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Noise in the a/c line
#16

Using coaxial cable on the input to most 1930's radios, especially Philco's, isn't a good idea unless you use a ferrite balun transformer at the antenna terminals; even using a balun will have mixed results. If you look at the input schematic you will see that the capacitance of the coax will go directly across the input input tuning stages; all of this added capacitance will kill reception. You will find that you won't be able to adjust the input stages when using coax.

A hand-wound 1:1 balun of a few turns might reduce background noise but at the cost of some sensitivity.

Pete AI2V


Messages In This Thread
Noise in the a/c line - by Robert - 11-26-2008, 11:52 PM
Re: Noise in the a/c line - by rghines1 - 11-27-2008, 11:04 AM
Re: Noise in the a/c line - by Robert - 11-27-2008, 11:56 AM
Re: Noise in the a/c line - by rghines1 - 11-27-2008, 05:41 PM
Re: Noise in the a/c line - by radiomikee - 11-28-2008, 09:39 AM
Re: Noise in the a/c line - by Robert - 11-28-2008, 07:55 PM
Re: Noise in the a/c line - by exray - 11-28-2008, 08:11 PM
Re: Noise in the a/c line - by Robert - 11-29-2008, 09:32 AM
Re: Noise in the a/c line - by exray - 11-29-2008, 09:41 AM
Re: Noise in the a/c line - by Robert - 11-29-2008, 09:53 AM
Re: Noise in the a/c line - by radiomikee - 12-04-2008, 01:37 PM
Re: Noise in the a/c line - by radiomikee - 12-04-2008, 01:44 PM
Re: Noise in the a/c line - by DeckApe - 12-04-2008, 02:35 PM
Re: Noise in the a/c line - by Texasrocker - 12-07-2008, 01:37 AM
Re: Noise in the a/c line - by DeckApe - 12-07-2008, 12:03 PM
Re: Noise in the a/c line- COAXIAL NO-NO - by AI2V - 12-07-2008, 12:22 PM
Re: Noise in the a/c line - by codefox1 - 12-12-2008, 11:15 AM
Re: Noise in the a/c line - by Robert - 12-13-2008, 11:06 AM
Re: Noise in the a/c line - by radiomikee - 12-15-2008, 02:01 PM
Re: Noise in the a/c line - by exray - 12-16-2008, 10:24 AM



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