The Intek 520 Plus CB will also tune the 10 meters amateur band in AM and FM with a couple of small mods. Step one is to remove the batteries and find a small
link (loop of wire). Cut the loop and separate the two sides, this tells the radio that its being sold outside europe. Step two is to select the correct
country. Code Po (Poland) will tune entire range of the radio in 10Khz steps - correctly aligned for the FM part of the 10 Meter bandplan, Keep pushing buttons
until you find the block of 40 channels ending in "I"
Channel 34I = 29.600 Mhz, 35I = 29.610 etc etc
As the VCO is running towards the band edge the FM modulation is a little bit low. The second mod requires opening the unit, remove the screws top and bottom,
this radio is pretty easy to get into, a few plastic clips around the side.
Locate variable resistor RV701 - towards the bottom of the PCB, this is the deviation POT. With the batteries fitted you can transmit with the radio in two bits, if you
have a deviation meter then knock yourself out - everyone else its easy - wind it to max ! ..... I know it sounds a nasty thing to do, but the deviation is pretty low
on the ones i've tried, its also limited so winding it up all the way will not distort the audio and will give enough deviation to sound pleasent on most 10m radios.
The radio comes with a complete circuit diagram and a useful block diagram. If your technical and can be bothered it may be possible to get more audio by changing
the resistor on the condenser microphone, find R743 22k and replace it with say 10k, the risk would be that in AM mode it may start to clip. I found adjusting the deviation pot
gives enough audio.
The radio is pictured here tuned to my 10 meter gateway on 29.630 Mhz, the gateway is only a few meters from the radio so im using the lowest possible power
setting (100mw). If your looking for a 10 meter FM handheld radio then this is pretty good, the price is a little bit steep - I got mine second user on ebay for around 75 quid, expect
to pay 100ish for a new one.
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