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Re: Re: Return loss bridge (2.4 gHz ) report



>From: "John / NS1Z" <ns1z@arrl.net>
>I had thought that would be a great kit BUT, for $150 one can buy a good
>(great?) commercial antenna with guaranteed results - no bridge required. I
>could see the benefit if I were to knock out antennas for the band of
>interest as a small business, but for a one off construction project... It
>just didn't fit in my $500 new "mode" budget.

Ah well, I can understand that {and respect why} you may not want to expend
the money, but I don't quite buy into your reasoning.

I have a Bird power meter with about dozen elements for frequencies from HF
to 1.8G and powers up to 2.5 kW.  If I were to buy it new that would amount
to something like $1,000.  I can buy several nice VHF antennas or a great
HF antenna for the money.  But that's not the only reason for having the
test equipment {having a good antenna}.

I intend to build up that 2.4G bridge, so I can determine not only my
antenna match but complete system performance.  With it I may be able to
monitor if something later goes bad.  I could make the same measurements
with my HP-432A and a directional coupler using low power [<10mw], but
would need to obtain a signal generator and coupler.  That might actually
make more sense, though cost me more dollars :-)

Many hams get by without test equipment, but others obtain at least some
basics for measuring voltage, current, resistance, power, swr, and
frequency.  I will grant you that measurements above 1 GHz require
different equipment than you mave have obtained already.  Eventually, you
will want something to tell you how your equipment is performing.  On the
microwave bands this is a little harder than say 2m where you can check
your unit out with a buddy on the local repeater, so having some test
equipment is helpful...when you decide you can afford it.

In the meantime you can observe the designs of others and copy them, and
use inexpensive methods such as peaking on sun noise, a signal source, or
off-air signals.

Ed

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