[TenTec] Airpax

[John K Gotwals]

I had the same thing happen to me with my Orion 565. Like you, I had 
installed an Airpax breaker between my Orion and an Astron 35 amp linear PS. 
In my case I made the unforgivable error of trying to operate my Orion at 
full power tune-up, but with the coax antenna feed disconnected from the 
Orion. Like you, the Airpax flipped into the off position, and everything 
still worked properly after reconnecting the antenna connection and 
resetting the Airpax breaker.

Shortly after posting an account of my error and its correction on this 
reflector, I received a series of entertaining email messages from a 
cantankerous ham who quoted in great detail from the schematic diagram for 
the Orion, while claiming that what you and I had both observed was 
impossible, and therefore we were confused!

John, N9JG

= = = = Original Message = = = =
Date: Thu, 29 Mar 2007 20:33:35 -0400
From: "Robert Carroll" <w2wg at comcast.net>
Subject: [TenTec] Airpax
To: "'Discussion of Ten-Tec Equipment'" <tentec at contesting.com>
Message-ID: <008101c77263$0ddd3c80$6c01a8c0 at VISION>
Content-Type: text/plain; charset="us-ascii"

At the risk of reigniting a hot topic, this morning I developed a sudden SWR
problem while running barefoot this AM.  I was running 100W from my Orion
565 when I saw my digital meter jump up to around 4:1 SWR  and the Airpax
breaker I had "protecting" the Orion (Astron supply) tripped for the first
time ever.  Holding my breath, I turned the Orion power switch off and reset
the Airpax.  To my great relief all was well-or at least it seems to be 12
hours later.  No fuse in the Orion blew.  I understand there is a protection
circuit in the Orion which eliminates the need for an external breaker.
Perhaps that would have protected the finals, but it didn't prevent the
Orion from sucking enough current to trip the Airpax and that makes me
wonder if I would have been packing the set up for shipment to TN if the
Airpax had not been in line.  I have never been convinced that the Airpax
was necessary, but when it clicked off, I was very glad I had installed it.



I never did find anything wrong with the antenna system, and I ran at legal
limit calling the 3B1 this AM with no problem.  I did go out this afternoon
and spray some Caig on two connectors and a barrel.  But there may be a
problem waiting to reappear.



FWIW

73

Bob W2WG