engineerorange
Well Known Member
I have a SV-Comm, Dynon intercom and Delta Pop bent whip antenna on the belly.
In December when my plane first flew, radio transmissions were very broken on all frequencies. Parts of transmissions were fine, some words came through clear, some not at all, but the carrier was always present. Dynon said this is a known issue and had me clean the radio mounting points and add a ground wire from the case of the intercom to the case of the radio. This made zero difference. At that point, I suspected my antenna or installation so I hooked a handheld directly to the coax that I unplugged from the back of the radio and got 5x5 transmissions. I let Dynon know and they sent me a new radio. When the new radio arrived, I installed it and got carrier only, no sound at all. At that point, I suspected my antenna or installation again so I attached a mag mount antenna to the radio with a patch cable. I got good transmissions on the ground pointing me to my antenna or installation again. I made a new coax and temporarily installed it between the radio and antenna. I got good transmissions on the ground at that point, so I routed the coax permanently and tested again by talking to planes in the traffic pattern from the hangar. Problem solved I thought. A few days later it was time to go flying, and we again got very broken and weak transmissions on unicom(122.7). We tried a few different frequencies on the ground and found that we could communicate on some frequencies better than unicom and the test pilot took off for more testing. Once in the air he was able to talk to a control tower(128.15) about 12 miles away and they reported 5x5. He contacted ATC on 125.15 and they reported 4x5 with some background noise that made him sound like he was flying a helicopter. Air to ground on 123.45 was OK from some locations and not good from others. Back to unicom for landing and got carrier only.
At this point I got frustrated and decided it had to be the antenna, as that is the only thing that hadn't been replaced. So I called Don and he agreed to send me a new one, even though neither of us really thought it could be the issue since some frequencies worked fine. Today I installed the new antenna and guess what, same ****. So now the radio has been replaced, the antenna has been replaced and the coax has been replaced. Either I am capable of building an airplane including all the avionics wiring, engine building and air frame construction but can't install a radio, or I am the unluckiest person in the world and got 2 bad radios in a row.
Does anybody have any ideas or are these Dynon comms just junk? I have a Dynon handheld and it works great.
Thanks for any help,
engineerorange
In December when my plane first flew, radio transmissions were very broken on all frequencies. Parts of transmissions were fine, some words came through clear, some not at all, but the carrier was always present. Dynon said this is a known issue and had me clean the radio mounting points and add a ground wire from the case of the intercom to the case of the radio. This made zero difference. At that point, I suspected my antenna or installation so I hooked a handheld directly to the coax that I unplugged from the back of the radio and got 5x5 transmissions. I let Dynon know and they sent me a new radio. When the new radio arrived, I installed it and got carrier only, no sound at all. At that point, I suspected my antenna or installation again so I attached a mag mount antenna to the radio with a patch cable. I got good transmissions on the ground pointing me to my antenna or installation again. I made a new coax and temporarily installed it between the radio and antenna. I got good transmissions on the ground at that point, so I routed the coax permanently and tested again by talking to planes in the traffic pattern from the hangar. Problem solved I thought. A few days later it was time to go flying, and we again got very broken and weak transmissions on unicom(122.7). We tried a few different frequencies on the ground and found that we could communicate on some frequencies better than unicom and the test pilot took off for more testing. Once in the air he was able to talk to a control tower(128.15) about 12 miles away and they reported 5x5. He contacted ATC on 125.15 and they reported 4x5 with some background noise that made him sound like he was flying a helicopter. Air to ground on 123.45 was OK from some locations and not good from others. Back to unicom for landing and got carrier only.
At this point I got frustrated and decided it had to be the antenna, as that is the only thing that hadn't been replaced. So I called Don and he agreed to send me a new one, even though neither of us really thought it could be the issue since some frequencies worked fine. Today I installed the new antenna and guess what, same ****. So now the radio has been replaced, the antenna has been replaced and the coax has been replaced. Either I am capable of building an airplane including all the avionics wiring, engine building and air frame construction but can't install a radio, or I am the unluckiest person in the world and got 2 bad radios in a row.
Does anybody have any ideas or are these Dynon comms just junk? I have a Dynon handheld and it works great.
Thanks for any help,
engineerorange