Loose Notes 10/11/15

  Not a heck of a lot has happened in my radio world this week, but I'll try to put something together. 

• On Wednesday (10/7), the RF link between the 1.25M 223.940- repeater in Arden Hills and the HandiHam network was restored by KG0BP (Chris) after being down for nearly two years. Chris received substantial help from N0BVE (Don), who provided a tower. The signal from the 223.940 is received in Richfield and sent to the network via EchoLink, and any traffic on the network is transmitted to the 223.940 repeater with an Alinco mobile. I had a chance to test it out yesterday (10/10) with KA0PQW (Matt) and Don, getting in easily with 10W into a mag-mount tri-band whip from the opposite side of the metro. Don was also on 1.25M, so I had a chance to hear the audio directly and it's pretty good. The .940 will get a work-out with all of the traffic on the network. Thanks to everyone involved in this useful project. 

• As part of this upgrade by KG0BP, the 444.850+ (114.8 PL) HandiHam repeater is back on the air. In contrast to my discussions with Chris last November, he decided to use the old antenna that the .850 used before, rather than a north-facing beam. At only 13 miles distance, I'm unable to "ker-chunk" the .850 nor even hear any of the network traffic carried on it. Don has worked it from about seven miles at the University, and Chris' wife has worked it from about five miles distance. Undoubtedly, topography is the major limitation here. In its previous incarnation, the 444.850 had quite decent coverage to the south, and it's likely that it still does. Try it out and put your signal reports on RepeaterBook. Some operators in the inner southern suburbs might find the .850 a welcome alternative to the .650, as it's not plagued by a short time-out. The 444.850 is a fully-functional linked network repeater, so reaching it re-transmits your signal on every other HandiHam repeater over three bands.

• In an on-air chat with N0YNT (Matt) over DMR (N. America TG), I learned that he will moving back to St. Paul (from San Francisco) in 3 or 4 weeks. We discussed moving the 223.900- repeater to the St. Paul campus (definite maybe), and the 224.940- machine to K9EQ's (Chris) site (unlikely). Matt also has some hazy plans for the 443.425+ and 147.150+ repeaters that have more or less languished for years. Before his move to the West Coast, Matt expressed a vision for an ambitious metro-wide, linked, cross-band network. The pieces are finally coming together, with various people contributing their unique talents and thinking outside the conventional box. 

•  A chat with N0GOI (Terry) revealed that his six-metre FM repeater project (53.470-) is "not that far off". Two years ago, the TCRC's 53.370- machine died a whimpering death and left the metro without 6M FM coverage. Last year, W0CE (Charlie) informed me that his 6M repeater in Ramsey was, indeed, off-air, and would not be restored. N0BVE (Don) has been looking for a site for his 6M repeater for years now. I'm unsure how much interest there is in the metro for the six-metre band, at least as far as FM goes. With three bands already, and activity declining, it might be a "tough sell". In theory, the lower frequency should provide somewhat better "over-the-horizon" coverage (all other propagation anomalies aside). I could see more value with six-metre FM as part of cross-band linked system than as a stand-alone option. 

• In a QSO with K0ZZK (Tom) on the 444.475+ (118.8 PL) repeater yesterday (10/10), I learned that the antenna for the Richfield (RARC) machine has been upgraded. I was fairly surprised to reach it so well with an indoor antenna 13 miles away, especially considering my complete failure to reach the 444.850 (in the same city) with an outdoor antenna. Tom gave me a good signal report, however, and the .475 came back to me with an S6 signal here in Plymouth. Per Tom, the cross-band link to the RARC's 145.390- (103.5 PL) is no longer working and the idea has been abandoned. Still, the UHF .475 is a System Fusion machine, which offers potential for WIRES-X linking if the RARC ever wanted to do something creative with their coverage. For example, a WIRES-X link to the 442.075+ C4FM machine in Prior Lake (18 miles away) would be mutually beneficial. It would open up more of 169 and 35W to the metro and boost the fringes of the 444.475's coverage. As it stands now, though, the upgraded .475 has excellent coverage. I just need to find out how well I can reach it with 10W in my car this far away. 

• Not satisfied with being a major metro APRS gateway, N0AGI (Nagi) has teamed up with N0BVE (Don) to put N0AGI-5 on the Chaska water tower. This moves the I-Gate about a dozen miles north, and much higher. The results are very impressive. The map of stations directly heard shows that coverage for the west metro (which has always lagged) and the north-west metro (always spotty) has now dramatically improved. Keep in mind when looking at that map, that this is showing the results from less than a week at the new site. There still might be a gap between N0AGI-5 and the Litchfield KD0JOU-2, but the odds of getting your packets gated in the west metro are now pretty good. The map doesn't show coverage from digipeated stations, so this is a worst-case scenario...and it's very good. More information on the new gateway can be found at Nagi's blog.

