--- In ham_amplifiers@..., R L Measures <r@...> wrote:
On Oct 29, 2006, at 2:45 AM, pentalab wrote:
--- In ham_amplifiers@..., Tony King - W4ZT <w4zt-
060920@> wrote:
Pentalab wrote:
---
Some guy in W6 land wants me to design an amp around 3 x
YC-156's in parallel, GG... low band stuff. I figure with
600w of drive.. it should do 30-36 k out.
Wow... well if one tube isn't enough... you need a BIGGER tube!
I can't imagine dealing with the problems of paralleling 3 YC-
156's. He needs a 15k or 20k!
RICH SEZ.... Paralleling 3 tubes triples C-feedback, and that is
not desirable unless one is trying to build an oscillator. The
tube that is best suited for 20k - 35k out is the 8281/4cx15000A.
200w will drive one in AB1.
### So what ? Just install a globar type suppressor in each anode
lead. As is, the single YC-156 runs just fine wtih NO suppressor
at all.. and that's with it .75pf of feed through C to boot.
The single 3CX-3000A7 runs just fine sans suppressor with
it's .6 pf of feedthrough C. The 3CX-6000A7 has just .28 pf of
feedthrough C. We can probably toss the suppressor on that amp as
well. At this rate, we can put globar outa business.
### 3 x YC-156's is totally stupid.[11m ops have successfully
done it, they are obviously not stupid... maybe we should
invite a few of em to this group,
RICH SEZ.... guffaw
### well maybe not too stupid. 3 x YC-156's can be had for
$1100.00 vs huge bux for a 4 x 15.[plus socket]
### These YC-156/YC-179's.. with their almost 19db of gain.. are
the 4-1000 for the new milenium... quick, where's that pole pig ?
### I'm serious.... I think it would liven things up a bit... a
different perspective perhaps. When u start talking 20-35 kw
output... it's all.. 'illegal' anyway. Now don't start some
silly discussion about how 5 kw on 20m is... 'ok', but 10 kw on
11m is a 'no-no'. Rich... does a 8281 qualify as a....'Riley H
special' ? Me... I just boil oil. None of my tubes even have
handles. I asked Reid B, if they were gonna install handles on the
new YC-243... he wents nuts on me... said it would increase costs
through the roof..... so no handles for Jimbo here.
Later... Jim VE7RF
...
R L Measures, AG6K, 805.386.3734
r@..., , rlm@..., www.somis.org
