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September 30, 2020, 06:42:10 PM

Author Topic: Small signal parafeed transformer  (Read 99 times)

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Offline vetmed

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Small signal parafeed transformer
« on: September 02, 2020, 04:57:28 PM »
What if any would be the virtue of taking the ground  return lead to the top of cathode resistor? I'm looking at something I built more than 20 years ago and wondering why I did it ::) It works but then I was just following a schematic with little real understanding of what I was doing :o Hopefully I have made myself understood and appreciate any input.
Regards
Robert Lees
Robert Lees

Offline 2wo

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Re: Small signal parafeed transformer
« Reply #1 on: September 02, 2020, 05:16:33 PM »
Have a look at the "Valve" archives there were a few articles on parafeed theory, if I recall correctly there was one on the four ways to connect and the pluses and minuses of each...John
John Scanlon

Offline Paul Joppa

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Re: Small signal parafeed transformer
« Reply #2 on: September 02, 2020, 06:21:38 PM »
It gets the signal current out of the cathode bypass capacitor.
Paul Joppa

Offline vetmed

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Re: Small signal parafeed transformer
« Reply #3 on: September 03, 2020, 05:34:20 AM »
Thanks, I found one article in valve magazine entitled 12 Ways to parafeed.  It showed the 12 ways but offered little explanation, so your response save a lot of searching :)
Robert Lees