I have recrystaled my older DEM (no-tune variety) 902/3 xvter so that 902 in
gives 144 out. This was mostly because there were more and more requests to
go to 902 instead of 903 where I had always been. I just tune 144 or 145
depending if I want 902 or 903.
Several people said that the noise from cell phone towers was lower at 902.
I do not find it so here however.(Ft Wayne IN, EN71LE)
I have greatly improved the noise situation by putting a three pole BPF in
front of the receiver. There is a small NF hit but not too bad. I have it
arranged with a transfer switch so can see the noise with and without the
BPF. Quite frequently the filter makes the band usable reducing a very high
noise level down to the occasional bleep or blop (new technical terms).
I built the filter from plans in the Ham UHF/VHF conference proceedings
literature which uses UT141 for the resonators. Can dig out the reference if
anyone wants.
Dan K9EA
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