For higher power I use 3/8" on 160m, 1/2" on 80+40m, followed by ~3/4" on
the higher bands.
I do my silver plating with a homebrew mixture.
When I had no other stuff on hand, I once used sugar to fill the copper tube
before winding it, gave a nice smell after firing it up at high power, as
not all went out that easy ;-).
For much less then 8K I built 6 monobands amps 5K out.
I always prefer tetrodes...
73
Peter
________________________________
From: ham_amplifiers@... [mailto:ham_amplifiers@...]
On Behalf Of pentalab
### LOL ! I typ use 1/4" 3/8" and 1/2" [6-9-12 mm od]
### chek out what Multronics wants for say 1/2" tubing coil
stock... like a 14 uh coil.... you will gag.. and have sticker
shock. $8,000 for a new alpha. I can buy a helluva lots
parts for $8 K.
### You don't need much tubing to wind a typ tank coil. I used
1/4" for the 160m portion...... 3/8" for the 80-40m coil.....
and 1/2" for the 20-17-15m coil. Anybody who is thinking of
using these big triodes on 10/12 m... is well advised to use 3/4"
tubing... or 1.5" wide strap. [typ 2-3 turns.. 3" ID used on
10/12m]
### They are easy to silver plate too... with "cool amp" from
Ore. 3/8" and up will flatten on you, when wound... width is
greater than the height. [looks cool] If u want it perfectly
round..... fill the tubing with either rocksalt.. or sand b4 u
wind the coil. Use an air compressor to blow out the sand when
done. With rocksalt..... just toss the completed coil in
water... and let it disolve.
Later....Jim VE7RF
________________________________
From: ham_amplifiers@...
<mailto:ham_amplifiers%40yahoogroups.com>
[mailto:ham_amplifiers@...
<mailto:ham_amplifiers%40yahoogroups.com> ]
On Behalf Of pentalab
and it's all dirt cheap....just like copper tubing.
