As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DOESN'T REPLY. FOUND UNIT DOES NOT TRANSMIT OR RECEIVE. REPLACED OPEN RESISTOR R429 AND BAD DIODE CR404. REPAIRED RECEIVER PROBLEM. REPLACED CAVITY TUBE V101 DUE TO NO POWER OUT. REPAIRED. ALIGNED RECEIVER TO SPECS. REPLACED PHOTOCELL V301 DUE TO WEAK REPLYLIGHT. BENCH CHECK GOOD.