Exploring FM simplex

  I haven't done much with amateur FM simplex on any band. It's something that has always seemed to be the domain of those with big antennae and powerful rigs, at least to me. It's certainly not an aspect of the hobby suited for HT operation. Still, the experiences that I have had on simplex have been very positive and interesting, and also completely counter to my pre-conceived notions. I've run into several new(er) hams on repeaters that also see FM simplex as something that's "not for them", so I thought I could share a few of my experiences and get a few people to experiment with FM simplex. 

  Long years on GMRS using a hand-made Yagi didn't really help to prepare me for amateur FM simplex. Once the big GMRS repeater in Golden Valley shut down, local operators were forced to switch to simplex, and the results were disastrous. UHF FM simplex is difficult without a directional antenna, and most of the operators didn't have one. I saw simplex as something that was useful for maybe five miles -- in other words, not that useful. 

  So, when I got my amateur licence, I was thrilled with the world of UHF repeaters that suddenly opened up. Of course, most of them were dead, but just the potential of reaching people outside of UHF simplex range was exciting to me. I think that most long-time hams have completely forgotten what that thrill is like, and they've become jaded by the ease with which their 75W rigs with rotating beams can communicate with people far away. Still, though I had access to repeaters, I did try UHF FM simplex several times. It was more out of a sense of exploration than any actual expectation of having a conversation. I found no one on the 446.000 frequency, and I had no way to determine how far I could reach. 

  It wasn't until I got in to 1.25M that I found out that I had any potential for FM simplex. KD0UDM (Neal) and I were in a QSO on a local 220 MHz repeater, when Neal suggested simplex. It was only about eight miles between us, and I had 25W running into a three-element Yagi, so it seemed possible. I didn't expect much more than a barely readable signal mixed in with the background noise, but it sounded like a fun experiment. To my complete surprise, we were full quieting and even clearer than we had been on the Arden Hills repeater. 

  That experience got me thinking. Though I didn't have a 2M beam, it might be possible that VHF FM simplex could be an option. At that point, I had an FT-897D and 50W, though my antenna was only a mobile whip. I threw out my sign several times on 146.520 without luck, and I began to think that 2M FM simplex wasn't a viable option for me. It wasn't until I ran into K0MPX (the weather station in Chanhassen) on 146.52 months later that I became convinced that VHF simplex was something that might actually work. 

  What I found over the next few months was that most of the activity didn't really take place on 146.520 -- which is the national calling frequency. I ran into N0KFB (Dan) on 146.580, and others on 146.500 (which isn't an allocated channel), and I got decent signal reports. And, a few weeks ago, I ran in to KC0WHJ (Dennis) and KC0FHA (Al) on 147.555. Dennis was only about 8 miles from me, but Al was about 30 miles away -- which was the furthest that I had ever reached. My success was mostly due to their superior rigs, but both of them were very encouraging about exploring VHF FM simplex further. Still, it's clear that you need to know where to look in order to make contacts. It's not the same as operating on repeaters in that regard. 

  UHF simplex still seemed out of reach, however. KA0KMJ (John) and I had successfully talked on 446.000 a few times, but he's only about five miles from me. KE0CRW (Greg) and I have also played with UHF simplex at QRP levels, but he's practically next door to me. Last weekend, though, KE0NA (Dave) and I tried a QSO on 446.000 -- a distance of nine miles. That seemed a bit far for simplex to work in an urban environment, and I was sceptical. Still, we both had 20W and beam antennae. It seemed like a possibility. What I found was something unexpected. 

  With only an S2 signal between us (at best), we were both completely readable. UHF doesn't have nearly the same level of noise as the lower frequencies, and the natural characteristics of FM worked in our favour. I don't think that doubling our power would have improved things much, and it seems as if we could have used less power and been successful. More than anything, UHF requires a clear, line-of-sight path. While there was only about 20 feet difference in our elevation, there were a lot of obstacles between Plymouth and NE Minneapolis over those nine miles. If both of us had 50- foot towers at our disposal, I'd have expected much better results in terms of signal strength. But, as it was, it worked remarkably well.

  What I took away from this is that UHF simplex is possible, and even enjoyable, in the right conditions. Even an HT, connected to a Yagi and given an unobstructed path (e.g. a hill overlooking your target location) could do pretty well on simplex. You might even run across someone that has 446.000 programmed in to their radio, and they might come across you while scanning. Realistically, though, I can't see amateur UHF FM simplex ever approaching the relative popularity of VHF FM simplex. If you had a good location or tower, you'd probably have better luck with GMRS in terms of finding someone to have a conversation with. 

  I've read on a British amateur blog about UHF SSB, with common ranges of 50 - 60 miles. That sounds intriguing, but it's another one of those things that nobody really does here, so you would have to set something up in advance. I've experimented with it before using vertical antennae (with AE0CX and N0YNT), but the results weren't very compelling. 

  I consider myself fortunate to have come across local operators that haven't lost their interest in experimenting nor their fascination with radio itself. When something becomes so easy, such as operating QRO with the best antennae, a lot of the excitement and mystery just gets drained out of the experience. FM simplex, to me, is interesting because it's a challenge. To others, it's just a way to isolate yourself from "the repeater crowd" and associate with a more 'refined' type of amateur. It's no more of a challenge than reaching a repeater for most of those on two-metre simplex. While I've no use for that kind of mentality, it's still something that remains interesting to explore, and I'd encourage new hams that haven't played with it to push at the boundaries and have some fun. That way, you won't get jaded and too 'experienced' to explore the various niches of the hobby.