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Old 11th May 2022, 11:19 pm   #1
AdrianH
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Join Date: Mar 2020
Location: Blackburn with Darwen, Lancashire, UK.
Posts: 1,572
Default Transformer or choke and RC unit

These are starting to intrigue me, in a bits box is an old transformer of unknown make and a Bullphone radio products RC unit.

The transformer has no label on the top as it is missing, but the three terminals from left to right are :-

HT+, C , P&C1. The terminal on the side is labelled Earth.
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Typically around 400 Ohms between HT+ and C and C and P&C1 so 800 Ohms in total, In inductance approx 3.7H per section, but 18H total across HT+ and P&C1. No resistance to Earth, guess it could connect to the laminations or it is open circuit.

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The next unit is basically a holder for glass style resistors, grid leak and I am guessing Plate load resistor. Terminals are HT, P, G and GB, guessing grid bias battery? The caps in the unit are not very well when being read with my TC1 so I assume very leaky. Perhaps I should warm the unit up to remove the wax and see what is in there.

I have several caps in Bakelite cases and guess they will all be duff by now all in wax so should be reasonably easy to replace. I have a couple of 4 pin valve holders and valves etc so thinking of adding a 1920/1930's early battery style project to my list of to do's.

If anyone knows details of the two objects I would appreciate the information.

Adrian
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