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Model 90B Tinkerer
#1

I've been following Bob Andersons trials and tribulations on his 90, but this one in pretty good shape overall.  Like his, this has a single 47 output tube.

What's missing:
-the Large tube shield (with tube layout sticker)
-another shield on the other side (there's a clip there)
-one of the original filter capacitors
-no stickers!

Other:
-strange shape of the volume control shaft, makes the knob wobble. Don't want no wobbling knobs!
-strange red grounding wire on the choke housing to the chassis
-deformed tuning dial

Tubes all test good (2 may be original). I use an old Signal Corps I-177 tester.
The tubes all light up with the rectifier removed.

Transformers, including PT, speaker, output transformer, and choke all seem to be good except for the RF 1st Det. coil (7), open primary.  What a surprise.

BTW, I've found that a dab of WD-40 on the grid caps and tube pin sockets make them suckers jump right out of there! I use a q-tip. Also grip tubes by the base, not the envelope.
And, now for your viewing pleasure:
   
   
   
Notice the shape of the volume control shaft
   
   
Big red ugly wire grounding the case which is insulated from the chassis (?!)
   
All that green stuff is fragmented wire.
   
91 turns required (don't laugh at my winder! it works)  That's 3m electrical tape sticky side out, one layer.
   
That's all folks (until round 2)


Messages In This Thread
Model 90B Tinkerer - by Simon Wa3uay - 11-17-2021, 02:58 PM
RE: Model 90B Tinkerer - by Bob Andersen - 11-17-2021, 10:25 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 11-18-2021, 01:43 PM
RE: Model 90B Tinkerer - by Bob Andersen - 11-18-2021, 06:12 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 11-19-2021, 04:07 PM
RE: Model 90B Tinkerer - by radiorich - 11-20-2021, 12:50 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 11-20-2021, 01:31 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 11-24-2021, 04:11 PM
RE: Model 90B Tinkerer - by morzh - 11-24-2021, 05:02 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 11-25-2021, 09:58 AM
RE: Model 90B Tinkerer - by cknob - 11-25-2021, 10:43 AM
RE: Model 90B Tinkerer - by Simon Wa3uay - 11-25-2021, 10:58 AM
RE: Model 90B Tinkerer - by cknob - 11-25-2021, 01:25 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 11-27-2021, 09:40 AM
RE: Model 90B Tinkerer - by morzh - 11-27-2021, 02:48 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 01-14-2022, 01:18 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 01-16-2022, 11:37 AM
RE: Model 90B Tinkerer - by Mondial - 01-16-2022, 01:22 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 01-21-2022, 11:25 AM
RE: Model 90B Tinkerer - by Mondial - 01-21-2022, 11:39 AM
RE: Model 90B Tinkerer - by Simon Wa3uay - 01-21-2022, 04:06 PM
RE: Model 90B Tinkerer - by klondike98 - 01-22-2022, 01:26 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 01-22-2022, 02:35 PM
RE: Model 90B Tinkerer - by Ron Ramirez - 01-22-2022, 02:58 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 01-23-2022, 11:32 AM
RE: Model 90B Tinkerer - by Simon Wa3uay - 01-26-2022, 09:09 AM
RE: Model 90B Tinkerer - by Mondial - 01-26-2022, 11:38 AM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-01-2022, 01:39 PM
RE: Model 90B Tinkerer - by Mondial - 02-01-2022, 02:12 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-01-2022, 02:23 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-01-2022, 03:09 PM
RE: Model 90B Tinkerer - by Mondial - 02-01-2022, 09:31 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-09-2022, 02:32 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-09-2022, 02:39 PM
RE: Model 90B Tinkerer - by Bob Andersen - 02-09-2022, 02:48 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-09-2022, 02:53 PM
RE: Model 90B Tinkerer - by GarySP - 02-09-2022, 02:57 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-09-2022, 03:13 PM
RE: Model 90B Tinkerer - by Mondial - 02-09-2022, 03:36 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-09-2022, 03:41 PM
RE: Model 90B Tinkerer - by Steve Davis - 02-09-2022, 04:20 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-09-2022, 04:33 PM
RE: Model 90B Tinkerer - by Steve Davis - 02-09-2022, 05:40 PM
RE: Model 90B Tinkerer - by Ron Ramirez - 02-09-2022, 08:51 PM
RE: Model 90B Tinkerer - by Simon Wa3uay - 02-11-2022, 08:08 AM
RE: Model 90B Tinkerer - by Simon Wa3uay - 08-06-2022, 03:40 PM



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