When mine caught fire, they had to fabricate two new boards I believe. The
closest transistors they could get to the originals had higher gain and were
thus more prone to self-oscillation (the malady that started the fire in my
amp). They lowered the gain with minor circuit modifications but cautioned
me that they wouldn't work on it or any other Hercules 444 in the future.
This was *well* over 10 years ago, probably 15-18 years. I didn't own that
amp very long.
I sold it to a fellow who intended to remove the RF strips and replace them
with some Motorola units. I don't know if he did that or not but it would
be an excellent change.
73 and Merry Christmas,
Mike N4NT
----- Original Message -----
From: "Graham Wright" <graham-g4fuj@talk21.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Thursday, December 22, 2005 4:16 AM
Subject: Re: [TenTec] Hercules 444 amp
I don't have diagrams or info. on these, but surely
there must be a nearish equivalent transistor to use
in the finals on these, even if some modification is
required to driver stage and PSU?
73
Graham G4FUJ
--- Clark Savage Turner <csturner@kcbx.net> wrote:
> Correct me if I'm wrong:
>
> - The Hercules 444 amp was declared unrepairable at
> least 10 years ago
> due to the inability to obtain the proper
> replacement final
> transistors.
>
> - The Hercules II is still easily repaired as the
> finals are readily
> available (and even a good sub exists as I
> understand it.)
>
> Clark
> WA3JPG
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