For the PTT you can use single core shielded wire using the shielding as the
earth connection at both ends
For the headsets use 3 core shielded as you say, mic, audio and earth but
make sure you earth the shielding as well on the radio end only, just cut it
off at the headset end and leave it, if you earth the shielding at both ends
it creates its own circuit and you will have interference
Gavin...#355... ZK-EPA
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of William Daniell
Sent: Tuesday, 13 September 2011 5:50 a.m.
Subject: Europa-List: Radio wiring
A question for the assembled wisdom...do the PTT wires need to be shielded?
As I understand it the standard is a 3 core shielded wire for each headset
. Audio: white cores and shield/earth
. Mic: 2 cores (red and blue)and earth/shield . Until you
energize the mic by earthing it, it is "off". In order to activate the mic
you "energize" by earthing it through the operation of the PTT which
connects the mic to the earth/shield.
I am probably expressing this badly but do I have it more or less right?
Will
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