Archive for the ‘aprs’ Category
The old Baofeng HT (UV5R) is the butt of many jokes these days in amateur radio. But right after their introduction, they were the “Xiegu HF rig” of the moment: they mostly worked, were cheaper than many similar products, and hams just had to explore them!
I bought a few, kept one, but gave them to new hams. Heck, I even purchased a case of Baofeng’s to supply the new amateur radio club in my home county of Washington County, GA. They would charge them up, program them for the new repeater, and gift them to newly licensed Techs in Sandersville and there abouts.
What happened to the one I kept? Well, if you have a minute, here it is.
The Jackson MS area had fallen by the wayside in terms of APRS digipeaters. But it really sucked by not having any iGates. A fellow ham who was head of Security at an area hospital installed an iGate serviced by backup power as part of their EmComm effort. That was fine…until the IT team monkeyed with “odd” IP connections and just cut Internet service to it periodically. The turnover in IT kept the Security Head (the ham) busy renegotiating service behind their firewall. So he eventually got them to put it on the guest WiFi sector and it’s been serving the area reliably ever since.
But N5DU and I led the effort to add more digi’s in the greater Jackson area, donating ones to the Vicksburg Club, a tower east of us that the manager (also a ham) gladly installed, a node at a nuclear power plant at Port Gipson, and one down I-55 South near Crystal Springs. But only one iGate to serve them really got in the way of educating the other digi managers to configure the right number of “hops” to effectively get to an iGate.
So I used my remaining Baofeng HT with a small footprint PC (Dell OptiPlex 160 Tiny Desktop, bought for $40 shipped via eBay) and a software modem to create a second iGate in my home (K4FMH-10). As the picture from APRS Direct above illustrates, it’s in the large footprint of the JARC digi installed on a water tower in Madison, MS to the NW of my QTH on the Barnett Rez. (See inset of my iGate’s estimated footprint by APRS-Direct. No, KI5JCL-9 isn’t riding a horse. He just has a sense of humor!)
It’s stored in the bottom of a builtin cabinet in my small library / printer closet adjacent to my 2nd floor office. It’s 3 miles from a nearby APRS Digi maintained by the Jackson ARC (my friend N5WDG maintains their repeaters and other digi devices). And, it sits in the supplied Baofeng charger. For over 2 years, working faithfully. Until it didn’t. And that’s the focus of this story.
The higher power battery is a slim-line model. I thought that would be good for this little iGate-robot. (See the picture on the left.) And it has been.
Bobby KG5TGT later added a 2-way iGate to the Southwest of Jackson. It covers several Digipeaters on that side of town: the JARC’s 2nd digi on a broadcast tower, Vicksburg’s Digi (that N5DU and I donated), and the monster on a tower at the nuclear power plant outside of Port Gipson. FB all the way! Until this happened.
Yep, over a day’s period, the 2 year-old high power battery (Baofeng marketing-speak) hit it’s outer charge limit and expanded several times over the slim size that it was…well, the day before!
All this happened while I was in a recording session for the ICQ Podcast. Unbeknownst to Martin M1MRB and my fellow Presenters, I simply ordered a replacement on Amazon that was delivered in 2 days. The K4FMH-10 iGate was back shipping packets into the APRS network.
The moral? Oh heck. Just check your batteries periodically. While I thought I had, this could have produced a fire. Fortunately, I’m in that small room every day for various things and I look at the iGate system. But this expansion occurred over a 24-hour period. I should take steps to create a more robust iGate unit. But that might mean I’d become Baofeng-free!
Do you have a Baofeng lying around, getting no use? Find a way to put it to some good. But do check the battery from time to time.
Way back in the Wayback machine, when I was working on getting my Technician license (in the 20th century), I recall looking at the frequency bands available to Techs. Technicians had operating privileges for everything above 50 MHz, which looked like a lot of useful spectrum to me. The idea at the time was that Technicians were exploring the new frontier of amazingly high frequencies. Since then, the Technician license has morphed to be the entry level license.
ICOM has a good graphic that shows all of the ham bands and shows the common subbands for various modes. I snipped out the portion that covers the most popular VHF/UHF bands (below). Wow, look at all the stuff you can do! Also, it is 4 MHz of spectrum, big enough to fit eleven 20 meter bands inside it. (Yeah, yeah, the propagation is a lot different.)Speaking of bandwidth, take a look at the 70 cm band, with 30 MHz of spectrum. (Not shown is the 23 cm band, which spans 60 MHz.) The higher you go in frequency, the more spectrum there is.
Most people think of the 2-meter band as just FM and repeaters, but it is much more than that. I copied the 2-meter band graphic and added my own notatation on the various uses of the band.
Much of the band is allocated to FM, which is consistent with the popularity of the mode. I didn’t mark all of the FM segments, so refer to the color coding to see them. But there is much more than FM simplex and repeaters. Down on the low end is the CW-only segment and EME activity (Earth-Moon-Earth or moonbounce). The “weak-signal” enthusiasts tend to use the SSB portion, with the SSB calling frequency of 144.200 MHz. You may often hear CW in the SSB subband and radio hams flip back and forth between the modes depending on propagation. Meteor scatter is mostly done via the WSJT-X mode of MSK144 around 144.140 MHz.
