I would first suspect one of the three 1N4007 quasi-PIN diodes in the T/R
circuit. I replaced mine with Microsemi UM-2110 1KV true PIN diodes made
specifically for high power H.F. transmit switching. Main-to-Aux antenna
isolation also dramatically improved for use with low band beverages and
loops. Try connecting your antenna to the AUX antenna port.
From: Clark Savage Turner <email@example.com>
To: firstname.lastname@example.org <email@example.com>
Date: Tuesday, November 10, 1998 10:59 PM
Subject: [TenTec] OMNI VI deafness
>Gads, my OMNI VI luck is down this last few weeks.
>I was fiddling around with a 160 meter antenna and using a
>tuner ... and there was clearly some RF flowing back around
>the shack. The rig (power supply) shut down pretty quickly
>when I pushed the power up at all.
>I did this twice, now the receiver is deaf. It can
>hear the rig next to it tuning up (barely) but nearly
>completely deaf to the band with an antenna connected
>(I can just almost hear a signal that is 20 over 9 on
>my other receiver).
>Anything obvious? Is there a diode in the receiver antenna
>line to protect the front end that may have fried itself
>that I should check? (Is this part of the aux line too...
>the receiver can't hear through the aux antenna line either.)
>FAQ on WWW: http://www.contesting.com/tentecfaq.htm
>Administrative requests: tentec-REQUEST@contesting.com
FAQ on WWW: http://www.contesting.com/tentecfaq.htm
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