MGL V6 Out of Band Rejection seems to be degrading
Posted: Tue Aug 27, 2024 5:04 pm
Hi,
I have an MGL V6 radio in my Zenith 750 STOL and I'm very happy with it. I've had the plane for about 3 years now and I've noticed that this year I'm getting significantly worse out of band rejection than I was in prior years.
The airport I'm out of has an FM radio tower near it on 107.7MHz at 30kW ERP and I've always had issues flying near it on my base to final turn. This year I've noticed that the interference from this tower is significantly worse than in previous years, sometimes extending miles from the airport.
I also have had noticeable interference from radio towers at other locations and frequencies when in previous years there was no interference. Just this last weekend I was flying near a tower (2-3 miles away) and I had solid static on the radio from about 5 miles out to 5 miles past the tower.
I've tried adjusting squelch and even at +15 I'm still getting interference.
I haven't been able to find a bandpass filter or something similar that would allow for transmit power to make it through unimpeded, so I'm at a bit of a loss as to what to do. I can't think of anything filter wise in the radio that could be degrading to cause this.
Do you publish specifications for out of band rejection for the V6? It could also be an IP3 issue with the front end being saturated, but I don't have a good way to tell. I don't think that's always the case because when I turn the squelch up high I can usually hear other aircraft on the radio, save for when I was flying close to the larger tower last weekend.
Does the V16 radio offer better rejection? I'm also in the process of building an RV6A and was considering the Vega and V16 radios. They're really capable units for their cost and the ability to dual monitor frequencies is a feature I'll never go without again, but I'm a bit at a loss on how to solve this particular issue.
Thanks,
Nick
I have an MGL V6 radio in my Zenith 750 STOL and I'm very happy with it. I've had the plane for about 3 years now and I've noticed that this year I'm getting significantly worse out of band rejection than I was in prior years.
The airport I'm out of has an FM radio tower near it on 107.7MHz at 30kW ERP and I've always had issues flying near it on my base to final turn. This year I've noticed that the interference from this tower is significantly worse than in previous years, sometimes extending miles from the airport.
I also have had noticeable interference from radio towers at other locations and frequencies when in previous years there was no interference. Just this last weekend I was flying near a tower (2-3 miles away) and I had solid static on the radio from about 5 miles out to 5 miles past the tower.
I've tried adjusting squelch and even at +15 I'm still getting interference.
I haven't been able to find a bandpass filter or something similar that would allow for transmit power to make it through unimpeded, so I'm at a bit of a loss as to what to do. I can't think of anything filter wise in the radio that could be degrading to cause this.
Do you publish specifications for out of band rejection for the V6? It could also be an IP3 issue with the front end being saturated, but I don't have a good way to tell. I don't think that's always the case because when I turn the squelch up high I can usually hear other aircraft on the radio, save for when I was flying close to the larger tower last weekend.
Does the V16 radio offer better rejection? I'm also in the process of building an RV6A and was considering the Vega and V16 radios. They're really capable units for their cost and the ability to dual monitor frequencies is a feature I'll never go without again, but I'm a bit at a loss on how to solve this particular issue.
Thanks,
Nick