[Amps] Plate Choke Values...

[robert briggs]

Hi all.....Being a very non technical home brewer I mulled over the 
choke problem..I can recall an amplifier I built using a pair of 4-250A 
tubes in GG.....When I first started using it I noticed I was smoking 
the metering resistor to ground at the bottom of the power supply on 160 
meters....I was using a choke formula from God knows where....Anyhow I 
wound up another choke on a 1 inch former with 215 turns and that 
cleared up the problem on 160,80 and 40 meters and that amplifier is 
still being used by a friend after 25 years of operation..

Since then and 40 home brew HF amplifiers later I have used that formula 
for a choke 160 to 20 meters on a fair number of those amplifiers 
usually with an 0047pf choke bypass..

I was restoring an old Yaesu 2100Z amplifier a few years back and I had 
to re wind the plate choke...I carefully unwound the old choke and kept 
the formula and have used that on a number of 1kw output amplifiers 
without any problems....Maybe I was just lucky....

Bob VK3ZL..