UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Philco a-535b mark iii

Simon Gittins · 23rd Mar 2023, 10:15 am

The Manufacturer's service data is here:
https://www.service-data.com/product...74/5548/m14274
It's 26 pages. At the top it says it for the Mk I and Mk II but at the end of the document is provisional information for the Mk III (confirming the speaker is the energised type).
I suggest as a first step resistance checks (power off of course) for the field coil which should be about 1140 ohms and the output transformer primary which should be about 450 ohms.
These can both fail open circuit due to faulty capacitors so if they measure ok now you will need to take steps to ensure they stay that way but one step at a time.

23rd Mar 2023, 10:15 am	#22
Simon Gittins Heptode Join Date: Jan 2006 Location: Cornwall, UK. Posts: 506	Re: Philco a-535b mark iii The Manufacturer's service data is here: https://www.service-data.com/product...74/5548/m14274 It's 26 pages. At the top it says it for the Mk I and Mk II but at the end of the document is provisional information for the Mk III (confirming the speaker is the energised type). I suggest as a first step resistance checks (power off of course) for the field coil which should be about 1140 ohms and the output transformer primary which should be about 450 ohms. These can both fail open circuit due to faulty capacitors so if they measure ok now you will need to take steps to ensure they stay that way but one step at a time.