In article ,
John Rumm wrote:
Or perhaps the original relay damage was caused by failure of the
choke that isolated the element's power supply from its aerial
function, so now when powered, you are in effect grounding your
aerial as well?

A capacitor will also be needed to isolate any DC from the aerial
input.

Yup, although there is a fair chance the radio will have that internally.

The installations I've seen that use the rear screen as an aerial have an
amp mounted close to it - which I assume removes all the nasties before
sending it off to the head unit.

--
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Dave Plowman London SW
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