Hi John,
Probably a better/easier solution to amplifier output protection would be to
add a circulator on the output with a proper dummy load. This would let the
amp always see a good 50 Ohm load and protect against high SWR. You could
even monitor the reflected power port if necessary. I see high power
circulators on ebay from time to time that cover the 144 MHz band - or close
to it that will work for you. Motorola uses them in some of their high power
base stations that will handle ~350 Watts and not too big a box, 5 x 5 x 2
inch with N connectors, you add the dummy load.
73,s
George, WA2VNV
----- Original Message -----
From: "John D'Ausilio" <jdausilio@gmail.com>
To: "(Radio) VHF Contesting" <VHFcontesting@contesting.com>
Sent: Monday, October 12, 2009 11:08 AM
Subject: [VHFcontesting] repairing TE amp - matched quad required?
So I'm thinking about how to get my TE 400W 2m amp back online. I see
some new MRF-247s on ebay for a reasonable price, will I run into
trouble if these are not a matched quad?
On an unrelated topic .. has anyone considered or performed a
replacement of the output combiner with something that would offer
more protection in the event of a mismatch?
de w1rt/john
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