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

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

what does it do to a set of phones or ext speaker?
my thought lie with a naff speaker.
even though the beep is ok.
have you a sig gen? or maybe stick a radio from the eaphone socket to two
bear wire and put them across the scanners speaker after disconnecting the
scanners own feed, does it work ok then?
you need to find out if it is the scanner at fault or the speaker as the
dirst step.
if an external audio source works, then time to scope the i/p & o/pof the
audio chip.
should be easy to do.

mike

"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

Thanks frank,

is this for the vol/squelch combi or can they be seperated?

regards,

Allen
"Frank346" wrote in message
...
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

"mikeFNB" wrote in message
...
what does it do to a set of phones or ext speaker?
my thought lie with a naff speaker.
even though the beep is ok.
have you a sig gen? or maybe stick a radio from the eaphone socket to two
bear wire and put them across the scanners speaker after disconnecting the
scanners own feed, does it work ok then?
you need to find out if it is the scanner at fault or the speaker as the
dirst step.
if an external audio source works, then time to scope the i/p & o/pof the
audio chip.
should be easy to do.

mike

Thanks Mike,


I tried an amplified source via the earphone. The
Amplifier was a Klipsch 2.1 (200 watts) the audio was barely intelligible.
the background hiss was overbearing
and a beep tone at the same amplified volume level was
well beyond tolerability. I will try your other suggestions
as I do have a tone generator that I could get out of mothballs.

regards,

Allen

Allen Crawford wrote:
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


Is the beep affected by the volume pot? I have the Pro-96 and the volume
control is awfully hair-trigger - goes from nothing to too damn loud in
the first few degrees of movement and then there's not much left for the
rest of the adjustment. It may be a 'design feature', though yours
suggests an actual fault of some sort. Can you get to the volume pot and
listen with an earpiece on the various pins to ground?

Cheers.

Ken

I believe it is for the combination. That might account for the high price.
The beep probably bypasses the volume control in the circuit. Since it is
loud and clear, the audio amp chip is ok and the speaker is too. Note that
the volume pot is 50K from one end terminal to the other. If you get a
higher reading than that from the center terminal to either end, that is a
clue that the pot is probably bad.

"Allen Crawford" wrote in message
...
Thanks frank,

is this for the vol/squelch combi or can they be seperated?

regards,

Allen
"Frank346" wrote in message
...
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

Component failure may have cause the IF freq. to shift off of the correct
freq.

HJ

"Ken Taylor" wrote in message
...
Allen Crawford wrote:
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


Is the beep affected by the volume pot? I have the Pro-96 and the volume
control is awfully hair-trigger - goes from nothing to too damn loud in
the first few degrees of movement and then there's not much left for the
rest of the adjustment. It may be a 'design feature', though yours
suggests an actual fault of some sort. Can you get to the volume pot and
listen with an earpiece on the various pins to ground?

Cheers.

Ken

Ken,

the "beeptone" is virtually unaffected by the volume
control and remains constant from the near off position to
max volume. I only wish I could get to the contacts
while the unit is powered up but it is sandwiched with
a lower speaker/display/keypad board and they will
not operate when separated. so all my experimentation must be done with the
component side only:-(\

regards,


Allen

"Frank346" wrote in message
...
I believe it is for the combination. That might account for the high
price.
The beep probably bypasses the volume control in the circuit. Since it is
loud and clear, the audio amp chip is ok and the speaker is too. Note that
the volume pot is 50K from one end terminal to the other. If you get a
higher reading than that from the center terminal to either end, that is a
clue that the pot is probably bad.

Frank,

I am inclined to go with that too. I am going to have to get the
spouse to help with the pot turning while I hold the fluke leads. I will
give back the readings with respect
to ground later and see what you think. there is a stack
of 3 soldered leads which leads me to believe that 3 are
on/off, 3 are volume, and 3 are squelch...darn squelch
definately wants to parallel the movement of the volume
too....damn poor design for such a nice spec'd receiver.

regards,

Allen