Extending Icom AH-4 tuner control cable
I need to extend the control cable for my AH-4 tuner. I have lots of Cat 5
Ethernet cable. The four leads to the tuner are Key, Start, +13.8Vdc, and
Ground. I initially hooked up each to each of the four pairs in the Ethernet
cable (i.e., Key to Blue/Blue-White). My thinking was parallel each pair so
I have less current loss, but I think I blew the capacitance out of the
water and the Key/Start pulses are getting smeared along the 100+ foot run.
What's the best way to wire things up so to the twisted pairs so any RFI
gets nulled out? Ground to each of the 4 White leads, and Key to say Blue,
Start to Green, and +13.8V to Orange? That way each twisted pair would have
a "signal" and ground. Or I could use the Brown for Ground, and connect the
AH-4 factory cable's shield to the four white leads. Which is the preferred
route for minimizing RFI or cable capacitance affecting the Start/Key pulse
signals?
Jon - KB1HTW
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