If you read the TT documentation, there are two kinds of high SWR. For a 3:1
SWR you can have a reactance of 16 (1/3 of 50) or 150 (3 times 50) ohms. If
you have a high reactance, the final current will drop (I = E / R), but if
you have a low reactance the current will go up. Perhaps you've been lucky
in that all your high SWR situations have been high reactance as opposed to
low. Just a thought.
----- Original Message -----
From: "Duane A Calvin" <email@example.com>
Sent: Friday, August 17, 2001 6:56 PM
Subject: Fw: [TenTec] Power supply overcurent
> I have run my Omni VI+ on an Astron RS35M for the last 4 years, often
> firing full power into high-SWR loads, and have had no problem with the
> finals. I usually try to adjust the tuner at low power, but have, on a
> number of occasions, switched antennas or bands and forgotten to retune.
> I usually see it within a minute or so, but not after transmitting into a
> "bad load." Don't try this at home, kids, and maybe I've just been
> lucky, but I notice the manual says nothing about requiring this breaker
> if a non-TT supply is used. FWIW....
> 73, Duane
> Duane A. Calvin, AC5AA
> Austin, Texas
> firstname.lastname@example.org -or- email@example.com
> Day: firstname.lastname@example.org
> --------- Forwarded message ----------
> From: Gary Gaudette <email@example.com>
> To: "Tentec, Users" <firstname.lastname@example.org>
> Date: Fri, 17 Aug 2001 21:07:56 +0000
> Subject: [TenTec] Power supply overcurent
> Message-ID: <3B7D87AC.220700F4@vgernet.net>
> I disagree with the statement that a magnetic circuit breaker is not
> required with the OMNI V or VI. Many times in the 10 years or so that I
> owned an OMNI V I tripped the one in my 961 P/S. Never had a bit of
> damage to the rig so it must have done it's job.
> In the 3 years that I have owned an OMNI VI I tripped it a half dozen
> times or so. Again no damage to the rig.
> I have a friend that is using a big Astron supply with his OMNI VI who
> has gone through four sets of finals. I have suggested that the purchase
> of a breaker might be a good idea.
> Oh, my problems were all caused by operating at full power into antenna
> systems with SWR's of over 3:1, I'm lazy at times and usually reduce
> power vice tuning the transmatch when it is needed!
> 73, Gary, W1GG
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