[Top] [All Lists]

[Amps] SCR to adjust 240v to 200v

To: <>
Subject: [Amps] SCR to adjust 240v to 200v
From: "Jim Thomson" <>
Date: Mon, 15 Aug 2016 07:42:24 -0700
List-post: <">>
Date: Sat, 13 Aug 2016 11:11:33 -0400
From: Jim Durham <>
Subject: Re: [Amps] SCR to adjust 240v to 200v

Thank you, Boye (OZ7C) and the others that replied.  I think I did not 
explain my project clearly.

First of all, yes, I know about buck transformers.  I am using a Variac, 
which does the same thing and also allows me to adjust the input AC 
voltage. The Henry 2K has the filament voltage supplied from a winding 
on the plate transformer, so, with the Variac, I can adjust the input AC 
voltage to give about 9.8 volts for the filaments, which is ideal and 
produces 3000 volts for the plates.

A large buck transformer or Variac requires an external box, which is 
what I am using now. They won't fit in the amplifier without seriously 
hacking up the cabinet.  I don't want to do that.

So, I was just asking if anyone on Amps had tried using an SCR to 
control a large choke-input power supply ?   That sounds attractive and 
would fit in the cabinet,  but also might damage the power supply choke 
by applying non-sinusoidal power (the 2K-2 has a choke input power 
supply).  That was my question.

Thanks to all,  I should have explained more clearly what I was asking.

73 de Jim, W2XO

##  still another method is to use a small variac on the primary of the buck 
Sec of buck xfmr goes in series with one leg of the 240 line.   Then u can 
dial up the exact buck voltage you want.  Forget the scr, not gonna work. 
Or use a buck xfmr with several taps on both the pri and sec.

Jim  VE7RF

Amps mailing list

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