Re: W9RM January VHF
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Keith Morehouse
A few other things, just among us local boys and girls... I have found using a full-band spectrum display a MUST in this period of the rise of the machines. When the only signals on the band are currently on 50.313, and you are concentrating on trying to work someone there, you need to be able to see what's going on 'down the band'. On 6M, I use a external SDR, matched in sensitivity to the best of my ability with the main receiver, driving one of various software packages (HD-SDR, ect). A quick mouse click in HD-SDR commands the main receiver to that same frequency and you can hear what's going on. One can also see meteor bursts lighting up the MSK144 frequency or any other signal that might warrant your attention. It's sort of like having a master and slave station on a single HF band like we used to do back in Multi-Multi contest station days. With many modern radio with built-in waterfall displays, this capability can be routed out to a monitor for easy viewing and no other equipment is needed. I cobbled one up on 2M the morning of the contest but soon found it was deaf and needed a pre-amp. Even with the deaf SDR, during times I didn't have 2M in one ear, it clued me to someone on 144.200 and allowed me to quickly change main focus to 2M - I run full SO2R in VHF contests, with 6M as one radio and everything else as the other radio. Seeing that I'm in DM58 and not FN41, the right-hand (non-6M) radio lives on 144.200 almost exclusively. When I had other bands in the air, they were all switchable through this 'right-hand' radio via a switch matrix, where any band was available with the push of a button. In DM58, the only band changes were to follow a station worked on 6 or 2 up the bands if he had more then the bottom two (hardly anybody). Back in EN52, I had 2, 222, 432 and either 900 or 1296 on the matrix and a loud station with an experienced op could be worked on 5-6 bands within 90 seconds - even Rovers. I briefly touched on 2M FT8, let me amplify. Before the contest, I didn't think about FT8 on any band besides 6M, even though I know guys back east and in the PNW have been experimenting with it for a year or two. I didn't even know that a 'standard' frequency had been 'allocated' (meaning thrown out there for better or worse) by the WSJT-X package - 144.174 So, during the contest, on PingJockey, when asking a station west of Salt Lake City for a 2M run, which we would normally tough out on MSK144 (way too close for effective meteor scatter), it was suggested we try FT8. Well, we immediately made the QSO, in less then a minute, with easily 20+ "funny little numbers" margin (inside joke - FT8 generates a "signal strength" number automatically. FT8 will decode down to about -24. The SLC station was +5, which in the non-machine world would be easy CW copy in SSB bandwidth or Q5, but weak, copy in SSB on a quite band. So, +5 is a huge margin as far as FT8 is concerned). Yes, MANY of these FT8 QSO's can easily be done on CW - but, it's CW.......those with experience on VHF bands and can actually copy CW can identify the problem with that right away - sigh, After that, I went on to work a couple other 7's in that same area using FT8. All these guys would normally be worked quickly on CW or on brute force MSK144, which takes a while. All these FT8 Q's took less then a minute and all had ample margin. I then was asked to run by W7OUU in DN22. We pretty much work every contest on 2M using MSK144 meteor scatter, but again he's "only" 435 miles away, which is a bit close. He also runs a KW and stacked beams and I've worked him on terrestrial before, using, I think, JT65 - which takes forever plus 1 day. I suggested using FT8 instead and we worked easily with maybe -17 to -15 strength. This suggests we still had 6-10 'funny numbers' margin. Think about that - 435 miles, in the winter, over difficult terrain on 2M - with margin ! Sure, I have a good shot in that direction - I can see the mountains north of Grand Junction, almost 80 miles away, by eye, from the ground - but still. Later, I went on and worked N7EME near PHX using FT8. This was a bit harder as the mountain cyclical fade was bad, but we still accomplished it in well under 6 minutes. As a rule, I can't work into PHX on 2M terrestrial - I must use meteors. I'm 100 miles closer then the W5UHF station, but my path is awful. To further show the potential AND potential DOWNSIDE of 2M FT8, I'll finish with this - toward the end of the contest, K5LA from El Paso came up on PingJockey and I convinced him to give me a call on 2M FT8. He is a big station, but almost 500 miles away, across closer in rough terrain (the San Juan range at 14,000, 40 miles south of my 5800' QTH). I actually copied three STRONG traces of FT8 immediately and verified it was him by the offset. I would estimate these traces were in the +5 to +10 FT8 signal strength range (this is SSB copy). No decodes were to be had because of a combination of severe multi-path and meteor pings and we eventually needed to go to MSK144 to finish the Q. Yeah - we might have worked on SSB right away - no telling. But the point I want to leave you with is we had 20 'funny numbers' of margin if there hadn't been other propagation issues. I have worked him before on CW, but I recall it was very difficult. Take away the meteor pings and maybe it's not difficult. . . or maybe it is. Fun stuff - the kind of stuff that might keep you interested or might prompt you to improve your station. -W9RM Keith J Morehouse Managing Partner Calmesa Partners G.P. Olathe, CO
On Mon, Jan 21, 2019 at 12:44 PM Mike WB2FKO <mph@...> wrote:
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