[AMRadio] Mod Transformer Available (message clarified)

Donald Chester k4kyv at hotmail.com
Wed Sep 28 17:21:52 EDT 2005

Let me resend the message in case anyone couldn't figure it out.  Evidently 
the software that runs this message board doesn't recognise the "ohms" 
symbol omega.

>>The ratings are 5500 primary 1.14 KVA, and 5500 secondary
>>198 Amp DC.


>I don't know what you mean by don't add up! The discussion
>was pertaining to the use of this particular transformer, in
>conjunction with a specific set of tubes, and RF stage.

>What doesn't add up?

The tagged ratings of the transformer.  1.14 kva means it is rated for about 
a kw of audio (theoretically 1140 watts with perfect power factor)  just 
call it a kw to account for some inevitable phase shift.  That means it 
should be designed to modulate 2 kw DC input.  But with the maximum current 
rating of .198 amps, to get 2 kw DC input, you would need 10,101 volts on 
the plate.  The rated load impedance is 5500 ohms.  10 kv @ 198 mills is 
51,152 ohms.

There is no way you can run the transformer at maximum rated DC secondary 
current, at maximum rated  power level, and maintain the nominal load 
impedance of 5500 ohms.


More information about the AMRadio mailing list

This page last updated 24 Feb 2018.