The first thing is to check that you have the correct board. There are a coupe of version of the PL board in the Syntor. This describes the changes for the HLN4476 and how to change it from a fixed Codeplug version to a PROM version so you can have PL on each channel. This process will work with the other version of the PL board, but I think the part numbers and components are slightly different. Check the Motorola Syntor Manual for more information, the HLN4476 may only be in the manual revision pack, so get that if ordering from Motorola.
You will need the following tools to make it all happen, a small soldering iron, a solder sucker (spring loaded types work best) small snips, and needle nose pliers. Do not use the Solderwick type of solder remover, the will require much more heat and time then a suction device and will ruin the PCB. The solder suckers can be had for under 10 bucks.
Remove the PL board from the Syntor, and inspect and verify that you have the correct board, then remove the Codeplugs. Now it is time to do the dirty work, pretty much start anywhere and remove the solder from all open holes on the PCB. Use care not to damage the pads with too much heat. After all holes have been opened up you must remove the following components R23, R24, R25, R26, L4, Jumper JU14. The top and bottom of the boards have parts legends so locating parts should be easy. Clear the pad holes for L4 only as that part will be replaced, R105 is not used.
Start stuffing the parts from the attached parts list in the correct component locations. Parts should be labeled on the top and bottom so you can?t get confused. Note that R48 is labeled incorrectly (R84) on the top of the PCB, look on the bottom to be sure. Bend parts to fit either vertically (most resistors) just like existing parts. Solder and continue until all parts are filled. This includes sockets, and the Header for the new cable that will be attached later. Sockets should be used for the IC?s. Transistors should be inserted so the shape of the pattern on the PCB matches the actual part. Again, look at existing parts. Add a 8 pin header to the PCB at P3. Add in jumper JU8. This completes the transformation. Also check JU18, may need to be reconnected as well.
You must now make a cable that can reach from the bottom of the PL board, connector P3 which you added to reach near the PROM in the Syntor. You will need about 8 inches of 8 conductor cable and suitable connectors. Make sure the ends are labeled so that PIN 1 (GND) of the PL board (connector P3) matches with the connector on the Syntor motherboard. GND pins on the Syntor motherboard is at pin 8, and may be cut off on some models. This is normal, but just make sure that GND on the PL card (Pin 1) is GND on the Syntor (Pin 8).
he last step is to program the PL PROM, you can get several programs to generate the binary image and burn the PROM, so take your pick and go. Happy Syntor-ing. And here is the disclaimer, Do this at your own risk, if you smoke the radio or yourself tough luck, don?t blame me, do at your own risk?but have fun for sure!
Parts List for conversion of HLN4476 PL Board to PROM
Part numbers are as specified for the HLN4476 series board only. All resistor are ¼ watt. All caps 20v or better.
Part# Type
Q7 General Purpose PNP, MPSA56
Q15 General Purpose NPN, MPSA06
U5 Quad NOR Gate, CD4001
U6 Hex ?D? Flip-Flop, CD40174 (74C174)
U9 256x8 Bipolar PROM, 82S135
R27 4.7k
R36 5.6k
R37 5.6k
R40 6.8k
R46 5.6k
R47 5.6k
R48 5.6k
R49 5.6k
R50 5.6k
R51 5.6k
R52 82k
R53 220k
R54 82k
R55 10k
R56 10k
R57 10k
R58 10k
R59 10k
R60 15k
R92 2k Note Replaces L4
R101 10k
R102 47k
R103 47k
C26 0.01uf
C27 0.22uf
C65 220pf
C93 0.01uf
1 20 Pin IC Socket
1 16 Pin IC Socket
1 14 Pin IC Socket
8 Position Pin Header .1" spacing Single Row
2 Connectors 8 Pin Female Single Row
1 8" Approx. Ribbon Cable 8 conductor
JU8 Jumper wire
