2m Bandpass Filter
On Feb 19, 4:38*am, wrote:
I recently acquired one of these cheap 2m handhelds from China, an
FDC-150 I think. It's great for the price (£30) apart from a problem
with QRM.
I use the radio with a 3 element beam from SOTA activations from hill
tops. It varies from location to location, but I often get strong
intermodulation effects (caused by pagers I think). I suspect the
radio, being wide band 136-174MHz, has insufficient filtering to
reject these strong signals.
The intermod is a real problem, as I am often unable to hear stations,
or only get half of what they are saying before they are wiped out. I
was wondering about building a 2m bandpass filter like the one athttp://www.arrl.org/tis/info/pdf/0005054.pdf
Does this look like a good bet?
Also any ideas where I can get the semi-rigid coax (UT-141 or RG-402)
in the UK?
If you are right about it being from a paging system the problem may
have nothing to do with the quality of radio you have. I have
experienced the same thing with a cavity filter on the front end of a
rx. Often the problem is with the pager transmiter. In that case no
amount of filtering will help.
Jimmie
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