[TenTec] OMNI VI - Low Power output - Update

[Dennis Ashworth]

More information on the low power condition discussed below:

I suspect the inaccurate SWR reading on the internal meter is causing 
the drive to be reduced to the driver/finals. The drive reduction 
feedback loop is a protective circuit to keep from damaging the finals 
when improper loads are encountered. I'll bet the inaccurate SWR 
readings (3.:1 into a dummy load) are caused by one or both defective 
Schottky diodes in the SWR directional coupler circuit. Does this sound 
reasonable? Has anyone seen this before? Other things to check?

Dennis, K7FL

===

-------- Original Message --------
Subject: 	OMNI VI - Low Power output
Date: 	Sat, 09 Jan 2010 11:20:10 -0800
From: 	Dennis Ashworth <dennis at ashworth.org>
Reply-To: 	dennis at ashworth.org
To: 	TenTec at contesting.com



The power output of my OMNI has dropped to around 30 watts, as measured 
on the OMNI front panel and an external power meter. The collector 
current (as displayed to front panel meter) is about 15 A.  SWR 
indication on the front panel is incorrect, indicating 3:1 into a dummy 
load -(1:1 indicated on the external power meter).

Any ideas?

Tnx
Dennis, K7FL