100W HF power amplifier
 

Hi all;

I plan to build an HF power amplifier, output about 80-100W, not critical.
It might look like as those used in popular Yaesu, Kenwood or Icom end PA
stages, i.e. first stage as driver and the second as final amp., both in
push-pull, transformer-separated. It should run directly with 13.8V supply.
Of course, everything based on popular transistors as MRFxxx, 2SCxxxx,
2SDxxxx, IRFxxx MOS or russian (would be the best, since there are no
problems with buying ones in my country). I've spend several evenings
searching in googles, but I've failed to find anything suitable for me.
Either I'm such a demanding person, or missed something while looking up in
endless vastness of the internet. If anyone knew a well-designed project, or
built one whenever in past, it would be welcome.

TIA

--
Pawe³ Stobiñski SQ9NRY
Republic of Poland

On Sat, 11 Oct 2003 20:58:22 +0200, "Pawe³ Stobiñski"
wrote:

Hi all;

I plan to build an HF power amplifier, output about 80-100W, not critical.
It might look like as those used in popular Yaesu, Kenwood or Icom end PA
stages, i.e. first stage as driver and the second as final amp., both in
push-pull, transformer-separated. It should run directly with 13.8V supply.
Of course, everything based on popular transistors as MRFxxx, 2SCxxxx,
2SDxxxx, IRFxxx MOS or russian (would be the best, since there are no
problems with buying ones in my country). I've spend several evenings
searching in googles, but I've failed to find anything suitable for me.
Either I'm such a demanding person, or missed something while looking up in
endless vastness of the internet. If anyone knew a well-designed project, or
built one whenever in past, it would be welcome.

Why not just copy a suitable proprietory schematic? What's the problem
with that?
--

"Windows [n.], A thirty-two bit extension and GUI shell to a sixteen bit patch
to an eight bit operating system originally coded for a four bit
microprocessor and produced by a two bit company."

On Sat, 11 Oct 2003 20:58:22 +0200, "Pawe³ Stobiñski"
wrote:

Hi all;

I plan to build an HF power amplifier, output about 80-100W, not critical.
It might look like as those used in popular Yaesu, Kenwood or Icom end PA
stages, i.e. first stage as driver and the second as final amp., both in
push-pull, transformer-separated. It should run directly with 13.8V supply.
Of course, everything based on popular transistors as MRFxxx, 2SCxxxx,
2SDxxxx, IRFxxx MOS or russian (would be the best, since there are no
problems with buying ones in my country). I've spend several evenings
searching in googles, but I've failed to find anything suitable for me.
Either I'm such a demanding person, or missed something while looking up in
endless vastness of the internet. If anyone knew a well-designed project, or
built one whenever in past, it would be welcome.

Why not just copy a suitable proprietory schematic? What's the problem
with that?
--

"Windows [n.], A thirty-two bit extension and GUI shell to a sixteen bit patch
to an eight bit operating system originally coded for a four bit
microprocessor and produced by a two bit company."

On Sat, 11 Oct 2003 20:58:22 +0200, "Pawe³ Stobiñski"
wrote:

Hi all;

I plan to build an HF power amplifier, output about 80-100W, not critical.
It might look like as those used in popular Yaesu, Kenwood or Icom end PA
stages, i.e. first stage as driver and the second as final amp.
snipped

Have you looked at Motorola's website?. There are a good number of
Application Notes there with amps from 10w to Kw's for HF to uWave
described in detail. There is also a company in US that stocks the
'hard to find' bits, and Kits, for them. Sadly I can't find the URL at
the moment.

On Sat, 11 Oct 2003 20:58:22 +0200, "Pawe³ Stobiñski"
wrote:

Hi all;

I plan to build an HF power amplifier, output about 80-100W, not critical.
It might look like as those used in popular Yaesu, Kenwood or Icom end PA
stages, i.e. first stage as driver and the second as final amp.
snipped

Have you looked at Motorola's website?. There are a good number of
Application Notes there with amps from 10w to Kw's for HF to uWave
described in detail. There is also a company in US that stocks the
'hard to find' bits, and Kits, for them. Sadly I can't find the URL at
the moment.

Could be RF Parts?

http://www.rfparts.com/mototran.html

- Bruce Raymond/ND8I


"Mike W" wrote in message
...
On Sat, 11 Oct 2003 20:58:22 +0200, "Pawe³ Stobiñski"
wrote:

Hi all;

I plan to build an HF power amplifier, output about 80-100W, not
critical.
It might look like as those used in popular Yaesu, Kenwood or Icom end PA
stages, i.e. first stage as driver and the second as final amp.
snipped

Have you looked at Motorola's website?. There are a good number of
Application Notes there with amps from 10w to Kw's for HF to uWave
described in detail. There is also a company in US that stocks the
'hard to find' bits, and Kits, for them. Sadly I can't find the URL at
the moment.

Could be RF Parts?

http://www.rfparts.com/mototran.html

- Bruce Raymond/ND8I


"Mike W" wrote in message
...
On Sat, 11 Oct 2003 20:58:22 +0200, "Pawe³ Stobiñski"
wrote:

Hi all;

I plan to build an HF power amplifier, output about 80-100W, not
critical.
It might look like as those used in popular Yaesu, Kenwood or Icom end PA
stages, i.e. first stage as driver and the second as final amp.
snipped

Have you looked at Motorola's website?. There are a good number of
Application Notes there with amps from 10w to Kw's for HF to uWave
described in detail. There is also a company in US that stocks the
'hard to find' bits, and Kits, for them. Sadly I can't find the URL at
the moment.

Paul Burridge wrote:
Why not just copy a suitable proprietory schematic? What's the problem
with that?

Yes, that's a good idea, however it is not always possible to decipher
values of the elements, number of turns, type of magnetic material and so
on. You cannot determine board layout, either. I believe it is relevant to
the circuit not to start oscillating.

--
Pawel Stobinski SQ9NRY
Republic

Paul Burridge wrote:
Why not just copy a suitable proprietory schematic? What's the problem
with that?

Yes, that's a good idea, however it is not always possible to decipher
values of the elements, number of turns, type of magnetic material and so
on. You cannot determine board layout, either. I believe it is relevant to
the circuit not to start oscillating.

--
Pawel Stobinski SQ9NRY
Republic

Mike W wrote:
Have you looked at Motorola's website?. There are a good number of
Application Notes there with amps from 10w to Kw's for HF to uWave
described in detail. There is also a company in US that stocks the
'hard to find' bits, and Kits, for them. Sadly I can't find the URL at
the moment.

Thanks!

--
Pawe³ Stobiñski SQ9NRY
Republic of Poland