News

Remote control and other new toys

     I have been playing with the RTL-SDR, a USB stick receiver with an SMA adapter. It is very cool and great fun. Andy KE5KOF is putting together a program and a series of Play Days to explore these great little—and inexpensive—devices. My latest project is to use a directional coupler (less than $30 from Ukraine) and a wideband noise source (from China, also less than $30) to build an antenna analyzer for bands that I don’t currently have equipment to test. Such as the 23cm band, the 33 cm band and more. I also want to test the various bandpass filters that the club has used to see how well they really work, and test preselectors, Buddipole™ antennas and antenna tuners.

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     Ever been somewhere during one of the great events, such as the 13 Colony Special Event going on right now, without access to your HF rig? That describes me.

     Most Icom rigs (well, those with CI-V connections, probably everything in the last 20 or 30 years) can be connected either directly to a network LAN port and thence to the Internet, or to a nearby computer that is connected to the Internet. My base radio is the capable IC-9100. This radio is the famous IC-7410 plus a VHF radio, a UHF radio, the optional 23cm radio, and the optional D-STAR card. Plus, all the filters I could cram into it.

     I have used it for years with Ham Radio Deluxe, Winlink and other software. As a result, I have a stable connection between my shack computer and the radio, and I’ve made all the usual mistakes—and corrected them (cheap unshielded USB cables will challenge your sanity, for example).

     Icom makes a software package called RS-BA1. I installed this recently on the shack computer, and on my usual notebook computer. I can recline comfortably in my favorite chair, with the cold beverage of my choice (generally ice water) at my side, and work DX or run nets with my computer in the other room!

     My next foray was into the wild world, away from home. This required poking some holes in my firewall, establishing port forwarding rules in my router, and using my DDNS account. And it worked! I was able to operate from several remote locations over various WiFi systems and even over two of my cellular hotspots. I don’t know how Icom managed the latency, but operation is very smooth and full featured.

     I was so impressed that I purchased an RC-28 knob from a guy in Japan. This is the same tuning knob and feel as the radio, with some extra function buttons, and plugs into my notebook computer via USB cable. Now I can tune just as if I was sitting in front of the radio—no funky mouse machinations, just spin the knob.

     This is amazingly cool. I’d be happy to demonstrate, if you are interested, or help if you decide you want to set one up for yourself. 

     I know what you are thinking—why not just use RDP and Skype™? Well, I’ve done that too, and it works, although it is more fragile, and the latency issues are a bit tough.

     My next step will be to try Ham Radio Deluxe and some of the other ham programs with it. I don’t think it transfers I/Q, only audio, but that should be sufficient for many purposes.

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     I recently went with another ham to see a steerable inverted-V antenna. This is very cool. There is a control box to choose 40m or 80m (it’s a trapped V). Then there are phasing loops on a control box you put between the two antennas. The antennas are 40 feet apart, which is a compromise that works for both 80m and 40m. 

     If you take out the phasing loop (by flipping a switch) the antenna radiates as a co-phased array, broadside to the antenna line, with about the same gain as a dipole. If you put in the phasing array it acts like a three-element beam, and there is a reversing switch if you want to radiate in the other direction.

     The guy he bought the antenna from is a very interesting long-time ham. His group participates in Field Day with this antenna and routinely takes the top spot in 1A. We may be able to get him to a club meeting to discuss antennas. I haven’t met anyone as knowledgeable and excited about antennas since Bill Krueger, AE5BK, passed.

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     I purchased an RFinder K1 HT at Ham-Com. Actually, it’s sort of an HT. It’s also a full-fledged Android smartphone. But it does UHF FM and DMR, and (shhhhh! it’s a secret) 2W VHF. The cool thing is the modified RFinder app (you can download and subscribe to RFinder with any iPad or iPhone, or most Android devices, and you can go to their website with most browsers. RFinder is an online, continuously updated repeater directory. It’s easy to set a range (say, 20 miles) and your location (if you are on a tablet or smartphone it will pick it up from the built-in GPS) and it will tell you all the repeaters you are likely to hear. It has filters so that you can select the frequency bands you are interested in, and the app will give you the PL tones, offsets and so forth.

     Bob Greenberg, who runs RFinder, realized that programming DMR radios can be quite a chore. So, he found these high-quality combination smartphone/tablet radios and built an interface to RFinder. What that means is that I can view nearby repeaters from the app, and with a couple of taps send a repeater’s programming information to the radio part and get on the air.

     This works for FM repeaters (receive frequency, transmit offset, PL/CTCSS tones) and DMR repeaters (talk group, color code, receive frequency, transmit offset, and more).

     RFinder offers three different radios - the M1, also an HT form factor combined with an Android smartphone; the P1, an Android tablet computer with UHF or VHF radio module; and the new K1, which is an HT form factor and smartphone.

     I’ve been using my K1 for a month. I was not an Android user prior to buying this device, although I had some experience with it. My impression? This is a very capable device. It takes two SIM cards so you can put it on two different networks. It is sealed and waterproof. It has a very loud speaker. The charger is a magnetic attachment so there are none of those rubber covers to worry about.

     The RFinder software is a work in progress. It works and has some really well-thought-out features. But it needs quite a bit of additional development to be really smooth. Still, I love the ability to just look up a local repeater, tap the screen and be on the air. None of that old setting the VFO then all the parameters then saving to a memory. That’s so last century, although it is the way every other radio I have works.

     It’s a good phone, too. I haven’t switched from my iOS device yet, and I’m not sold on Android, but it is a very intriguing device. 

     See it at any Hams & Eggs!

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     Another radio I bought at Ham-Com is the TYT UV-380. This is the same form factor as the popular MD-380 which is a single band DMR Tier II / FM HT.

     I have two of the MD-380s (long story) and I quite like them. I also have a Connect Systems CS-750 which I like better, and a TYT MD-2017 that I’ve never come to love. The MD-2017 is a dual-band dual-receive, so it’s very comfortable. It just doesn’t resonate with me. And I have some kind of a Batwing (Motorola) DMR radio that I don’t like at all.

     Think that’s enough DMR radios? That doesn’t even include the RFinder K1.

     I think, if I like the UV-380, that I might sell the Motorola and both the MD-380s. Also, the TYT MD-2017. Might keep the CS750 or not. I need to get down to a management number of DMR HTs. I’ll have a review of the UV-380 soon.

     73 – Kevin N5KRG