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How to key an older tube amp

813's are way under rated and three of them should be good for nearly a kilowatt. I remember oldtimers talking about drawing an arc off the tank coil with a screwdriver with the key down just because they could. (y)
 
813's are way under rated and three of them should be good for nearly a kilowatt. I remember oldtimers talking about drawing an arc off the tank coil with a screwdriver with the key down just because they could. (y)
the hand writen notes on a 3x5 card said with his Eico radio 100 watts in put out 1500 watts which is illegal and to turn it down to 1000 or what ever was legal. so ya im sure it can do all of 1 kilowatt
 
Well 1500 watts output is the legal limit however I suspect that when that amp was built the regulations specified power INPUT not output. At that time legal limit was 1000 watts DC input which would have been about 600 watts output so 1500 watts input would make about 900-1000 watts out. I forget just how many years ago the regulations changed and a lot of folks do not realize that radios and amps made before that change had the power rated as DC input, which is plate voltage times plate current, and were not rated in power output to the antenna.My Kenwood TS-820S has paperwork stating the power is 200 watts however the output from the pair of 6146B's is a nominal 100 watts. With almost 900 volts and 200mA it has 180 watts DC input however. Close enough.
 
I used to talked to a older fella who used a foot pedal...in qso he would forget to push the pedal and i could not make out what he was saying.....I would remind him he forgot to push the "gas pedal" ha ha
 

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