WTB: Hercules 444 damaged amplifer
 

Interested in buying a blown up 444 TenTec PA.
Price accordingly.
Jim

On Fri, 12 Mar 2004 01:19:42 GMT, "Jim Warner"
wrote:

Interested in buying a blown up 444 TenTec PA.
Price accordingly.
Jim


Do you have a way of repairing them?

The final transistors have long been discontinued.
Ten-Tec themselves have said that they can't get one working with
modern replacements without a total redesign of the amp.

Apparently its a problem of the gain(HFE) of the modern devices not
being compatible with the feedback methods used. They can get it right
on some bands but not on others.

Others I've talked with have confirmed this - not just Ten-Tec.

Doug

Doug wrote:
On Fri, 12 Mar 2004 01:19:42 GMT, "Jim Warner"
wrote:

Interested in buying a blown up 444 TenTec PA.
Price accordingly.

Do you have a way of repairing them?

The final transistors have long been discontinued.
Ten-Tec themselves have said that they can't get one working with
modern replacements without a total redesign of the amp.

Apparently its a problem of the gain(HFE) of the modern devices not
being compatible with the feedback methods used. They can get it right
on some bands but not on others.

Others I've talked with have confirmed this - not just Ten-Tec.

I would think that it would be a nice box for a homebrew amp, though.
You get a cabinet, a power supply, and a bunch of tuned tank circuits that
you can keep. And I would assume that they would basically be available
for the asking at the end of the day at a hamfest, if they are indeed
unrepairable.

What output devices do they normally use? Are they wacky germanium types?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."