How to convert a domestic analog FM radio to VHF ?
"Ridgh" wrote in
ups.com:
Hello,
I need to convert a domestic analog FM receiver to the 108-140 MHz
band.
I've bought a Sony ICF-S10MK2 receiver and found that the oscillator
tank has a 4 turns of 22 gauge. I've turned them apart, so the distance
between the turns will be a little greater than the factory adjusted
coil, and could receive up to about 115MHz, no more.
Is this the way to do it? Maybe to cut one turn will be better?
I'm not stucked to this receiver, I'd like to know if other cheap
receivers may be converted, and if this is the way, or if I have to
adjust anything else. I have all the gear needed, oscilloscopes,
counters etc. - but no much knowledge on this particular field.
I'll be very thankful for your help.
Ridgh
You might be able to get it higher with more inductor adjustments, I don't
know the circuit. Maybe have to add some capacitance to the tank.
Here's your real problem though. Broadcast FM is wideband. FM
communications 135-175 MHz are narrow band. That means more modifying is
needed to the receiver in order to hear the narrow band FM better.
It would be easier just to buy a cheap VHF receiver. Talk to the people
in rec.radio.shortwave for ideas on cheap plastic receivers. They're
experts.
SC
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