 New Salem Bluff Road
Petersburg, IL 62675
USA
217-632-5925