Go to Radioshack.com.
Click the "Product Manuals" tab at the top.
Click "Communications."
Click "Scanners."
Click "20-148" or "20-148B."
Click "Detailed Parts List"
Look down the list of parts for the Service Manual
Take down the Cat# for it (10822963) and go to
the Shack and order it.

I see messages like this posted a lot here, I hope
this helps! Just pick the correct category and look
for your particular model.