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eHam Forums => Elmers => Topic started by: K2TGI on November 11, 2012, 03:28:41 PM



Title: radioshack pro-52
Post by: K2TGI on November 11, 2012, 03:28:41 PM

  Does anyone have a schematic for a radioshack pro-52 scanner,
  I was given one non-working and would like to repair it to monitor
  some local frequency's, I had no luck at all searching for it online . . . .
  I'm good on qrz.com for any emails . . . .
 
              thanks guys,  Hal K2TGI


Title: RE: radioshack pro-52
Post by: W5FYI on November 11, 2012, 11:57:53 PM
Email radioshack.com; they used to have all manuals online, but lately seem to have whittled it down to 194 or so. They still might have the scan, and could supply you with a copy.

Basic troubleshooting should get you in the ballpark. Does anything power up? If not, start at the battery terminals and trace voltage (or continuity) forward. Look for an open fuse (which sometimes doesn't even look like a fuse) or open PCB traces or broken wires through the on/off switch. If you can determine that the circuit is getting power, then trace backwards from the loudspeaker.

Maybe the loudspeaker doesn't work, but the earphone does--then it's a bad loudspeaker. You might want to check the electrolytics around the audio amplifier--they sometimes go bad and kill audio. If you have a signal injector, work backwards from the speaker until you pinpoint the problem. Most likely it will be a defunct capacitor or broken PCB trace.

If it's a bad IC, you might have to bite the bullet and give up. But, hopefully, it will be something simple like a fuse or open loudspeaker coil. Remember that about 75% of electronics problems are mechanical (e.g. broken wires, fuses, switches and contacts), so try to eliminate those first.


Title: RE: radioshack pro-52
Post by: K2TGI on November 12, 2012, 03:58:39 PM
  I tried radioshacks support website Claude, they have no copies of the manual or schematic in the archives,
  guess this ones going to the parts bin . . . .  


Title: RE: radioshack pro-52
Post by: K2DC on November 13, 2012, 06:39:35 AM
Many, if not most police and fire departments have switched to digital trunking systems for comms, making most older scanners completely useless unless you want to listen for businesses or the railroad or the like.  So even if you get it working, you may be all dressed up with nowhere to go.

73,

Don, K2DC