There are two printed ciruit boards for the 77-285.
You must first determine which you have.
Circuit board "A" This board can be identified because D18 has been cut.
To restore full power simply resolder D18 or replace it.
Circuit board "B" On the "B" circuit board D18 is intact (has not been cut out).
To restore full power, locate D18 and trace the etch. Put a solder bridge between the open pads.
STEP 1. Take the bottom portion of the case off and unplug the speaker.
STEP 2. With the bottom of the case off, turn the radio over and in this position the Midland name should be upside down. Tilt the chassis forward toward the face plate. As you look at the inside panel the LC7232 IC chip should be readable and pointing toward you (upper right corner).You need to open solder bridges 5 and 6 from left of the chassis(bottom left).
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