Bottlehead Forum

General Category => Technical topics => Topic started by: vetmed on September 02, 2020, 04:57:28 PM

Title: Small signal parafeed transformer
Post by: vetmed 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

Title: Re: Small signal parafeed transformer
Post by: 2wo 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

Title: Re: Small signal parafeed transformer
Post by: Paul Joppa on September 02, 2020, 06:21:38 PM

It gets the signal current out of the cathode bypass capacitor.

Title: Re: Small signal parafeed transformer
Post by: vetmed 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 :)