• Nagi is also involved in another project: a WinLink gateway and packet node on 145.670. Per Nagi, this is actually three different projects. N0AGI-10 is a WinLink gateway that allows access to mail over RF. N0AGI-15 is a KA-node for packet allowing you to link to other packet nodes. And N0AGI-5 is a BBS (bulletin board) for posting messages, accessible over RF. Nagi is very keen to have others test this out and make use of it. Remember, packet works over FM. Your standard FM mobile, connected to a TNC and your computer, will allow you to do access these nodes (and other nodes on 145.110). While I'm just getting in to packet through APRS, I'm not familiar with anything outside of that. Nagi has generously agreed to advise me on how to set up a working packet station, and I hope to share that information here on the blog in the future.

• After being unable to reach N0YNT's (Matt) UHF SNP repeater on 443.000+ (118.8 PL) for a couple of weeks, I was surprised to find it working this week. Located in St. Paul, it's been around for years. Hopefully Matt can find time to look at it when he returns to Minnesota in a month or so. 

• On the other hand, I'm finding it increasingly difficult to get in to the 444.950+ (114.8 PL) repeater in White Bear Lake. I haven't been able to raise it in my car for over a month, nor with an indoor whip. I takes an outdoor antenna and at least 10W to open it up. A few months ago, I was able to work it with an HT/duck indoors. 

• The MARA 444.800+ (114.8 PL) continues to struggle. If you use this machine regularly, you are probably aware of it's annoying tendency to shut down completely for ten minutes or more if a QSO goes beyond six or seven minutes. In a QSO with KG0BP this week, it went dead just as we were discussing the effort to restore his UHF .850 repeater. It's smart to agree to a backup QSY when using the .800 repeater.

APRS without a ham licence?

 While this isn't directly related to amateur radio, I came across this post on another ham radio blog. It refers to a new device called the "goTenna" that pairs with a smartphone for data coverage on "the ultra-low-band frequencies 151-154 MHz". If that's ultra-low band, then what does that make two metres? Compared to most cellular frequencies, I suppose that it is unbelievably low.

Anyway, it sets up a peer-to-peer network between two or more goTennas to exchange data at a slow speed. It doesn't even use the internet. Mostly, it's for exchanging GPS co-ordinates.

From the original article:

The network formed by goTenna is completely off the internet grid, so you’re not going to be surfing the web or tweeting with the device. But goTenna has designed a messaging and location-sharing app complete with downloadable maps that will make it very convenient for people in the middle of nowhere to communicate with another and coordinate their movements.
“It can be used by two people in the Sahara or 5,000 people at Coachella,” Perdomo said. “We’re flexible.”

Hmmm. Doesn't that sound an awful lot like APRS?

Basically, two entrepreneurs have taken the concept of amateur radio APRS and cleaned it up enough to make the messaging and location interface (API) user-friendly. Then they put it on the VHF Business Band and encrypted it so that the 'evil government' can't listen in (wanna bet?), and made it all proprietary.

This is similar to what Garmin did with their "Rino" line of GMRS hand-held radios, only on UHF. Neither of these solutions involve an infrastructure network of digipeaters (beyond the peer-to-peer local goTenna network) or gateways. In both cases, the idea is to keep the packets off of the internet.

While there is software available for hams to use RF APRS packets and display the data on a map, it's not very user-friendly, easy to install, nor particularly portable. It would involve a radio, a TNC, and a laptop. With licensed amateur radio operators comprising less than 0.25 % of the U.S. population, it would be a very limited market for similar smartphone apps to be developed for the purpose. Still, apps such as APRSDroid can be used with an external TNC on Android, though you need to show your licence to get it to work.

The goTenna simply combines the TNC and VHF radio into one convenient (Bluetooth-linked) "stick". It seems pretty clear that either RF power output or battery life (or both) would be severely compromised with this solution. But no ham radio licence would be required, either. It's possible that proprietary goTenna digipeaters will be marketed to solve the problem of limited range, though that's not being planned at the moment.

Imitation is the sincerest form of flattery, as they say. So what's next? UHF SSTV to share photos (wink, wink) without an internet digital trail? RF packet IRC networks to "share files" and "chat" anonymously? Ultrasonic PSK to privately exchange messages in RF-restricted environments? Neighbourhood RTTY networks?  All proprietary and completely unlicensed, of course.

Here's your next million-dollar concept: suppose that there was some way for people to talk to each other, whether they were in their car or at home or out walking the dog, that didn't use the internet or cell network and was free of NSA spying? You could even meet new people, or keep in touch with your immediate family, and it would use RF. No keyboards or distracting text; just normal human voice. Think of the marketing possibilities!