[MAMS] Using Toshiba 3456 PA's in Rover

[Lloyd Ellsworth]

Jim,

I run one. Have run one for about 10 years. Big thing is keeping the
operating voltage close to the recommended 12.6V. Rover I run mine off
a car battery. Not stopped, charge the battery. Set up, just the
battery. That way I don't run the car battery down.The Class A amp,
draws quite a few amps. Like 6-9 Amps, if my memory serves. Key down
full output, and no output idle, is not much difference in current
draw. Higher constant voltage source, suggest a dropping resistor. Big
heat sink is important. Add airflow. Running higher voltage, the amp
gets really hot, really quick. Goes into self destruct mode.

My home unit, usually is, or will be next year, on top of the tower,
near the antenna. I run a separate power supply for it. Separate power
cable up the tower. Set for 12.6V at the amp. Thing is, 12.6V high
current zeners or regulators are not all that common. Next trick,
don't overdrive it.

I destroyed one. Too small a heat sink. Ran it too long. Then I
acquired 2 other dead amps. So, I have a few spare parts. Rover amp,
will run 22W, I have it set for about 18W. Hopefully run longer.
WA8VPD/r runs one. This amp has really helped 3.4 GHz activity.

I have heard of several of them run ATV, ATV repeaters.

73, Lloyd NE8I/r
EN73 etc

On Wed, Nov 23, 2011 at 9:36 PM, W9SNR - Jim <w9snr at comcast.net> wrote:
> Lloyd,
>
> I have one of the Toshiba 20 W 3456 PAs which I plan to use for a new rover station.  I wonder if you have had any experience powering the Toshiba PA from a car's "13 V" electrical system.  I hear that these PAs are rather finicky about supply voltage, so I'm looking for any suggestions on how to avoid blowing it up.  I've only got one PA, and the prospects for getting another one don't look too good.
>
> 73 - Jim
> W9SNR
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