Switch Wiring Instuctions

EEPROM Pin Out Diagram: 

Referring to the graphic below, the "Asterisk" denotes pin-1 on all DIP (Dual Inline Package) styled chips. Some chips may have a "dimple" while others may only have the "U". The pin to the LEFT of the "U" IS pin-1, in case your EEPROM chip does not have the "dimple". 

The pin out on the EEPROM is as follows: 

1--|*-U-|--8 
2--|-----|--7 
3--|-----|--6 
4--|-----|--5 


Wiring Procedure: 

1. Drill a hole in the back of the IRD frame, and mount the SPDT switch so that the legs/pins on the switch are lining up in a vertical manner. 

2. Locate the serial EEPROM. This IC is an 8-pin chip usually surface mounted, and most are a Microchip 24LC16B. 

3. Lift pin-7. To do so heat the pad and use a dental pick tool to gently lift the pin from the copper land. 

4. Solder a wire from the lifted pin-7 on the IC to the center pin of a SPDT type switch. 

5. Solder a wire from pin-4 (Vss or Ground) to the bottom pole of the switch. 
(Do not use the pad from pin-7 since the space between the lifted pin-7 and the pad is so small, that doing so can cause short). 

6. Solder a 1K-Ohm ¼ Watt resistor to the remaining leg on the switch. 

7. Lastly solder a wire from pin-8 of the EEPROM to the free leg on the 1K Ohm 1/4 Watt resistor. 

With this modification controlling the EEPROM is now that much easier. 

Switch Settings: 

To UNLOCK the EEPROM, flip the switch lever so that it points UP. 

To LOCK the EEPROM flip the switch lever so that it points DOWN. 

  Eeprom Picture

  Wiring Instructions