hello reflectees !
The problem of protecting the rx front end while transmitting is a simple one.
Its very important NOT to use an extra RX jack (which most Radios have these
days)for beverage connection, You may create a loop on the backside of the
radio
as You have in this case two lines of considerable length attached to
it.Needles
to say that the RF potential will be different for both lines and compensating
currents flow thru the radio.And if switching this RX input fails for whatever
reason- the RX goes to smoke in a jiffy. Foolproof design is, to use only the
main TX/RX jack and to switch it via the PTT for the RX -mode into
filters/preamplifiers etc etc.If the switching in this design fails, You simply
replace the external preamp transistor and thats it. Mostly a "one Dollar
affair".
I built it this way and never had a failure in a many years.
73 de wolf -df2py-
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