HOW TO INSTALL A MACHINE PIN SOCKET
REMOVING AN IC (TO INSTALL A SOCKET) IS USUALLY NOT A BIG DEAL. DOING THAT PROCEDURE ON A 30 YEAR OLD BALLY MPU IS A BIG DEAL. BALLY PRODUCED A PCB IN 1978 THAT WAS ABOUT THE MOST COST EFFECTIVE POSSIBLE. IT HAD COPPER PADS ON THE TOP LAYER AND COPPER PADS ON BOTTOM LAYER BUT NO CONNECTING “PLATE THRU” DESIGN. WHEN DE-SOLDERING A BALLY BOARD EXTREME CARE HAS TO BE USED TO PREVENT PADS FROM WORKING LOOSE. SOME PADS ARE CONNECTED TO TRACES WHICH PROVIDED SOME STABILITY, BUT MANY PADS ARE SIMPLY ADHERED TO THE SURFACE. THE BEST METHOD FOR REMOVAL HAS PROVEN TO BE THE SIMPLEST AND CHEAPEST.
WHEN THE BOARD BEING WORKED ON HAS THE TRADITIONAL ‘PLATE THRU’ DESIGN A HAKKO 808 IS RECOMMENDED.
HAKKO 808 COSTS FROM $150.00- $200.00 DEPENDING ON VENDOR. USE GOOGLE TO GET THE BEST PRICE.
THE HAKKO 808 IS A FINE TOOL BUT IT TENDS TO PULL UP PADS ON A 30 YEAR OLD BALLY MPU, ESPECIALLY IF THERE HAS BEEN ANY BEAD BLAST CLEANING OF ACID DAMAGE. ONLY SAFE METHOD IS SOLDER WICK REMOVAL. BELOW IS A TYPICAL IC 15 REMOVAL AND SOCKET INSTALLATION. SOLDER WAS REMOVED BY SEVERAL PASSES USING SOLDER WICK AND 60 WATT IRON. IF THE SOLDER DOESN’T WANT TO MOVE, PRIME THE AREA WITH SOME NEW SOLDER. THIS NEW MIX WILL HELP BREAK LOOSE THE OLD SOLDER.
SOLDER WAS REMOVED FROM ALL 14 PINS ON BOTH TOP AND BOTTOM OF BOARD. BENT PINS WERE LIFTED UP OFF SURFACE AND PLACED IN CENTER OF HOLE. IT MAY TAKE SEVERAL PASSES TO GET ALL THE PINS ‘FLOATING’ IN THE HOLES BUT IT DOESN’T TAKE MUCH RESIDUAL CONTACT FOR A PIN TO PULL A PAD UP WHEN CHIP IS PRIED OFF. AFTER BEING SURE THAT ALL SOLDER IS GONE, APPLY A LITTLE PRESSURE UNDER THE IC TO JUDGE AMOUNT OF TENSION LEFT BETWEEN IC AND PADS.
ANY STUCK PINS SHOULD BE SOLDER WICKED AGAIN BEFORE IC WILL ‘SNAP’ LOOSE.
SOLDERING IN A MACHINED PIN SOCKET IS DIFFERENT THAN WHEN USING THE ‘STANDARD’ TYPE OF SOCKET. IT IS NECESSARY TO PLACE THE SHOULDERS OF A MACHINED PIN SOCKET SLIGHTLY ABOVE THE TOP SURFACE OF THE BOARD. DO THIS BY TACKING 2 PINS ON OPPOSITE SIDES OF THE SOCKET TO OBTAIN A RAISED/ ALIGNED POSITION.
SURFACE IS SANDED TO PREPARE COPPER TO ACCEPT SOLDER
ONLY THE CENTER PINS ON BOTH RAILS ARE TACK SOLDERED AND SOCKET IS STRAIGHTENED. THE SPACE BETWEEN THE SHOLDERS AND THE PADS IS INCREASED ALLOWING FOR A WEDGE OF SOLDER FILLER. IF SOCKET WERE FLUSH TO SURFACE, THE SOLDER TIP IS UNABLE TO REACH UNDER THE SOCKET (IN TIGHT LOCATIONS) WITHOUT MELTING THE PLASTIC FRAME.
AFTER TACKING SOCKET INTO POSITION (ON TOP SURFACE), TURN BOARD OVER AND SOLDER ALL 14 PINS/ PADS.
NOW FINISH OF THE 14 PINS/ PADS ON TOP OF SOCKET. PLACE SOLDER TIP NEXT TO SHOULDER AND APPLY A SMALL BIT OF SOLDER. THE END RESULT WILL BE A PERFECT WEDGE OF SOLDER AND A TROUBLE FREE CONNECTION.
THE FINAL RESULTS SHOULD RESEMBLE THIS PHOTO. TOO MUCH SOLDER WILL TEND TO RUN OVER TO BARE TRACES.