I am searching a low power linear amplifier to work portable, an all bands
linear, including WARC, very small and not too heavy.

Subsidiary question, are some of these linears able to work directly on a
12V battery and does it exist automatic models in this range of product ?

Even a 100-watt PEP HF amplifier is probably going to draw 20 amps or
more (peak) from a 12-volt battery. 500 watts PEP might peak out at
around 100 amperes. This is likely to pose a couple of problems...
the battery isn't going to last very long unless it's quite huge, and
(I^2)(R) losses in the wires are going to waste quite a lot of power
and generate a fair bit of heat.

The Ameritron ALS-500M might meet your needs... 500W max PEP, 400W CW,
1.5 - 22 MHz, optional kit extends it to handle 10 and 12 meters,
designed for mobile operations (3.5 x 9 x 15 inches, 7 lbs). It
requires 14 VDC at 80 amps for the finals, 14-16 VDC at 4 amps for the
rest of the circuitry, and somewhat less than 100 watts of exciter
power (for which you'll probably need roughly 15 amps to run your rig).

So, you're talking about a peak current draw of roughly 100 amperes.
A 100-amp-hour deep-cycle battery won't keep you going for very
long... a smaller gel cell would simply go URRGH and collapse instantly.

You might be able to use a deep-cycle battery, connected to and
constantly recharged by a vehicle's alternator. Hardly seems
"portable".

[I haven't used the Ameritron, or in fact any linear amp, so I can't
comment on its quality or reliability.]

Thierry
ON4SKY, LX3SKY
http://www.astrosurf.com/lombry/menu-qsl/

FYI, from here your main web-site page appears to be rather badly
broken. The GIFs for the buttons don't work, and clicking on the menu
items has no apparent effect. No matter what link I click on, it
seems to bring me back to the main page. That's with Mozilla 1.5 - it
may be that the Javascript on your pages, constructed with FrontPage,
are Microsoft-centric?

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
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