Thread: Murphy A104
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Old 31st Dec 2017, 7:34 pm   #18
ms660
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Join Date: Apr 2011
Location: Cornwall, UK.
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Default Re: Murphy A104

I suspect the choke in your receiver is the same as the one used in the radiogram version, that one has a resistance of 265 ohms according to the A104R manual, I have never replaced an HT choke with a resistor but plenty on here have, just remember that the higher the value of the resistor used in place of the choke the lower the HT will be, and the lower the value the greater the ripple voltage will be.

Looking at the A104 and the A104R manuals there's also a difference in the HT winding resistance between the two, the resistances given suggest that the HT voltage at the reservoir would be lower in your receiver than that of the receiver fitted with a field coil loudspeaker.

Lawrence.

Last edited by ms660; 31st Dec 2017 at 7:44 pm.
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