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Old September 6th 11, 05:58 AM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 1,169
Default MFJ-868 SWR/Wattmeter

Mike Coslo wrote in news:j43n06$ds52$1
@tr22n12.aset.psu.edu:

;... plus I keep it away from other people,
it's lasted FB.


That is probably key, don't trust other people... and be pretty wary of
one's self!

It is interesting you mention the Other Persons thing... I am in the
process of drafting a web article commenting on the advice that is so
common these days on online fora, "can you borrow an analyser?..."

This is almost always offered to some newbie who is having trouble
"tuning up his antenna".

Most don't understand complex numbers, impedance, transmission lines,
etc etc and someone tells them get an analyser and tune for resonance. I
can only guess that the advisers are equally lacking in knowledge and
experience, but I will concede that the analyser dumbed down to a VSWR
meter with self contained RF source than can be tuned outside band
limits, can be a pretty handy thing.

But despite the fact that adjusting many, if not most antennas for
minimum VSWR is the sensible objective, the resonance brigade chimes in
with make X zero looking into some arbitrary length of feed line, a
condition which isn't always associated with minimum VSWR and may
actually not be achievable. Some newbies have clipped their mobile whip
away to make that discovery, but perhaps without understanding that it
was a likely outcome from that strategy.

So Mike, it is likely that someone borowing an analyser to fix a problem
wont obtain real benefit, but may damage it in the process.

Owen