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Yaesu FL-110 and Kenwood TL-120 both should work reasonably
well. They were designed for the JA 10 watt era rigs but
the FT-817 should drive either to close to full output
(and leave a bit of headroom.)

73 Dave WB0GAZ wb0gaz@... (hotmail really sucks)

From: "John O. Newell" <jnewell@...>
Reply-To: FT817@...
To: FT817@...
Subject: [FT817] Amp for FT-817?
Date: Fri, 27 Oct 2000 19:51:20 -0400

Not trying to dis QRP, but if I wanted to run an amp with this rig down in
the HF frequencies, does anyone have any idea what we'd run? A CB amp was
suggested to me, but I can't find any that are less than around 150A...was
thinking more like 50A.

73
John Newell
KB1FPM

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Not trying to dis QRP, but if I wanted to run an amp with this rig down in
the HF frequencies, does anyone have any idea what we'd run? A CB amp was
suggested to me, but I can't find any that are less than around 150A...was
thinking more like 50A.

73
John Newell
KB1FPM

build an amp - use a Motorola Engineering Bulletin. Get the parts and boards
from Communications Concepts in Beavercreek OH (near Dayton).
They have a couple nice boards, toroid kits, chip cap kits for an amp using
a pair of MRF454's. They also have a 28v kit as well as the ability to
parallel MRF454 boards.

Bob

At 20:00 27/10/00 -0400, you wrote:

build an amp - use a Motorola Engineering Bulletin. Get the parts and boards
from Communications Concepts in Beavercreek OH (near Dayton).
They have a couple nice boards, toroid kits, chip cap kits for an amp using
a pair of MRF454's. They also have a 28v kit as well as the ability to
parallel MRF454 boards.

I've worked with these transistors but they are a bit of over kill. I also
thought that Motorola was phasing them out!
This is boosted by the fact that they dont include data of them on their
web pages any more

I have uploaded a pdf file of the MRF148A which is a 30W MOSFET
unfortunately it works on 50V. However I would say making a 50V supply is a
trivial task to building the PA.
2 of these in push pull with a slight modification to their cct would work
nicely I think.
Thats the whole spirit of Amateur radio get in there and tinker.
I would recommend making band pass filters for the PA as you will be
generating lots of harmonics!

Cheers
Eric.

-----------------------------------------------------------------
Eric Freund, Engineer.
Oilphase, Schlumberger Oilfield Aust P. L.
23 Brennan Way, Belmont,
Perth, Western Australia, 6104.

Tel : +61 8 9277 2000 Mo: +61 41 331 9396
Fax: +61 8 9277 3222
mailto:freund@...
-----------------------------------------------------------------

Subject: Re: [FT817] Amp for FT-817?

build an amp - use a Motorola Engineering Bulletin. Get the parts and

boards

from Communications Concepts in Beavercreek OH (near Dayton).
They have a couple nice boards, toroid kits, chip cap kits for an amp

using

a pair of MRF454's. They also have a 28v kit as well as the ability to
parallel MRF454 boards.

Wow, they make nice stuff. About a hundred years ago I built a 2m amp. Super
nice. I am glad to hear they have PCB kits for ( hopefully ) a wide-coverage
HF linear that takes the FT-817 type drive and beefs it up.

What sort of output do you contemplate... and would it be no-tune? He asked
hopefully but not really expecting...

Pres Waterman W2PW
c/o Patchogue Motors, Inc.
Long Island Ford and Kia Dealer

GO BILLS!

What sort of output do you contemplate... and would it be no-tune? He asked
hopefully but not really expecting...

Most Multi Octave, HF PA systems get away with broad band matching
transformers. Hay HF is practically DC compared to UHF and above. Its easy
to get away with simple no tuning design.
I would recommend you use an output filter though as especially with
Bipolars you will have harmonics to day light. the second 3rd and 5th will
be huge. (hay multi band operation in one hit!!!)

Cheers
Eric.

-----------------------------------------------------------------
Eric Freund, Engineer.
Oilphase, Schlumberger Oilfield Aust P. L.
23 Brennan Way, Belmont,
Perth, Western Australia, 6104.

Tel : +61 8 9277 2000 Mo: +61 41 331 9396
Fax: +61 8 9277 3222
mailto:freund@...
-----------------------------------------------------------------

What sort of output do you contemplate... and would it be no-tune? He

asked

hopefully but not really expecting...

Most Multi Octave, HF PA systems get away with broad band matching
transformers. Hay HF is practically DC compared to UHF and above. Its easy
to get away with simple no tuning design.
I would recommend you use an output filter though as especially with
Bipolars you will have harmonics to day light. the second 3rd and 5th will
be huge. (hay multi band operation in one hit

Uh, please define the term "hay" in this context... do you mean "hey" as in
"hey there"...? Or something else?

Pres Waterman W2PW
c/o Patchogue Motors, Inc.
Long Island Ford and Kia Dealer

GO BILLS!

At 23:21 27/10/00 -0400, you wrote:

Uh, please define the term "hay" in this context... do you mean "hey" as in
"hey there"...? Or something else?

Sorry Hey! If it sounds the same I spell it the same no need to remember
useless words!
at HF all your impedance matching is practically real and so you can get a
way with just matching transformers!

Cheers
Eric.

-----------------------------------------------------------------
Eric Freund, Engineer.
Oilphase, Schlumberger Oilfield Aust P. L.
23 Brennan Way, Belmont,
Perth, Western Australia, 6104.

Tel : +61 8 9277 2000 Mo: +61 41 331 9396
Fax: +61 8 9277 3222
mailto:freund@...
-----------------------------------------------------------------

I just bought a solid state amp from the han store in san Anatonio Tx that takes a max of 20 watts drive for upto 500 watts out. Haven't tried it yet. When I do I will post and let you know how it works. it covers 10-160 metters and comes in "kit" form. The Ham Store e-mail is kcomm@... Ask for MelWA5UTK. They have sold over a hundred of these amps. Mike NH6CJ

From: "John O. Newell" <jnewell@...>
Reply-To: FT817@...
To: FT817@...
Subject: [FT817] Amp for FT-817?
Date: Fri, 27 Oct 2000 19:51:20 -0400

Not trying to dis QRP, but if I wanted to run an amp with this rig down in
the HF frequencies, does anyone have any idea what we'd run? A CB amp was
suggested to me, but I can't find any that are less than around 150A...was
thinking more like 50A.

73
John Newell
KB1FPM

_________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at .

Share information about yourself, create your own public profile at .

Ramsey makes a line of QRP linears for about $50 each.