[AMPS] Alpha 77 amps

[Peter Gerba]

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>
> >> 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   
> 
> 
> --
> FAQ on WWW:               http://www.contesting.com/ampfaq.html
> Submissions:              amps@contesting.com
> Administrative requests:  amps-REQUEST@contesting.com
> Problems:                 owner-amps@contesting.com
> Search:                   http://www.contesting.com/km9p/search.htm
> 

--
FAQ on WWW:               http://www.contesting.com/ampfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm