[Amps] searching for original 4cx1000 qst project info

[Radio WC6W]

Hi Skipp,
    Perhaps it was a combination of memories?

    The article appeared in CQ Magazine, July 1990, pp. 60-65 but... it
referenced several articles in QST describing the "features"...

   ALC -- QST July 1986 pp. 38,39 47
   Plate meter protection -- QST November 1987, p. 41.
   HV metering -- QST December 1988, p. 43.
   Protection Circuitry -- QST November 1989, pp. 22-25

   That last one listed above may be the one Ralph recollects...

   The author was Mark Mandelkern formerly KN5S, now K5AM e-reachable
via: k5am at zianet.com

73 & Good morning,
   Marv  WC6W 


On Mon, 10 Nov 2003 19:21:20 -0800 skipp isaham <nospam4me at juno.com>
writes:
> Ralph Emailed me looking for a clue and info a QST 
> Amp project using the 4cx1000 as described below. 
> If any of you recognize this project by date/issue and 
> can provide the source info, he and I would appreciate 
> it very much. Post your replies here on amps and I'll 
> forward it back to Ralph. 
> 
> cheers (and thanks)
> skipp 
> nospam4me at juno.com 
> 
> [snip and paste]
> Approximately 20 or more years ago an article appeared 
> in QST about a final amp that used a 4cx1000. It was built 
> by a college professor that taught at New Mexico State in 
> Las cruces. (last name began with an "M" and I never 
> heard it pronounced so I can't remember it). This amp 
> used a 50 ohm passive resistor for the grid circuit and 
> had protection from plate current overload--loss of 
> bias--over and under screen current and over grid current. 
> Best simple system I ever saw. Of course I have lost my 
> copy and desperately need the article (with integral circuit 
> diagram). I have had difficulty constructing a parasitic 
> suppressor that works to my satisfaction so I would like 
> comments on a specific fix for this problem. Any help 
> will be appreciated--all comments listened to. 
> Ralph w5otp.
>