One of the repeaters I maintain has been working perfectly for almost a year since its last checkup. It is a 6m repeater that has a link to several other 6m repeaters, and is controlled by an ACC RC-96 controller. It is powered from a very large commercial UPS that ensures no-break power.
One evening, the controller went berserk, for no apparent reason. It started transmitting a string of Morse characters on both the primary and secondary ports: "dit dah dit ... dah dah dah dah dah dah dah dah dah dah ..." for about two minutes. It would then be quiet on both ports for about 30 seconds, and would then repeat. During the brief silent periods, the repeater would operate as a repeater, but the Morse string muted any other audio, once it began. The controller would not respond to my DTMF commands on either the primary or secondary ports. To make matters worse, the telephone line that gives me backup control to knock down the repeater was dead at the hilltop end! I had to make a hasty trip to the mountaintop site to take the beast off the air. As a result of this experience, I am adding a dedicated UHF control link to give me positive control of the repeater. Has anyone else had a similar problem with the RC-96 controller? Note that there is no lithium or similar memory battery inside the box that might go bad. Oddball malfunctions like this can add more gray hairs than I want! Any ideas, case histories, or suggestions will be appreciated. 73, Eric Lemmon WB6FLY
