"N Cook" wrote in message
...
Model MDX C150 made for Japan use and FM band set to 76MHz to 90MHz, UK is
about 88 to 108 MHz

Monitoring the VT line to the tuner varies from 1.52V to 4.2V from end to
end of this band. 2 banks of 6 channels programmable in this 76 to 90 M
range plus 3 more that come up annunciated as 1ch with a VT of 5.66V, 2ch
of 6.83V and 3ch of 8.04 V which coincides with a local station on
107.8MHz,
B+(for FM ) on the tuner is 8.29V.

Other than shifting this VT voltage and a 'lying' LCD display anyone know
how to reprogram these extra 3 channels that don't respond to the Seek +
/ -
buttons or even better resetting the whole fm band.

Also what does BTM mean coming up on one button selection?

electronic hints and repair briefs
http://homepages.tcp.co.uk/~diverse




I changed the 7.2M crystal associated with the LC7216 PLL to a double PAL
frequency crystal of 8.867238M
and this brought the range up to almost ideal, a slightly lower frequency
would be better.
LCD reading of 80.0 gives a tuned in station on 96.1M and 89.5 on LCD gives
a station
at 107.8MHz.
7.2M is used on LC7218 FM circuits so probably fairly generally applicable.

Will eventually appear on repair file on
http://homepages.tcp.co.uk/~diverse
electronic hints and repair briefs , schematics/manuals list etc