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Philco 71 restoration
#28

An osc is a amp with a small amount the output fed back to the input. Among homebrewers it all ways seems when building something that is suppose to oscillate it amplifies and vise versa.
How your set does it is a bit of the energy from the cathode is coupled inductively to the plate though the coil. With the cathode coil open two things happen. One no feedback/no oscillation. Two the 36 tube has no dc ground so it won't draw much it any current. So it won't amplify very well either.
Make sense?
Terry 'gte
PS
Short answer is yes.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


Messages In This Thread
Philco 71 restoration - by ipwizard - 09-29-2011, 12:48 AM
RE: Philco 71 restoration - by ipwizard - 03-02-2012, 06:09 PM
Re: Man this thing is a nightmare - by ipwizard - 09-29-2011, 01:36 AM
Re: Man this thing is a nightmare - by ipwizard - 09-29-2011, 10:14 PM
Re: Man this thing is a nightmare - by ipwizard - 10-06-2011, 12:29 AM
Re: Man this thing is a nightmare - by Arran - 10-06-2011, 02:24 AM
Re: Man this thing is a nightmare - by rghines1 - 10-06-2011, 10:20 AM
Re: Man this thing is a nightmare - by exray - 10-06-2011, 12:41 PM
Re: Man this thing is a nightmare - by ipwizard - 10-08-2011, 10:34 PM
Re: Man this thing is a nightmare - by Marsupial - 10-08-2011, 11:52 PM
Re: Man this thing is a nightmare - by exray - 10-09-2011, 05:56 AM
Re: Man this thing is a nightmare - by ipwizard - 10-10-2011, 01:40 PM
Re: Philco 71 restoration - by ipwizard - 10-31-2011, 05:10 PM
Re: Philco 71 restoration - by 7estatdef - 10-31-2011, 08:48 PM
Re: Philco 71 restoration - by 7estatdef - 10-31-2011, 09:00 PM
Re: Philco 71 restoration - by ipwizard - 11-01-2011, 01:03 AM
Re: Philco 71 restoration - by ipwizard - 11-01-2011, 01:06 AM
Re: Philco 71 restoration - by 7estatdef - 11-01-2011, 10:58 PM
Re: Philco 71 restoration - by ipwizard - 11-03-2011, 01:03 AM
Re: Philco 71 restoration - by 7estatdef - 11-03-2011, 02:59 AM
Re: Philco 71 restoration - by codefox1 - 11-03-2011, 10:04 AM
Re: Philco 71 restoration - by ipwizard - 11-03-2011, 06:00 PM
Re: Philco 71 restoration - by 7estatdef - 11-03-2011, 06:26 PM
Re: Philco 71 restoration - by ipwizard - 11-03-2011, 06:31 PM
Re: Philco 71 restoration - by 7estatdef - 11-03-2011, 06:42 PM
Re: Philco 71 restoration - by ipwizard - 11-03-2011, 07:40 PM
Re: Philco 71 restoration - by 7estatdef - 11-03-2011, 08:39 PM
Re: Philco 71 restoration - by ipwizard - 11-03-2011, 09:38 PM
Re: Philco 71 restoration - by ipwizard - 11-04-2011, 12:29 AM
Re: Philco 71 restoration - by ipwizard - 11-04-2011, 02:33 PM
Re: Philco 71 restoration - by ipwizard - 11-30-2011, 11:56 PM
Re: Philco 71 restoration - by TA Forbes - 12-01-2011, 12:37 AM
Re: Philco 71 restoration - by TA Forbes - 12-02-2011, 09:54 PM
Re: Philco 71 restoration - by codefox1 - 12-03-2011, 11:48 AM
Re: Philco 71 restoration - by ipwizard - 12-04-2011, 03:03 PM
Re: Philco 71 restoration - by ipwizard - 12-23-2011, 04:36 AM



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