Help!! realistic Pro 2020
 

Don't know if this is the right group, but I'll give it a shot....

My mother-in-law was given a PRO 2020, and programmed the scanner, but can't
hear anything but static. She has asked me if I can repair it (since I'm a
former Navy RADAR tech). I think I'm on the right track here, but need some
tech support since I have been unsuccesful in locating a service manual. The
scanner does pick up the carrier and very faint audio/no static. I have
verified this by programming in the NOAA freq and turning the volume all the
way up. When I programmed in city police channel 1, all I get is static
until they key up, then it goes to the very faint audio/no static, until key
is released then static again. The squelch has no function at all. Also
doesn't scan, but this is most likely because of no squelch. I am leaning
toward the discriminator chip, has the functions of audio pre-amp, squelch,
and scan. Am I going in the right direction? Any techies out there?

Jim

Go here and you can get the Order Number
for the service manual: Call 1-800-THE-SHAC
http://support.radioshack.com/suppor...oc21/21316.htm

Most scanners pack the Disc/Squelch/Mute/Scan Control all
on the same chip. By looking at the parts list, it looks as if
our scanner uses a TD62501P for this, but without the service
manual, I cant tell. A google search for this part didn't find any
free datasheets. Good luck.

Tried that, even though it's listed in the parts list, RAD SHACK doesn't
show it in their system.


Jim

TD62501 is just a transistor array. Datasheet is at
http://doc.semicon.toshiba.co.jp/pdf...23/e005666.pdf

Another source I have shows the IF chip is MC3357.

"N3KCT" wrote in message
...
Go here and you can get the Order Number
for the service manual: Call 1-800-THE-SHAC
http://support.radioshack.com/suppor...oc21/21316.htm

Most scanners pack the Disc/Squelch/Mute/Scan Control all
on the same chip. By looking at the parts list, it looks as if
our scanner uses a TD62501P for this, but without the service
manual, I cant tell. A google search for this part didn't find any
free datasheets. Good luck.

Great! The Motorola MC33XX chips should be easy
to source. I was going by the parts list off of the 'Shack's
site that listed the TD62501 as:

IC103 10896413 TD62501P SQUELCH CIR MX4299

Found an mc3357 for around $4 I'll have to order it friday. Thanx for the
help.