[TenTec] battery life

[k6kdk at k6kdk.net]

> The original question was concerning the use of a car battery,

You need a voltage stabilizer:

There are a number of sources for these
W4RRY made a design that was published in QST;

October 2005 QST Product Reviews and Short Takes  [PDF]
... to be the case, but as often happens, the devil is in the details. W4RRY
Electronic
Battery Booster Table 2 W4RRY Battery Booster Output as a Function of Input
...
www.arrl.org/members-only/prodrev/pdf/pr0510.pdf

Leo Lehner 5811 E Crocus Dr Scottsdale AZ 85254 See the QST Article: I thnk
he still sells them. You can email him or inquire otherwise.

QST November 2004 has the details

 It has a low voltage cut out at 11 Volts and you can activate it using
control line from your rig. It can also sense RF and boost automatically. It
is RF tolerant and emits no HF noise, its a switchmode design.

Also a ready built commercial model:

http://www.powerstream.com/dc-buck-boost.htm

also see:

http://stores.tgelectronics.org/default.htm