cgmg
Senior Member
- Joined
- Oct 30, 2003
- Messages
- 1,149
- Location
- El Paso, IL.
- Aircraft
- Empty hangar right now, have owned and flown Air Command & RAF
- Total Flight Time
- 375
I have an Icom A4 handheld I'm using with my Sigtronics intercom. I'm using battery power, not engine power.
The rubber whip antenna is mounted on the nose of the cabin with a right angle adapter at the cabin wall. The extension cable is 3' long, and both ends have a plastic cover on them.
Sitting on the ground, nothing running, I can hear Chicago ATC, and the pilots talking to them, over 100 miles away. Loud and clear, no static.
Engine running, I can barely tell what they're saying, due to the static. The volume level also has dropped by about 80%. Adjusting the intercom volume or the headset volume does nothing to increase the sound level.
The static only appears while there are transmissions. I have isolated the static cause to the fuel pumps. For some reason, the aux fuel pump creates more static than the main pump.
If I shut off the pumps, the engine will run about another five seconds. I did so during a couple of transmissions, and while the engine is still running, but the pump is off, the voice clarity returns.
One thing I forgot to do this morning while troubleshooting was put the whip antenna directly on the radio, bypassing the extension setup. Will do that tomorrow.
One thing I have sourced is an RG400 cable, if the popular response favors that. Don't remember where I bought my current radio cable, but since both ends are covered, I'm assuming(and you know what that means) it's not a cheap cable.
I'm not concerned about long range transmitting. I know that this radio was transmitting about 5 miles out when I used it on my AC, which is more than adequate for where I fly.
OK, all you radio technophobes, what's my problem?
The rubber whip antenna is mounted on the nose of the cabin with a right angle adapter at the cabin wall. The extension cable is 3' long, and both ends have a plastic cover on them.
Sitting on the ground, nothing running, I can hear Chicago ATC, and the pilots talking to them, over 100 miles away. Loud and clear, no static.
Engine running, I can barely tell what they're saying, due to the static. The volume level also has dropped by about 80%. Adjusting the intercom volume or the headset volume does nothing to increase the sound level.
The static only appears while there are transmissions. I have isolated the static cause to the fuel pumps. For some reason, the aux fuel pump creates more static than the main pump.
If I shut off the pumps, the engine will run about another five seconds. I did so during a couple of transmissions, and while the engine is still running, but the pump is off, the voice clarity returns.
One thing I forgot to do this morning while troubleshooting was put the whip antenna directly on the radio, bypassing the extension setup. Will do that tomorrow.
One thing I have sourced is an RG400 cable, if the popular response favors that. Don't remember where I bought my current radio cable, but since both ends are covered, I'm assuming(and you know what that means) it's not a cheap cable.
I'm not concerned about long range transmitting. I know that this radio was transmitting about 5 miles out when I used it on my AC, which is more than adequate for where I fly.
OK, all you radio technophobes, what's my problem?