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Old 18th Oct 2018, 11:31 am   #131
ms660
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Join Date: Apr 2011
Location: Cornwall, UK.
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Default Re: Aga Baltic AH37. Need help identifying old capacitor from 1930s radio

Quote:
Originally Posted by Mrgroovy View Post
Quote:
Originally Posted by Mike. Watterson View Post
That works. Though don't confuse field coil with humbucking coil, if there is one. It's lower resistance.
So i measured the field coil the right way? Then why is it reading 1.3 Mega Ohm?
If that's the resistance of the field coil then it suggests that the field coil is shot, you can still use the receiver without it by disconnecting the loudspeakers speech coil from the secondary of the output transformer and connecting a low impedance (3 to 8 ohm) loudspeaker in its place, the field coil according to what we've worked out so far is connected across the HT, that means without it you will still have HT present for the receiver to operate, but with the field coil out of circuit the HT would rise above it's design voltage so in order to limit that rise you could connect a resistor in place of the field coil as a substitute load, a 12k 10watt might do the job.

Lawrence.

Last edited by ms660; 18th Oct 2018 at 11:38 am. Reason: clarification
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