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Zenith 12H090
#35

Funny how things don't look tricky until you start work. I got all but one of the paper caps changed on the RF chassis today, but it was more fiddly than expected. That last cap shouldn't be a problem, but I ran out of time.

At one point, working around an IF transformer, I was concerned about internal connections.... One of the paper caps was fitted so that the lead passed through two terminals on the transformer. One of these terminals had no continuity. This prompted me to the lengthy detour of removing the transformer, and opening it up. Of course, that leg showed that it had never had a connection in the first place. Back it all went.

Thinking now about simulating the "Wave Magnet". From the schematic, it is clear that it has a center tap, grounded, such that the feed to the receiver is balanced. I also need to configure an output transformer and speaker for audio testing.

Cheers

Ed

I don't hold with furniture that talks.


Messages In This Thread
Zenith 12H090 - by EdHolland - 05-27-2018, 03:11 AM
RE: Zenith 12H090 - by morzh - 05-27-2018, 11:30 AM
RE: Zenith 12H090 - by EdHolland - 05-27-2018, 07:54 PM
RE: Zenith 12H090 - by morzh - 05-27-2018, 11:14 PM
RE: Zenith 12H090 - by EdHolland - 05-29-2018, 01:51 PM
RE: Zenith 12H090 - by Electrothaumaturgist - 05-30-2018, 02:26 PM
RE: Zenith 12H090 - by morzh - 05-30-2018, 04:51 PM
RE: Zenith 12H090 - by Electrothaumaturgist - 05-30-2018, 06:26 PM
RE: Zenith 12H090 - by Arran - 05-31-2018, 04:42 AM
RE: Zenith 12H090 - by EdHolland - 05-31-2018, 04:08 PM
RE: Zenith 12H090 - by Electrothaumaturgist - 06-01-2018, 01:41 AM
RE: Zenith 12H090 - by Arran - 06-01-2018, 02:15 AM
RE: Zenith 12H090 - by Electrothaumaturgist - 06-01-2018, 03:39 AM
RE: Zenith 12H090 - by morzh - 06-01-2018, 07:55 AM
RE: Zenith 12H090 - by EdHolland - 06-01-2018, 12:43 PM
RE: Zenith 12H090 - by Electrothaumaturgist - 06-01-2018, 03:31 PM
RE: Zenith 12H090 - by Arran - 06-02-2018, 03:06 AM
RE: Zenith 12H090 - by Electrothaumaturgist - 06-02-2018, 05:48 AM
RE: Zenith 12H090 - by EdHolland - 10-25-2018, 11:51 PM
RE: Zenith 12H090 - by Arran - 10-27-2018, 04:09 PM
RE: Zenith 12H090 - by jcassity - 10-28-2018, 07:57 PM
RE: Zenith 12H090 - by EdHolland - 12-02-2018, 12:44 PM
RE: Zenith 12H090 - by EdHolland - 12-03-2018, 03:03 AM
RE: Zenith 12H090 - by EdHolland - 12-05-2018, 03:00 PM
RE: Zenith 12H090 - by EdHolland - 12-09-2018, 09:58 PM
RE: Zenith 12H090 - by Ron Ramirez - 12-09-2018, 11:17 PM
RE: Zenith 12H090 - by Arran - 12-10-2018, 05:34 AM
RE: Zenith 12H090 - by morzh - 12-10-2018, 09:20 AM
RE: Zenith 12H090 - by EdHolland - 12-11-2018, 02:05 PM
RE: Zenith 12H090 - by EdHolland - 12-16-2018, 11:45 PM
RE: Zenith 12H090 - by EdHolland - 01-13-2019, 09:37 PM
RE: Zenith 12H090 - by EdHolland - 01-20-2019, 11:20 PM
RE: Zenith 12H090 - by EdHolland - 01-27-2019, 10:35 PM
RE: Zenith 12H090 - by EdHolland - 02-01-2019, 05:06 PM
RE: Zenith 12H090 - by EdHolland - 02-02-2019, 10:26 PM
RE: Zenith 12H090 - by jcassity - 02-03-2019, 01:47 PM
RE: Zenith 12H090 - by EdHolland - 02-03-2019, 05:56 PM
RE: Zenith 12H090 - by EdHolland - 02-03-2019, 07:34 PM
RE: Zenith 12H090 - by jcassity - 02-04-2019, 11:55 AM
RE: Zenith 12H090 - by EdHolland - 02-04-2019, 03:29 PM
RE: Zenith 12H090 - by EdHolland - 02-08-2019, 02:37 PM
RE: Zenith 12H090 - by EdHolland - 02-09-2019, 11:17 PM
RE: Zenith 12H090 - by morzh - 02-10-2019, 11:19 AM
RE: Zenith 12H090 - by EdHolland - 02-11-2019, 04:04 PM
RE: Zenith 12H090 - by EdHolland - 02-12-2019, 01:27 PM
RE: Zenith 12H090 - by EdHolland - 02-18-2019, 02:36 PM
RE: Zenith 12H090 - by EdHolland - 02-23-2019, 03:17 AM
RE: Zenith 12H090 - by OldRestorer - 02-23-2019, 08:14 AM
RE: Zenith 12H090 - by EdHolland - 02-23-2019, 07:17 PM
RE: Zenith 12H090 - by EdHolland - 02-23-2019, 07:34 PM
RE: Zenith 12H090 - by EdHolland - 02-23-2019, 09:10 PM
RE: Zenith 12H090 - by OldRestorer - 02-24-2019, 03:02 PM
RE: Zenith 12H090 - by EdHolland - 02-25-2019, 06:34 PM
RE: Zenith 12H090 - by jcassity - 02-25-2019, 07:31 PM
RE: Zenith 12H090 - by tbone - 02-25-2019, 08:31 PM
RE: Zenith 12H090 - by Arran - 02-26-2019, 06:55 AM
RE: Zenith 12H090 - by EdHolland - 02-26-2019, 09:15 PM
RE: Zenith 12H090 - by OldRestorer - 03-19-2019, 01:01 PM
RE: Zenith 12H090 - by EdHolland - 03-19-2019, 09:36 PM
RE: Zenith 12H090 - by EdHolland - 05-26-2019, 12:46 AM
RE: Zenith 12H090 - by morzh - 05-26-2019, 08:32 AM
RE: Zenith 12H090 - by EdHolland - 05-26-2019, 10:48 AM
RE: Zenith 12H090 - by Eliot Ness - 05-26-2019, 11:11 AM
RE: Zenith 12H090 - by EdHolland - 05-26-2019, 09:22 PM
RE: Zenith 12H090 - by morzh - 05-27-2019, 10:43 AM
RE: Zenith 12H090 - by EdHolland - 05-27-2019, 11:48 AM
RE: Zenith 12H090 - by EdHolland - 01-12-2021, 08:45 PM
RE: Zenith 12H090 - by Arran - 01-13-2021, 12:31 AM
RE: Zenith 12H090 - by EdHolland - 01-13-2021, 11:33 AM
RE: Zenith 12H090 - by EdHolland - 01-16-2021, 09:58 PM
RE: Zenith 12H090 - by EdHolland - 01-21-2021, 08:25 PM



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