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Model 90B Tinkerer
#4

I suggest you did what I did with mine.

1. Disconnect or replace the AC line filter caps. They are in circuit even with the radio turned off and have a nasty habit of popping.

2. Put all the tubes in except the 80 rectifier and power it up. No need to do it slowly, just go for 117 VAC. All the tubes and dial lamp should light up. You can check the power transformer secondary by stick your AC voltmeter probes into the 80 tube socket. 5 volts across the fat pins. Something like 500-700 across the smaller pins.

3. Replace the two electrolytic caps and apply full power using a dim bulb or similar current limiting device.

I don't really see the point of slowly powering it up unless you're trying to reform the old electrolytics.


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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