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Jerry G. Jerry G. is offline
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Default Car radio antenna has an inline .85mfd capacitor, why?

On the windscreen, in the winter dry snow will be brushing against the
windscreen, and in the summer during a rain storm the windscreen can
act in a way they could build up some DC static type voltages. The
cap will block this effect. The cap basicaly acts as a protection
against any DC from going in to the radio's front end.


Jerry G.


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On Sep 28, 8:13 pm, Bill Freeman wrote:
I have an 87 Nissan van with an antenna wire that has a 0.85 mfd
capacitor soldered between the center wire and the center pin of the
antenna connector, on the end that plugs into the radio.

This vehicle actually has two antenna wires that connect side by side
at the radio. One antenna is printed onto the centerline of the
windshield, and the other is a conventional whip antenna mounted at the
drivers side of the roof. The roof antenna lead is the one with the
capacitor.

Anyone know what the purpose of an inline capacitor would be on a car
radio?

Another car antenna question, why do they use such a small diameter
wire inside the coax? The wire inside this coax is about .010 inches
in diameter. Is it this small to save on copper, or is there some
technical advantage to a small diameter wire.

--
Bill Freeman