According to the manual -- The scout uses an LM2940T - 10 volt regulator.
I've used the Scout in my van with a pair of deep cycle marine batteries.
But it's not at all happy when the battery voltage goes from 13.8 volts and
approaches 12 volts. I've actually worked sideband as low as 11.8 but then
the roof falls in.
Rick
VE7ASR
-----------------------
To: <tentec@contesting.com>
Date: Sun, 10 Dec 2000 10:55:38 -0600
From: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@ames.net>
Subject: Re: [TenTec] TT Scout on batteries?
Sounds to me as if the Scout has a 7810 or LM340-10 regulator for the
VFO. That regulator needs about 2.5 volts headroom input to output to
maintain regulation. Very likely the TO-92 version 78L10. I have no
Scout and no scout manual to see. Perhaps that regulator could be
replaced by a LM2937ET-10 or LM2940-10 or a series resistor and a TL431
family programmable zener diode. The LM29xx family works with down to
0.6 volts drop, the TL431 would work lower though a bit less efficiently
than the series regulator. The TL431 programmable zener diode is a far
better regulator than any plain zener diode.
73, Jerry, K0CQ
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