PRO2026.1

    Hello from WD8RNG, Tim in Mentor,Ohio.
The following information is what I have obtained from the service manual
for the Radio-Shack Pro-2026 mobile scanner.The service manual is availible
at Radio-Shack for oprox. $6.00. To restore the missing segments of the
800 mhz band, remove the speaker side cover of the scanner.There is a small
connector mounted on the main circuitboard that connects the speaker,this can  
be unpluged for better access to the pcb. Near the front of the scanner on the
inside there is a smaller circuitboard mounted at a slight angle. On it there
are two ribbon connectors to the rear of this pcb. Also there is a so called
inductor labeled "L201" that is really a jumper that deletes the cellular
portion of the 800 mhz band. Just snip it open and spread it slightly so that
the ends do not touch each other. I also added a 9 volt battery to extend the
memory that is normally only good for about 30-45 minutes when power is removed. 

   The orange wire on the power cable is used for memory back-up. I sniped it

off on the inside of the scanner about 1/8 inch from the pcb,twisted it and

pulled of the insulation and tinned it for use as a terminal post for the 

positive side of the 9 volt battery. I mounted the battery behind the keypad 

on the inside of the scanner.

I added some cardboard around the area where I was going to put the battery so

it would not short to any components or pcb. I used some fiberglass tape to

hold the cardboard in place. The battery should be connected between the 

circuitboard common or ground and the tinned end where the orange wire was

connected. The remainning orange wire can be taped at the end and not used.

  I checked the current that the 9 volt battery drew when the scanner was not

connected to a 12 volt source, it measured about 2 microamps, which should

last almost the shelf life of the battery. I used a "Duracell" and the memory

has held up for months. I also did not like the beep every time I pushed a 

button on the scanner especially when head-phones were used. To get rid of 

this I removed the ribbon from the connector directly behind the back-light 

lamp for the display. To remove the ribbon push down on the white base and

carefully pull the ribbon out. The connector is spring-loaded. I bent back

the fith wire on the cable and reinserted the ribbon into the connector.

When you count the fith wire over, the scanner is laying upside down and the

front facing you. There are some more mods I am planning on doing like built-

in "PL" and "DPL" decoders, or a lowpass filter built in and brought out

to a jack at the rear pannel where external decoding devices can be connected.

   Well thats about all I have for now.....73 from WD8RNG