01-07-2014, 12:06 PM
Hi All:
I am new to the forum but have been collecting for many years. I am restoring a model 20 catherdral and have a couple questions.
Does anyone know what the DC resistance of the filter choke should be?
On the voltage chart it states the grid voltage on the 71A tubes shoul dbe 50 volts, is this correct? Mine measures 7 volts and the radio works fine but I think it should be more.
Last one, the speaker is in perfect condition but sounds very poor and I would say that is due to the fact the cone has almost no movement, the spider seems to be hard as a rock. Would anyone know if this was a flexable piece 80 or so years ago?
Thanks
Greg
I am new to the forum but have been collecting for many years. I am restoring a model 20 catherdral and have a couple questions.
Does anyone know what the DC resistance of the filter choke should be?
On the voltage chart it states the grid voltage on the 71A tubes shoul dbe 50 volts, is this correct? Mine measures 7 volts and the radio works fine but I think it should be more.
Last one, the speaker is in perfect condition but sounds very poor and I would say that is due to the fact the cone has almost no movement, the spider seems to be hard as a rock. Would anyone know if this was a flexable piece 80 or so years ago?
Thanks
Greg
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