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Zenith H725
#51

Make that 2 cans fixed. Extracting the discriminator transformer was fiddly, as it's in the corner of the chassis, and there is a tag strip in the way. Then there are several components that have been looped through the tags, and the leads pass on to other tags on the chassis, and tube sockets.

The same clean-up procedure was carried out, along with adding a little silver paint to restore some areas of silvering that were damaged or missing, and hopefully get back to the target capacitances.

Anyway, FM now works much much better, no flutter and crackle or unsteady volume, and I've not even checked FM alignment yet.

Quite the unexpected adventure, but it was definitely SMD in both cases, and if you don't mind the delicate work, these type transformers can be cured. (at least for another 70 years LOL).

I don't hold with furniture that talks.


Messages In This Thread
Zenith H725 - by EdHolland - 03-17-2025, 09:45 PM
RE: Zenith H725 - by MrFixr55 - 03-17-2025, 10:24 PM
RE: Zenith H725 - by EdHolland - 03-18-2025, 11:52 AM
RE: Zenith H725 - by David - 03-18-2025, 01:48 PM
RE: Zenith H725 - by EdHolland - 03-18-2025, 06:09 PM
RE: Zenith H725 - by Arran - 03-18-2025, 10:08 PM
RE: Zenith H725 - by RodB - 03-19-2025, 10:04 AM
RE: Zenith H725 - by EdHolland - 03-19-2025, 10:46 AM
RE: Zenith H725 - by morzh - 03-19-2025, 12:38 PM
RE: Zenith H725 - by RodB - 03-19-2025, 12:55 PM
RE: Zenith H725 - by morzh - 03-19-2025, 01:25 PM
RE: Zenith H725 - by David - 03-19-2025, 03:49 PM
RE: Zenith H725 - by Arran - 03-19-2025, 04:45 PM
RE: Zenith H725 - by Paul Philco322 - 03-19-2025, 08:13 PM
RE: Zenith H725 - by EdHolland - 03-20-2025, 12:34 PM
RE: Zenith H725 - by MrFixr55 - 03-20-2025, 12:59 PM
RE: Zenith H725 - by EdHolland - 03-20-2025, 08:40 PM
RE: Zenith H725 - by MrFixr55 - 03-21-2025, 08:59 AM
RE: Zenith H725 - by radiorich - 03-21-2025, 09:29 AM
RE: Zenith H725 - by EdHolland - 03-21-2025, 09:41 PM
RE: Zenith H725 - by MrFixr55 - 03-21-2025, 09:53 PM
RE: Zenith H725 - by EdHolland - 03-22-2025, 03:17 PM
RE: Zenith H725 - by EdHolland - 03-22-2025, 06:09 PM
RE: Zenith H725 - by RodB - 03-22-2025, 06:52 PM
RE: Zenith H725 - by Arran - 03-22-2025, 07:05 PM
RE: Zenith H725 - by MrFixr55 - 03-22-2025, 08:34 PM
RE: Zenith H725 - by EdHolland - 03-22-2025, 08:40 PM
RE: Zenith H725 - by radiorich - 03-22-2025, 10:22 PM
RE: Zenith H725 - by radiorich - 03-22-2025, 10:35 PM
RE: Zenith H725 - by MrFixr55 - 03-22-2025, 10:39 PM
RE: Zenith H725 - by radiorich - 03-23-2025, 12:17 AM
462ron - by 462ron - 03-23-2025, 08:54 AM
RE: Zenith H725 - by Paul Philco322 - 03-23-2025, 09:18 AM
RE: Zenith H725 - by EdHolland - 03-23-2025, 10:37 AM
RE: Zenith H725 - by radiorich - 03-23-2025, 11:31 AM
462ron - by 462ron - 03-24-2025, 08:22 AM
RE: Zenith H725 - by radiorich - 03-24-2025, 08:34 AM
RE: Zenith H725 - by EdHolland - 03-24-2025, 02:44 PM
RE: Zenith H725 - by EdHolland - 03-24-2025, 06:56 PM
RE: Zenith H725 - by radiorich - 03-24-2025, 10:33 PM
RE: Zenith H725 - by EdHolland - 03-24-2025, 10:46 PM
RE: Zenith H725 - by Arran - 03-24-2025, 11:42 PM
RE: Zenith H725 - by EdHolland - 03-25-2025, 11:49 AM
RE: Zenith H725 - by Arran - 03-25-2025, 06:40 PM
RE: Zenith H725 - by EdHolland - 03-25-2025, 06:42 PM
RE: Zenith H725 - by EdHolland - 03-25-2025, 09:13 PM
RE: Zenith H725 - by radiorich - 03-26-2025, 01:02 AM
RE: Zenith H725 - by EdHolland - 03-27-2025, 10:57 AM
RE: Zenith H725 - by EdHolland - 03-27-2025, 04:25 PM
RE: Zenith H725 - by EdHolland - 03-27-2025, 11:08 PM
RE: Zenith H725 - by EdHolland - 03-28-2025, 03:45 PM
RE: Zenith H725 - by EdHolland - 03-28-2025, 09:53 PM
RE: Zenith H725 - by radiorich - 03-29-2025, 01:27 AM
RE: Zenith H725 - by MrFixr55 - 03-29-2025, 02:33 PM
RE: Zenith H725 - by David - 03-29-2025, 06:28 PM



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