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[Amps] 222 MHZ 8877 Amp Design Needed

To: <amps@contesting.com>
Subject: [Amps] 222 MHZ 8877 Amp Design Needed
From: sraas at rochester.rr.com (Steven Raas)
Date: Tue May 27 08:40:41 2003
Dear Bill C. N2BC and All others whom have emailed me...

        I just had a free moment to look at that web site iu sent me abt the
EZ tuner! Wow.. ok .. im adding that to my project list... i could see a
retail market 4 that ALL DAY LONG.. anyways.......I think that alot of the
ideas incorporated in that, are a lil over kill for what i need.. so what I
basically did.. was think long and hard abt what I consider remote
functions.. and what EXACTALLY I want..

So far Ive come up with this....

I want 2 sets of metering ,( including power out, yes this will cost me 400+
dollars more.. i dont care)  1 set on the amp deck itself.. and 1 at the
operating position.. that work at the same time in unison.

I want to have 2 HV switches ( to activate / deactivate the HV ) 1 on deck
one on remote panel

I want Temperature metering , both on the deck and remote ( digital )

I want STBY / OPERATE (2) same as above 1 on deck one on remote...

Now.. my big question is.. the switches can be done as far as i know
easily...
But the dual metering.. Im not so sure that can be done.

I also want to incorperate some sort of variable or 2 speed blower
function...
reason: some times i just wanna talk for a few minutes.. no need to blow 60
cfm threw the socket.... but when its contest time.. i wanna be dam sure i
have the ability to cool that tube, under some serious duty operation. ( YES
WSJT WILL BE USED OFTEN @ 1500 pep those are long key down modes if not
familliar ) 30 seconds on 30 seconds off.. for many hrs at a time .

Now as far as actual tuning controls.. I have recieved many many emails..
and I thank you ALL.. and have decided that once this amp it tuned.. and
running for a short amnt of time.. that retuning.. will be ALMOST un
necessary. So I have 86'ed the need for that on my " remote panel idea "

To sum it up, and mabey any one else reading this may be able to come up
with some more ideas.. is I want to be able to know EXACTALLY whats going on
with this amp at all times... I may even incorporate not only FWD RF out
metering.. but also REF RF metering... simultaniously.. yes turning the slug
reverse is just as easy... but when ur spending 30 minutes playing with a
weak one.. trying to dig him out.. i dont want another dial to turn.. i
wanna LOOK and be INFORMED of the stations performance instantally, and
continue at task at hand.

I will be drawing a preliminary ' front panel lay out '  of what i think i
want.. any ideas from any one are SUPER and please keep them comming.

Ohh and another foot note.. I only have 2 hand books  1989 & 2000,  but If
memory serves me corectly the 1989 edition has a 8877 design.. i may begin
with that as a starting point. But befor i even collect 1 single part (
thats a lie cause i have some already ), i want to get the design in stone..
and all my extras in stone and designed as well, i dont want any ' whoop'ses
that wont work ' after i begin to build.

Ty Bill And Every one else!

Steve Raas
N2JDQ



----- Original Message ----- 
From: "Bill Coleman N2BC" <n2bc@stny.rr.com>
To: "Steven Raas" <sraas@rochester.rr.com>
Sent: Saturday, May 24, 2003 10:58 AM
Subject: Re: [Amps] 222 MHZ 8877 Amp Design Needed


> Hi Steven, thought I'd pass along some random thoughts - nothing specific
to
> the trials and tribulations of building a UHF amp though.  In other words,
> take this, add a buck or so and you may be able to get a coffee out of it
!
>
> Nothing much has changed in the RF end of things for decades.  That's why
> you don't see much difference when you look back at designs from the 80s
or
> 70s or 60s.   Materials have improved - things like teflon, the tubes have
> improved - coaxial construction, etc. but the RF end of things is pretty
> well defined.
>
> Where there have been big changes is the control and protection circuits.
> Maybe just what you are looking for in terms of remote capability.  With
the
> advent of small and dirt cheap stepper motors and programmable controllers
> it is quite possible to do a lot of automation.  I'm not sure this is
> necessary in a single band amp, but it sure would be fun to play with.
>
> I would recommend you look at W8ZR's "EZ-Tuner" for ideas.
> http://www.miami.muohio.edu/president/personal/w8zr/eztuner/index.htm  He
> uses a Basic STAMP controller which 'sniffs' the input RF, determines
> frequency, does bandswitching and controls stepper motors to twist
variable
> caps. Many of the ideas and circuits are 'portable'. In fact, I am
> plagiarizing a lot of this for an HF amp project I am working on.
>
> An 'intelligent' controller like this could easily handle power up/down
> sequencing, sense voltages, currents, temperature - provide all the basic
> control and protection that any amp needs.
>
> Like I said, no specifics - but maybe the germ of an idea or two.
>
> HAVE FUN!!
>
> 73, Bill
> ~~~~~~~~~~~~~~~~
> Bill Coleman    N2BC
> http://home.stny.rr.com/n2bc
> ----- Original Message -----
> From: "Steven Raas" <sraas@rochester.rr.com>
> To: <amps@contesting.com>
> Sent: Friday, May 23, 2003 7:34 PM
> Subject: [Amps] 222 MHZ 8877 Amp Design Needed
>
>
> Hello Everyone,
>
>                                 I am in the midst of looking for a ROCK
> SOLID NO JOKE 222mhz amp design. I have a powersupply in mind.. so I'm all
> set there.  Has any one ever tried to incorporate a remote panel for amp
> adjustments?? This sure would be handy, as this deck would sit in a rack
> some what near the op-possition, but not conviently NEXT to it. IE. remote
> metering functions.. ect... ?  I am looking to use ONLY the 8877
3xc1500A7,
> Yes I am aware of the russian tubes.. ect.. im not interested.
>
> This amplifier will be used for heavy duty weak sig work, durring
contests,
> and possible EME down the road. I have seen the amp designs in the hand
> book.. their nice.. yes, but their the same designs i've seen in the hand
> book for 14 years. Im hoping that I will find some sort of  ' LATEST AND
> GREATEST DESIGN '.
> I want to build this puppy from scratch.. using the best possible parts I
> can find, and incorporating my NEEDS ie. the remote panel ect.
>
> Also, this amp need only tune 222-222.5 there is absolutly NO NEED fo any
> more bandwidth.. Im hoping that in it only needing to be very narrow
> bandwidthed, that I can incorporate some pretty nice filtering in the
> output. Time is no object.. money is to an extent.. I just wast all the
> resources I can grab ahold of before I start making desisions. So in
> closing... If you know some one who built an amp for 222 that is just a
rock
> solid performer.. please pass any information along to me. I am aware that
I
> could go buy a lunar link for many $$$, but ide rather spend the same
amnt.
> of $ and have the pride of saying I BUILT THAT and it works like a champ!
>
> Ty for ur time.
>
> Steven J. Raas
> N2JDQ
>
> email -  sraas@rochester.rr.com
>
> 73's gud dx tu
>
>
>
>
>
>
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