[TenTec] Omni D issue

[Mike Hyder -N4NT-]

If it were my rig, here's what I'd do:

1. with drive at minimum, I would turn the rig to tune or key it on CW.

2. then I would watch the current drawn by the rig as I slowly advanced the 
drive control.

3. if there happened a sudden increase in the current, I would shut it down 
immediately.  That would be an indication that the final amplifier (or the 
driver/final combination) was oscillating

Since those rigs will oscillate in the final if they do not receive proper 
ALC voltage AND a self-oscillating final has outputs everywhere, there is no 
way to ever match an antenna.

The diodes that generate the ALC are on the same board as those which 
develop the SWR meter current.  They sometimes fail if the rig is connected 
to an antenna when a lightning storm is within maybe a mile.  If you do see 
a sudden increase in the current, I suggest you just replace all four of 
those diodes and if there is a fifth in close proximity, change it too.

Please advise the group if you are successful in repairing your rig.

73, Mike N4NT

----- Original Message ----- 
From: <tubsc66 at aol.com>
To: <tentec at contesting.com>
Sent: Friday, September 10, 2010 6:43 PM
Subject: [TenTec] Omni D issue


> Hello everyone, my Omni D has developed an issue that puzzles me (not hard 
> to do...:), it has developed a
> high-swr issue that none of my other rigs have (I have other TT's and 
> riceboxes), same antenna, autotuner
> and feedline. The autotuner is unable to find a match unless the output is 
> very low. When releasing the
> mic (PTT),  there is a delay in the receive signal coming back to full 
> strength, it is
> accompanied by a "click", which must be the T/R relay sticking. Could the 
> relay cause such an
> issue? I thought swr issues were dependant on the antenna, not the radio. 
> Anyway, I'd like to
> fix it, any thoughts out there? Thanks!
>
> 73's
>
> Chris  KC5IIE