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Heathkit GD-1B
#16

Hmmm, Yes I thought of that. 
I've been trying to just check the circuit at this point without letting out any magic smoke.
I have taken the line voltage up to 80 VAC which gives 96 or so on pin1.
These measurements are static as I removed the tube.
The other leg of the 95 VDC supply shows a reading of 10 VDC or so, so those resistors have an effect on the voltage.
I just now went back and re-measured with the tube installed.
I took it up to maybe 75 VDC, nothing.
I tried 80 VAC on the line again, and THIS time voltage on pin 1 went to 96 VDC, then began dropping after a moment.
Thanks!
It finally stabilized with 40 VDC on pin 1, -1 V on pin 2, 101 V on the supply.
Anyway, great breakthrough for me! Thanks so much!
I still don't know why I cant get more -V on the grid, the -1 VDC was obtained with the 37-100 mHz coil and the air cap all the way open.
Cleaning the old socket connections may help with that.

Again, thanks for your great advice!
                                                       Robert


Messages In This Thread
Heathkit GD-1B - by vecher - 12-31-2018, 06:37 PM
RE: Heathkit GD-1B - by gregb - 12-31-2018, 06:44 PM
RE: Heathkit GD-1B - by Radioroslyn - 12-31-2018, 06:58 PM
RE: Heathkit GD-1B - by vecher - 12-31-2018, 06:59 PM
RE: Heathkit GD-1B - by vecher - 12-31-2018, 07:02 PM
RE: Heathkit GD-1B - by Steve Davis - 12-31-2018, 07:56 PM
RE: Heathkit GD-1B - by Steve Davis - 12-31-2018, 07:57 PM
RE: Heathkit GD-1B - by Radioroslyn - 12-31-2018, 08:03 PM
RE: Heathkit GD-1B - by vecher - 01-01-2019, 10:09 PM
RE: Heathkit GD-1B - by Chas - 01-01-2019, 11:17 PM
RE: Heathkit GD-1B - by vecher - 01-02-2019, 12:11 AM
RE: Heathkit GD-1B - by Radioroslyn - 01-03-2019, 11:28 AM
RE: Heathkit GD-1B - by vecher - 01-09-2019, 01:46 AM
RE: Heathkit GD-1B - by Surfur - 01-17-2019, 01:46 AM
RE: Heathkit GD-1B - by Radioroslyn - 01-17-2019, 10:52 AM
RE: Heathkit GD-1B - by Surfur - 01-17-2019, 01:24 PM
RE: Heathkit GD-1B - by vecher - 01-19-2019, 12:14 AM
RE: Heathkit GD-1B - by vecher - 01-19-2019, 09:39 PM
RE: Heathkit GD-1B - by Surfur - 01-20-2019, 02:58 AM
RE: Heathkit GD-1B - by vecher - 01-20-2019, 11:10 AM
RE: Heathkit GD-1B - by vecher - 01-20-2019, 04:56 PM
RE: Heathkit GD-1B - by KCMike - 01-20-2019, 05:53 PM
RE: Heathkit GD-1B - by vecher - 01-20-2019, 08:29 PM
RE: Heathkit GD-1B - by vecher - 01-21-2019, 12:04 AM
RE: Heathkit GD-1B - by vecher - 02-15-2019, 09:17 PM
RE: Heathkit GD-1B - by EdHolland - 02-15-2019, 09:39 PM
RE: Heathkit GD-1B - by Surfur - 03-12-2019, 10:12 PM
RE: Heathkit GD-1B - by EdHolland - 03-12-2019, 11:57 PM
RE: Heathkit GD-1B - by vecher - 03-13-2019, 03:00 PM



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