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Restoring Philco 38-14
#19

Mr. Fixr

Yes, about the rectifier. Though the noise, when them plug is polarized (I have just changed it) and plugged consistently with the negative of the sch (the switch) to the Neutral, is fairly low.

Transformer is indeed a low-pass filter, when it comes to the differential; with the common mode (everything differential of Hi-Frequency will create a CM at the output via the inter-winding capacitance) it is a good question if we care enough about it, as in today's devices the sole reason we do is the compliance (hence the bridge cap), and the two Y-caps at the primary winding to the chassis will take care of it, even though we cannot hear it much.
Yes, the same Hi-F input will create some of the differential output, but like you said, the transformer itself will attenuate it, plus the rectifier filter (and in theory a smaller low inductance cap in parallel to the electrolytics should help further) will kill the rest of it.

Good thing is, the second rectifier capacitane (in the LC filter) is not really limited (within reason), so the cap could be increase almost indefinitely (within reason).

In fact, I implemented a Greinacher doubler in my Telefunken (to make DC close to the one made of 220VAC), and that radio is fairly quiet.


-----------------------



Now, about the cabinet.
Whatever happened to GoJo? None of our two auto stores (Advanced A/P and Autozone; the PepBoys stopped being a store and retained only service facility) carries it anymore; they carry that orange stuff, with pumice and the one without the pumice has aloe and some other cosmetic stuff I don't care about.
I will have to order Goop or GoJo in smaller tubs online; Amazon does not even carry GoJo, only Goop.

Oh well. Seems like my hook and pick kit came.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Restoring Philco 38-14 - by morzh - 09-09-2024, 07:04 PM
RE: Restoring Philco 38-14 - by morzh - 09-14-2024, 04:49 PM
RE: Restoring Philco 38-14 - by morzh - 09-15-2024, 09:30 PM
RE: Restoring Philco 38-14 - by morzh - 09-28-2024, 07:40 PM
RE: Restoring Philco 38-14 - by morzh - 09-28-2024, 09:35 PM
RE: Restoring Philco 38-14 - by morzh - 09-29-2024, 09:04 PM
RE: Restoring Philco 38-14 - by morzh - 09-30-2024, 10:23 PM
RE: Restoring Philco 38-14 - by radiorich - 10-01-2024, 12:25 AM
RE: Restoring Philco 38-14 - by morzh - 10-01-2024, 08:07 AM
RE: Restoring Philco 38-14 - by radiorich - 10-01-2024, 08:45 AM
RE: Restoring Philco 38-14 - by RodB - 10-01-2024, 10:01 AM
RE: Restoring Philco 38-14 - by morzh - 10-01-2024, 11:11 AM
RE: Restoring Philco 38-14 - by morzh - 10-01-2024, 09:15 PM
RE: Restoring Philco 38-14 - by radiorich - 10-02-2024, 09:43 AM
RE: Restoring Philco 38-14 - by morzh - 10-04-2024, 09:42 PM
RE: Restoring Philco 38-14 - by radiorich - 10-05-2024, 12:42 AM
RE: Restoring Philco 38-14 - by RadioSvit - 10-05-2024, 02:55 AM
RE: Restoring Philco 38-14 - by MrFixr55 - 10-05-2024, 08:13 AM
RE: Restoring Philco 38-14 - by morzh - 10-05-2024, 02:01 PM
RE: Restoring Philco 38-14 - by morzh - 10-05-2024, 08:52 PM
RE: Restoring Philco 38-14 - by morzh - 10-05-2024, 08:55 PM
RE: Restoring Philco 38-14 - by radiorich - 10-05-2024, 09:28 PM
RE: Restoring Philco 38-14 - by morzh - 10-05-2024, 09:57 PM
RE: Restoring Philco 38-14 - by radiorich - 10-06-2024, 03:38 PM
RE: Restoring Philco 38-14 - by morzh - 10-06-2024, 10:15 PM
RE: Restoring Philco 38-14 - by radiorich - 10-06-2024, 10:33 PM
RE: Restoring Philco 38-14 - by morzh - 10-07-2024, 08:56 AM
RE: Restoring Philco 38-14 - by morzh - 10-07-2024, 07:48 PM
RE: Restoring Philco 38-14 - by Paul Philco322 - 10-07-2024, 09:20 PM
RE: Restoring Philco 38-14 - by morzh - 10-07-2024, 09:25 PM
RE: Restoring Philco 38-14 - by morzh - 10-07-2024, 09:28 PM
RE: Restoring Philco 38-14 - by MrFixr55 - 10-07-2024, 10:57 PM
RE: Restoring Philco 38-14 - by Arran - 10-08-2024, 12:28 AM
RE: Restoring Philco 38-14 - by morzh - 10-08-2024, 08:54 AM
RE: Restoring Philco 38-14 - by RadioSvit - 10-08-2024, 01:52 PM
RE: Restoring Philco 38-14 - by morzh - 10-08-2024, 04:02 PM
RE: Restoring Philco 38-14 - by Paul Philco322 - 10-08-2024, 07:52 PM
RE: Restoring Philco 38-14 - by radiorich - 10-09-2024, 01:25 AM
RE: Restoring Philco 38-14 - by morzh - 10-09-2024, 08:22 AM
RE: Restoring Philco 38-14 - by RodB - 10-09-2024, 12:09 PM
RE: Restoring Philco 38-14 - by morzh - 10-09-2024, 01:14 PM
RE: Restoring Philco 38-14 - by MrFixr55 - 10-09-2024, 09:11 PM
RE: Restoring Philco 38-14 - by morzh - 10-09-2024, 10:49 PM



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