Rich;
I own an Alpha 77 (not a D) and the bottom end of the Pi-L is 3Mhz.
What's with 160 meters ? Did some 77s cover 160.. I thought the later
"D" models did but not the 77 ?
Peter Gerba
pgerba@crl.com
On Sat, 2 Aug 1997, Rich Measures wrote:
> >> From: Rich Measures <measures@vc.net>
To: <amps@contesting.com>
> >> Date: Sat, 2 Aug 97 21:36:24 +0000
> >>
> >> Adding the extra tube is relatively easy. Correcting the ramifications
> ><SNIP>
> >> adding a second tube is filter-C failure. When the second tube is added,
> >> the 120Hz ripple current in the hv filter C doubles, which in turn
> >> quadruples the (P=I^2*R) dissipation in the filter capacitor. Mostly
> >> during contesting, case seams sometimes split and the oil leaks out.
> >> Peter W. Dahl reportedly has a retrofit upgrade.
> >> -It adds up to a lot of dollars, grief, time, and less than a half
> >> S-unit.
> >
> >Strange.
>
> You thought period=1/frequency and frequency=1/period was strange
> >
> >I just looked at a bone stock tank two tube Alpha conversion and it
> >worked just fine.
> >
> In serious contesting service? .......With the stock tune-C and 2-holer
> conversion, the tank Q is under 6 on 160m. The 160m output is reportedly
> substantively less than 4kW. Apparently, you believe that a tank circuit
> which is engineered for 2000 ohms in, 50 ohms out, will also work
> properly for 1000 ohms in, 50 ohms out. I don't.
>
> >Power output was good (about 4 kW) and harmonics were within reason.
> >
> >Are some Alpha's OK, and other's as bad as you say Rich? Or are all
> >the stock tanks the same??
>
> We are not discussing Alphas. We are discussing one model, the Alpha 77.
> Who said all Alpha amplifiers are 'bad'. Different models have
> different problems. The nearly perfect amplifier is apparently not being
> built commercially.
>
> - In your opinion, Mr. Rauch, do you feel that a Centralab 5kv 1000pF
> Series 58 is adequate for the 77's load C 160m padder?
> >
> >Why do you think the tanks Q has to be higher than it is, if
> >harmonics are OK?
> >
> When tank Q falls below a critical amount, the tank is incapable of
> performing the needed Z transformation. As I recall, you pointed this
> out to someone in a previous post on rec......homebrew NG.
> Rich---
>
> R. L. Measures, 805-386-3734, AG6K
>
>
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