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Old April 21st 06, 03:03 PM posted to rec.radio.shortwave
Dale Parfitt
 
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Default Coax Questions


"RHF" wrote in message
oups.com...
Robert 11,

Think about the Mechanics of it . . .

First you have an Antenna with a 50 Ohm Connector

Next you have a Coax Cable with a 50 Ohm Connector
on both ends.

Then you have a Radio/Receiver with a 50 Ohm Connector.

Note - 50 Ohm Connector = SO-239 Jack or PL-259 Plug.

Now when you go from the 50 Ohm Coax Cables (PL-259)
Plug to the 75 Ohm "T" Spliter {"F" Connector} ; you will
need an Adapter for SO-239 to "F".

Again when you go from the 75 Ohm Coax Cable's ("F")
Plug to the 50 Ohm (SO-239) Jack on the Radio ; you will
need an Adapter for "F" to SO-239.

That is a lot of Hardware Working and a lot of Electrical
Connections requiring a Solid Mechanical Connection.

Basic {Good} Antenna Building Practice :
Never introduce a Mechanical Connection into an
Antenna feed-in-line unless it is needed "By-Design".

Did I miss something in the post?
I see no reference to F connectors in the original post. or to a signal
splitter.
Also note ther is no such thing as a 50 Ohm or 75 Ohm UHF connector
(SO-239/PL-259) or a 75 Ohm F connector. Both of these connectors are
non-constant impedance connectors. Examples of constant impedance connectors
are N, BNC, TNC. SMA, SMB, SMC HN, etc.
If you use RG-59/U for your 75 Ohm section, no adapters are necessary. Just
use a UG-176 reducer in your PL-259's instead of the UG-175 reducer

Use your UHF tee Bob and put a vinyl cap over the male port. Losses at HF
are in the -0.01dB/connector region for properly installed junctions. Just
waterproof them.

Dale W4OP