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Old March 1st 06, 12:30 AM posted to rec.radio.scanner
Frank346
 
Posts: n/a
Default Pro 97 volume problems

Might be a bad pot. If you have a meter, with power off measure resistance
from center terminal of the pot to ground. Turn the volume knob through its
range. If there is no resistance change, order a new pot. This is what I
have for ordering the volume pot: 12429163 POT VOLUME 50K OHM $15.89. Be
sure to verify the correct part number if you do order one so you don't get
the wrong part.

"Allen Crawford" wrote in message
...
I recently purchased a pro97 scanner in near new condition over the

internet
through ebay. The item was
listed as having very low audio such as one has to place the speaker next

to
his ear to hear the broadcast so I took a chance and bought it for 45
dollars. I got it in yesterday and it is totally new! packaging, all
accessories, books and not a scratch on it. Well. I unpack it and install
freshly charged (new) batteries and
I go to playing with it..first..a weather channel..sure enough, very low
volume even when cranked to the fullest
it is still at the same volume level. I went ahead and took out the four
back cover screws and examined the area
where the volume pot is soldered and took some readings. center tap is
about 2.1kohm and 200 k ohm on the non grounded side. (this is without

power
applied)
in the area of the volume/squelch pot, are 3 tiny pots
and 3 test points...(this is all from memory as the scanner
is closed up now). I was hoping for a misplaced speaker magnet or

something
simpler and the circuits are ungodly
miniature and even the audio amp chip is about the size of an op amp on

most
regular size circuits. The doggone thing is so new looking, that it may

be
swapped with a
newer one from radio shack (by swapping backplates) but I don't dare

attempt
the dishonest. Anyway, any suggestions to resolve my dillemma...could it

be
possible that I have a defective volume pot? No amount of regulation seems
to affect the audio at all. The channel
beep come through loud and clear but it seems that either
the preamp from the radio is set too low or the pot is defective/soldered
wrong. Of course, the possibility of
a bad IC has crossed my mind as well. Any suggestions?
No warranty so all I have is either a repairman or my good wits and some
knowledge to help correct the problem. Btw, the sqelch seems to work OK.

Your input would be greally appreciated,

Allen