[TenTec] Hercules 444 amp

[Paul Gentry]

If you have plenty of time and like to build, you can put an amp together
from sources such as Communications Concepts (CCI
<http://www.communication-concepts.com/index.php/amplifiers.html>).  The
basic amp is easy, it's the filters, switching, and controls we want these
days (auto band switching, etc.) that cost the $$$.  I have looked at this
but after all the labor, parts, etc. the price of a new or used
commercially manufactured amp (like the Elecraft, MFJ, etc) look pretty
good.

SGC is not currently producing it's 500W cube amp because of discontinued
parts.  Just like the Orion II, you can't produce a product indefinitely
because of parts sourcing limitations.

Paul
*Paul Gentry*
K4BWG
  <http://en.wikipedia.org/wiki/Tux>


On Sat, Aug 9, 2014 at 5:38 PM, Brian Carling <bcarling at cfl.rr.com> wrote:

> So maybe the Hercules can be converted to use MOSFETs. Seems like it
> should be possible.
>
> I also think MFJ needs some competition on MOSFET linear amplifiers to get
> the price point within reach of the average ham.
>
> There is just not a good reason why so many linear amplifiers should cost
> $3500 to $9500 when you look at the parts cost and manufacturing cost.
>
> [/SOAPBOX]
>
> Best regards - Bry Carling
>
>
>
> > On Aug 9, 2014, at 5:24 PM, Douglas <sparks06524 at yahoo.com> wrote:
> >
> >
> > Date: Sat, 9 Aug 2014 10:12:45 -0400
> > From: Brian Carling <bcarling at cfl.rr.com>
> > To: "k9yc at arrl.net" <k9yc at arrl.net>,
> > Discussion of Ten-Tec Equipment
> >     <tentec at contesting.com>
> > Subject: Re: [TenTec] Hercules 444 amp
> > Message-ID: <86F80EE5-1044-42AA-9641-D8859123467B at cfl.rr.com>
> > Content-Type: text/plain;
> > charset=us-ascii
> >
> > Seems like a lot of RF power transistors are similar, so it
> > should not be too difficult to find a substitute.
> >
> > Best regards - Bry Carling
> >
> > ------------------------------------------------------------
> >
> > Ah -  but it is hard to find a substitute. The Ten-Tec factory can't
> find one.
> >
> > There were only a few designs of 250 to 300 watt 50V bi-polar power
> transistors made. The remaining ones are hard to get and have an HFE that
> is too high. Several such transistors have been totally discontinued.
> Motorola for example is out of that business. M/AComm bought some of their
> designs but in general bi-polar RF transistors are considered passe. RF
> MOSFETS are now the name of the game.
> >
> > Per another poster: I've not had trouble with the power supply drifting
> upward with temperature rise. Perhaps they solved that with compensation.
> >
> > 73,
> >
> > Doug/WA1TUT
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