US ELT Installation

T o d d P a t t i s t wrote:

"Wayne Paul" wrote:


Check CB radio shops or search Froogle for "SWR meter" for dozens
under $50.

The standard CB SWR meter's range is 2 to 30 MHz. For accurate measurements
you need one designed for VHF frequencies.


It's worthwhile comparing the measurements you get with the
two, which is what I did when I bought my CB-intended SWR
meter. (Used a Bird for the comparison) The numbers were
within 0.1 of each other over the entire aircraft band. Of
course, I bought my Radio Shack meter 10 years ago, so the
design may have changed. If anyone has a good VHF SWR meter
and wants to report a comparison with a current Radio Shack
(or other) model, it would be a valuable piece of
information.

I did the same comparison (also using a Bird instrument - shouldn't
every glider pilot have a Bird in his tool box?) with a 25 year old
Radio Shack model, and got the same results. Wayne and I discussed the
issue, and concluded that the CB units are probably just fine for SWR
measurements, so use it if you have one. The reason is SWR measurements
are ratio measurements, so frequency effects tend to cancel. Not so if
you want to do power measurements, for example.

Wayne suggested (and I agree) that if you are going to buy one, spend
the extra $10 and get one for our frequencies. Here are couple we think
would do the job, but we haven't actually used either of them:

http://www.thomas-distributing.com/meters-konnex1.htm

http://www.mfjenterprises.com/produc...rodid=MFJ-812B
(the $29 unit)


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA