[TowerTalk] 1/4 & 1/2 wl traps

[L. B. Cebik]

Apparently my last try did not get through.

Easy way to remember which trap does what with 1/4 wl:  the impedance at
the connection end is opposite the impedance at the far end.
Short = zero ohms, hence connection end = high Z--good for a series filter
connection for the frequency to be nulled.
Open = very high Z, hence, connection end = low Z--good for shunting
filter across the line to ground relative to nulling a signal.
These can in principle be used the other way around as band pass filters
rather than as band stop filters, but check effect on SWR for the range of
frequencies to be covered in operation.
Then:  1/4 wl short = 1/2 wl open and 1/4 wl open = 1/2 wl short.

Losses are low, but not zero, since the line has some loss, no matter how
short.

By now, this might be repetitive of other messages, but this will also
test if I am getting through with the revised UNIX system at this end.

-73-

LB, W4RNL

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