Amps
[Top] [All Lists]

[AMPS] iron needed

To: <amps@contesting.com>
Subject: [AMPS] iron needed
From: 2@vc.net (2)
Date: Fri, 29 Jun 2001 09:30:26 -0700
>
>I already put this on the AM lists, but I got no bites. Maybe some 
>amplifier builder has a stash of ancient iron....
>
>I need a 500 Watt modulation transformer for a homebrew project. It 
>should have roughly 16 k Ohm plate to plate Z for the audio side and 
>about 6-7 k Ohms for the RF side with 1/2 Amp DC through it there.
>
>Stancor, UTC, Thordarson, SNC, all made universal transformers 50 
>years ago, and I have plenty of ancient part numbers to pursue. But 
>who has this old iron laying in their junkbox?
>
>If you have something that looks like audio transformer, and its 
>about 50-70 lbs, please let me know and I will check the number 
>versus my 1952 catalogs.
>
/\  Peter Dahl can build one.  A caveat -- The old modulation xfmr Z 
formula is in error because it does not compensate for the (50%) negative 
R region of modulation.  A closer match can be had by analyzing  +peak 
currents and +peak voltages.  Congrats to Eimac's Mr. John Reinartz  
(RIP) for his slam-dunk essay on plate (anode) modulation analysis.  
>
cheers, John


-  R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.  
end


--
FAQ on WWW:               http://www.contesting.com/FAQ/amps
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com


<Prev in Thread] Current Thread [Next in Thread>