These boards are interchangeable with casework, keyboard, etc.; however, care must be taken to provide the customer with a unit that is compatible with their monitor and cable.

When component level repairs are necessary, be certain to acquire the appropriate part for the board you are repairing. Most modulators are different, as are many of the components.

* The 4th version of 64 board was recently developed and only a few may be in the field. It is termed the 64B-2. All circuits remain the same as the 64B (Schematic 251469) with a few component location changes:

1) Resistors 28, 29, 30, 36, 48 were reduced to Resistor Pack RP5.
2) Diodes CR100-105 are no longer piggybacked. Their new locations are CR9, 12-16.