Thanks to:      me (PoTom)
                        Virtual
                        TvMaN
                        AzRael
                        ][eBerg
                        [DoPeMaN]
                        BanpaiA team and everyone in #cellular

Requrements:    wire, soldering iron, screwdriver, pliers,
                        1/8" or 3/32" mono Audio jack,
                        20-30k ceramic Filter (SFG 455 B6 F; KBF-455R-20(30)A, etc)
                        0.1uF capacitor (not required).
 

1. Dissasemble scanner :
                        remove battery, antenna, knobs;
                        unscrew 4 screws on the bottom;
                        gently pry lower part of chassis;
                        unscrew 4 hex screws on top board;
                        unsolder 2 (volume and squelch) leads and 2 antenna leads;
                        disconnect 2 wires (squelch and volume) from sockets;
                         pull top board up.

2. Replace IF Filter to 20-30K one [#4],
       you may use Filter from Motorola Brick or Bag phone (ex: SFG 455 B6 F)
       or KBF-455R-20A (KBF-455R-30A) order from www.marshall.com.
        Find 3 filter solder leads [#7] on bottom side of the top board and carefully unsolder them
        pulling filter up, put new filter in that place and heat those 3 solder points pressing filter in.

3. Baseband audio(from discriminator) output.
        Find discriminator chip [#2] on top board;
        Solder one lead of  0.1uF capacitor [#3] to pin 9 [# 1] of discriminator chip [#2];
        Solder wire [#5] to second lead of capacitor [#3] .
        (you may   not install capacitor at all, everything will still work without it).

4. 800-900Mhz restoration .    (apllies to scanners produced before April 1994)
        If your scanner still has 800-900mhz zaps, to restore it go to lower board
        (unscrew 3 screws on middle board, disconnect power wire from lower board, pull board up),
        cut diode D-11 (Pro 34) or D-13 (Pro 37)   [#8].

5. Audio jack installation.
        Since I didnot find any good place for jack, I removed CHARGE jack [#9] from power board
        and installed audio one [#6]  in that place.
        Connection is simple , tip goes to wire [#5] , shield goes to GROUND (any place is good).
 
Assemble scanner and enjoy.
 
 

Top Board.

Bottom of Top Board.

Lower Board.

Part of Midlle Board (Power board).