My last two flights my comm radio, Garmin Apollo SL40, started a “feedback” noise when transmitting or a sound like a double transmission. The tower couldn’t hear me well at all but enough to continue. I knew at the first of the year I was going to start annual inspection so I decided to start checking the connections to and from the radio.
Pulled it out of the tray, looked okay, disconnected the coax at the antenna and it looked okay. Didn’t remove the antenna but what I could see looked good.
Talked to support at Garmin and they talked about a SWR test with equipment connected between the coax and the antenna. This would determine it the coax and antenna are good.
I contacted an avionics shop at my home airport and left the radio with them for a bench check. This revealed an “over modulation” condition. The tech said it was putting out 30 watts when it should be only 10 maybe 16 watts. The radio needed to go back to Garmin for service and this will cost $875 and I believe when it is returned it will have a 6 month warranty.
The avionics shop still recommend the SWR check to be sure the antenna is okay as a bad antenna or coax could cause the damage creating the over modulation.
Has this malfunction happened to others?
Hoping this radio is worth fixing. 7 years and 490hrs of operation but a pretty pricey repair cost.
Is there another radio that would use the same tray? Basically a direct swap?
What comm radio option comes with the current RV12s?
Pulled it out of the tray, looked okay, disconnected the coax at the antenna and it looked okay. Didn’t remove the antenna but what I could see looked good.
Talked to support at Garmin and they talked about a SWR test with equipment connected between the coax and the antenna. This would determine it the coax and antenna are good.
I contacted an avionics shop at my home airport and left the radio with them for a bench check. This revealed an “over modulation” condition. The tech said it was putting out 30 watts when it should be only 10 maybe 16 watts. The radio needed to go back to Garmin for service and this will cost $875 and I believe when it is returned it will have a 6 month warranty.
The avionics shop still recommend the SWR check to be sure the antenna is okay as a bad antenna or coax could cause the damage creating the over modulation.
Has this malfunction happened to others?
Hoping this radio is worth fixing. 7 years and 490hrs of operation but a pretty pricey repair cost.
Is there another radio that would use the same tray? Basically a direct swap?
What comm radio option comes with the current RV12s?