Automatic Packet Reported System (APRS) activity is mostly on 144.390 MHz, using FM-based 1200-baud packet radios. Other packet radio usage is not shown but is usually around 145.01 MHz. The 2m band is very attractive for satellite use, with VHF propagation properties and manageable doppler shift for Low Earth Orbit (LEO) satellites. The downlink from the International Space Station (ISS) is usually 145.80 MHz.
Over time, I’ve used all of these 2m modes mentioned above, with the exception of EME. I am still working on that one and I hope to have a new 2m Yagi installed sometime this year that will enable it.
73 Bob K0NR
I took the dog for a walk today, as you do on new years day. We went down to the beach and then up the headland. Usually I don’t take a handheld with me but today I did, my Yaesu VX8gr which has been up quite a few fells with me and has always been very dependable. Today however I noticed a fault, even though the GPS was on and there was a valid fix the beacon refused to accept the co-ordinates and told me I was at home (I checked back when I got home).
This is a bit of an annoying habit.
A full reset and reprogram didn’t seem to get it to work so I’ll have to search around for a way to solve this. A quick search didn’t reveal users with similar faults. This could be very annoying if I’m out on a fell and using the APRS to report back to Mrs g7kse where I am!
If you are anything like me you have used those little repeater directories and strained your eyes in the process. I use to hate trying to find a repeater to use while I was on a trip. Most of the time, while I was on a trip, the town that I was in didn’t have any repeaters in it, but the next town over did. Maybe it was two towns over, or the third of fourth town that I look at in the directory. Either way, it was a pain in the…well you know.
Bob had the same thinking that I did all those years ago, but he acted on it. He went and digitized all the repeater data that was available and made it into an Android app. It is now available to IPhone, Android and on the web for just a small fee.
RFinder is the official repeater directory of Canada, the United Kingdom as well as 13 other countries. This year the ARRL partnered with RFinder to print the 2017 ARRL repeater directory. This years directory has 10,000 more listings and is the first time that the ARRL has crowd sourced the repeater information. The data that RFinder uses comes from many different places including Repeater societies, club websites and directly from repeater owners.
For more information about RFinder, hear it from Bob himself in the latest episode of the Everything Ham Radio Podcast at http://www.everythinghamradio.com/podcast/75
With Hamvention already on top of us, I figured I’d throw my two cents worth into the mix with everybody else’s. In this episode of the Everything Ham Radio Podcast, we talk about some of the interesting things that are going to be going on at this years Hamvention at it’s new location in Xenia, OH.
DARA teamed up with The Miami Valley Mesh Alliance (MVMA) to setup a Mesh network on channel -2 at 10 MHz bandwidth. The SSID is AREDN-10-v3.
We talk about all of my fellow podcasters/youtubers that are there and what they have going on and where they are at.
Lastly, we discussed some of the interesting forum topics that are going on during the weekend. To listen to the episode as well as check out all the links and further information on the topic, check out the show notes at:
For the past few months I have been having a love hate relationship with a Raspberry Pi Model B and Direwolf. The software runs perfectly well on my Pi3 but makes my other Pi fall over relatively easily. When this is at home it is no problem at all. I just reset and it will restart the software but the trouble is it has been at the clubs QTH. Ok I can log in remotely and deal with it but when it refuses to connect to the internet it becomes a pain. So I was looking for alternative solutions.
I came across the Dorji DRA818v module a little while ago and though that would work. It is a simple module that just needs a PCB and some connections to the Pi. But hang on, there are PCB’s you can already buy. But they don’t have filtering. Now hang on again there are those with filtering too. Now that looks good. Then hanging on for a third time the Sainsonic AVRT7 does it all simply!
So, now there are a bunch of choices for the same module. I’ve ordered a AVRT7 and around 30+ working days later I should receive the new toy.
There are a few warnings about counterfeit Prolific chips and trouble programming. I can see some frustrating times ahead but I’ve never been one to shy away from a challenge. I just hope it’ll be one that can be beaten. I will also get myself a SV1AFN pcb when I get around to it for home / experimental use. Just don’t tell Mrs g7kse!
Whilst we are on the subject I am really impressed with Direwolf. WB2OSZ has produced a really great bit f software that is easy to install on that Raspberry Pi and RTL Dongle you bought that you’re not using. The world can only get better with loads of iGates
This small VHF APRS tracker can easily be improved with some simple measures:
- The 1 Watt of output power is often too little to reach the desired APRS digipeater reliably enough. It is much simpler to improve the antenna than to add an amplifier and it can be done as follows:
- Use a longer telescopic antenna. In the picture I have used an antenna that can be extended from 16.5 cm to 45.2 cm. Depending on how you use the tracker, always extend the antenna as much as practically possible.
- Add an external counterpoise or “tiger tail” of length a quarter of a wavelength. That’s about half a meter. In the picture it is fastened on the antenna’s BNC connector by means of an 8 mm ring terminal.
These simple steps have made my AP510 tracker much more useful.
The post “What it takes to make the AP510 APRS tracker useful” first appeared on the LA3ZA Radio & Electronics Blog.