In a message dated 15.11.99 11:54:42 Pacific Standard Time, K7GCO writes:
<< Dave
You are right. Open wire line with ice or snow on it against a blue sky is
absolutely beautiful.
The 4 to 1 balun at the end of the open wire line and then coax into the
shack seldom works well. Unless the Z is close to 200 ohms there and seldom
is, high SWR can result and is a bad design. The Z along a 450 ohm line can
vary from 50 to several thousands ohms and is not a good match to a 200 ohm
balun--as recommended by ARRL and others who never try it. RG 8 coax needs
about a 1/2" diameter hole to get into the house. Insulated open wire line
takes 2-1/4" holes. What's the difference and the easiest to repair and
conceal?
I adjust the tuner with a MFJ analyzer in the transceiver receive
circuit and a coax switch. This way I don't have to put a signal on the air
to check or tune the tuner. I record the tuner settings.
Long live Open Wire Line and Tuners.
k7gco >>
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