To retain memory in the RM-76, an optional DC Cable and usersupplied battery may be used. This would be useful where transferring the unit Base to Mobile, or when operating on an AC supply which cannot be run continuously.

Connect a DC Cable assembly, E30-0220-05, as illustrated. This will connect at the RM-76 rear panel.

Battery recommendation is 7.5V DC.

Current drain is less then 50mA at memory on.

When servicing an RM-76 for IC5 failure, also check pin 39 vdd voltage which should be approximately 6 V DC. Higher voltage will lead to premature second failure. An incidental symptom for this problem would be such reports as all "8's" before total failure.

Replace IC5 and IC2, NJM78L06A, the 6V regulator for the Microprocessor. Also check IC1 FS7806M, which supplies regulated 6V for all other sections. Failure of this regulator (at about 10V DC) will give all logic hi's.