In a message dated 97-10-31 06:14:04 EST, n4zr@contesting.com writes:
<< >
> 73, Pete Smith N4ZR
> n4zr@contesting.com
> >>
>How much of the loss can be attributed to the connectors?
>
>Tom, K5RC/7
Good question, Tom -- I recall a discussion here where it was argued pretty
persuasively that UHFs have virtually unmeasurable loss at HF - but my
feeder has 1 UHF at the Amp, another at the bulkhead, a third at the
outside of the bulkhead, another at the start of the hardline, another at
the end of the hardline, one at the antenna switch, another out of the
antenna switch, and finally another at the balun. Let's see .... that's 8!
Now, my measurement involved only 2 of those, but the total certainly
bears thinking about.
73, Pete Smith N4ZR
n4zr@contesting.com >>
The reason for asking is that many who use CATV hardline do not go to the
trouble (and it is a pain) to secure the appropriate aluminum connectors. In
years past, I have spliced RG213 to a piece of hardline, did a respectable
weatherproofing job and thought I had it wired. Six months later, the splice
looked like an experiment in cathodic chemistry. Since then, I use the
connectors and coring tool from the manufacturer and find the entire system to
be extremely low loss and reliable.
For those who are using CATV hardline for a single band, series section
transformers work extremely well for impedance transformation. They are
discussed in the ARRL Antenna handbook and practical dimensions have been
published several times in the NCJ.
73 and DX,
Tom, K5RC/7
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