C4FM?? HT 1/2 of summit conversation?

I am a new chaser. I learned about a S2S FM connection on the air near my home station. So I went to the frequency I was given and heard voices on the nearby summit. It was exciting.

And then I realized there was a problem. A friend of mine and I talked and he recognized the problem too. We only heard 1/2 of the conversation on our radios. I have a Yaesu FT-857D with a very good attic antenna. So what I heard came in clearly.

I wondered if he was using one of the Fusion HT’s which are a proprietary (no one else can use it on another radio) communication in their quest to dominate Ham Radio. Of course, as a world-wide business they would like to enfold Ham Radio into using their own system exclusively.

Was that really Fusion I heard (well I heard 1/2 of it). Is it common to use C4FM on Summits? If so, I will just have to stay away from people using FM on summits. I felt badly about that. If that is how it is, then that is what I will have to do.

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No. You heard part of the QSO simply due to the fact it was 2m FM and you were not ideally situated to hear all the other stations.


Thanks for your help. I guess I am used to hearing all sides of FM Conversations. Glad that you helped solve the problem.


Hi Peder,
I think the majority of FM QSOs you hear are probably over repeaters - the advantage with a repeater is that it sits on the top of a mountain or a high building or mast and can hear and relay signals in all directions. So you then hear both sides of the conversation, including stations on the other side of a hill which would normally block the signal from you.

Now consider putting an activator where that repeater is on the top of the hill and he can hear all the stations around him as there are no (or fewer) hills blocking the signals. In this situation, the station in one valley cannot hear the station in the other valley as the signal is not being relayed by the activator (and should not be).

It’s time you got together with your friend and head up to the top of a local summit (ideally a SOTA one but for this exercise, whatever you are comfortable with) put out a call (even with a simple HT rather than carrying the 857) on the FM calling frequency or a simplex channel and enjoy the advantage of height on VHF communications - I think you’ll be surprised and excited by how far you can get on VHF even just with a simple HT and its rubber duck antenna when you are in a good (high) location!

Above all - have fun
73 Ed DD5LP.