When you use the receive line in the IC765/IC781 (by
removing the jumper on the back of the radio)for an receive
only antenna, be careful to make certain that the receive antenna
does not have so much transmitted RF on it that it causes
front end problems for the Icom radio. Front end damage can occur
and it also it appears to disturb the power supply causing the
radio to shut down.
I use an external relay that disconnects the RX ant from the radio
during transmission and also connects the RX antenna to ground.
Never use a diode across the RX antenna to limit
potential damage as it may cause RFI.
A nice article was written by KD9SV in a recent (Feb or March)
issue of CQ which described a good method for protecting
front ends.
73!
Tim
K3LR
K3LR@contesting.com
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