Hi Guys,
When 8.33 Khz spacing became mandatory in Europe, I purchased a Garmin GNC255A VHF radio. Also bought a GMA240 audiopanel and kept the SL30 as a second radio.
When using the GNC255A I get a terrible whistle when pushing the PTT button. When I start to talk the whistle reduces but does not go away completely.
I tried every combination on the audio panel but that does not help.
Selecting COM2 (SL30) gives a crisp and clear sound without any whistle.
With the experiment, I think I isolated the problem to the GNC255A but I am no avionics expert. Thought I would give this forum a try for advice.
It sounds as if there is some sort of open loop whereby I re-transmit my own transmission. I pulled out the co-pilots headset too without success.
Is there some sort of internal setting I can tweek to make the whistle go away ?
Thanks in advance !
When 8.33 Khz spacing became mandatory in Europe, I purchased a Garmin GNC255A VHF radio. Also bought a GMA240 audiopanel and kept the SL30 as a second radio.
When using the GNC255A I get a terrible whistle when pushing the PTT button. When I start to talk the whistle reduces but does not go away completely.
I tried every combination on the audio panel but that does not help.
Selecting COM2 (SL30) gives a crisp and clear sound without any whistle.
With the experiment, I think I isolated the problem to the GNC255A but I am no avionics expert. Thought I would give this forum a try for advice.
It sounds as if there is some sort of open loop whereby I re-transmit my own transmission. I pulled out the co-pilots headset too without success.
Is there some sort of internal setting I can tweek to make the whistle go away ?
Thanks in advance !