----- Original Message -----
From: <HOWARDLYON@aol.com>
To: <amps@contesting.com>
Sent: Sunday, July 10, 2011 3:51 PM
Subject: [Amps] 4-1000 GG project
> OK guys.... I need the wisdom of the ages... or is that aged? I dunno.
>
> Over twenty years in the making... well, that's when I got the bottle.
> Over the years I've collected the guts and small parts. It's time to put
> it
> all together.
>
> Basically adapting the parts that I have to the AA6GK design found on the
> Arkansas ARES/RACES site.
> _http://www.arkansas-aresraces.org/Equipment/Amplifiers/themanual.htm_
> (http://www.arkansas-aresraces.org/Equipment/Amplifiers/themanual.htm)
>
> A couple of questions:
>
> 1. Anybody have the specs on a PI-DUX 195-2 coil? Diameter, turns,
> length, AWG, etc?
>
> 2. The big question... his input net starts fine at 160m... 1820 puffs >>
> 10-15uH adjustable >> 1360 puffs on the output. Looks good as it breaks
> down to 1800p + 4.4uH = Z50 in : 9.7uH + 1360p = Z110 out.
>
> However, his 80m selection is more like 50 in and 60 out; 40m is 30 in and
> 50 out; 20m is 18 in and 30 out; according to his capacitor selection and
> the corresponding reactances and impedances
>
> I think he was winding coils to use whatever micas he had in stock. He
> has been unreachable via phone calls and e-mails to his mobile electronics
> business. Should I use his specs, or would I be better to scale the
> values
> more towards 50 in and 110 out?
>
> 3. Lastly, I have a 2H 1.6A monster choke for the HV PS. The tranny is
> 3600 rms @ 1 amp. About 5kV into the filter. Using 4 tubbies at 8uF/4kV
> in
> series / parallel for 8uF at 8kV with 2 100k/225W bleeders; the big
> choke;
> and then 14 390uF/450v lytics bridged with 14 50k 10Ws on the output.
>
> Ur thots on a resonating cap for the choke? The first bleeder current is
> about 25mA (about 125W)... might add an extra pair of 100k/100W to drop
> the
> heat; yea or nea?
>
> And, yes, I put new 150# casters on the rack.... the HV PS runs about 150
> pounds. ;-))
>
> Thanx for the help.
>
> Unca Billy
> N3TR
>
>
> Wm. H. Taylor
> General Contracting and Design
> 2249 Hickory Hill Rd
> Oxford, PA 19363
> 610-932-3762 h
> 484-643-3220 c
> n3tr@arrl.net
>
>
2. That a static value Howard that changes under drive and final values will
have to be determined in use. Many use a couple of BC style caps and a
roller inductor to get actual values, replace with fixed components and a
low value fine tune variable cap as "C2 tweak".
The published input R for a single 3-500Z is very close at 115 Ohms so you
can use them also from a published article
3. Toss the choke and caps and go with a string of electrolytics which are
cheap enough these days. With 12-13 470 or 560uF at 450V you will have
plenty of C and the 30-50K equalizers will be the bleeder. Trying to tune a
choke with junkbox values will be an exercise in frustration and
pyrotechnics. Fleabay is a good place to get high quality, recent date code,
surplus computer grade caps for short money. For the extra pennies use 6A10
(6A100 from some mfgs) diodes. I buy MCC brand from Mouser.
Carl
KM1H
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