Posts Tagged ‘Soapbox’
We Need a Better UHF Connector
The venerable UHF connector was developed in the 1930’s. It has withstood the test of time and for the most part is a good connector for HF and VHF applications in amateur radio. It’s fairly inexpensive, has somewhat intuitive assembly, and is mechanically robust. From an RF perspective it’s not bad at HF and VHF, but despite the UHF name it exhibits an impedance bump at UHF frequencies and is usually avoided for UHF applications.
The UHF connector suffers from two problems, in my opinion. One is that it’s not weatherproof. You absolutely, positively should not have a UHF connector outdoors without weatherproofing. If you do not weatherproof it, you will have water intrusion into the connector and probably into the braid of the coaxial cable. Weather. Proof. It. Connectors like the N connector (a very common connector in commercial RF applications) which sports rubber gaskets on the mating surface and within the body of the connector are weatherproof, although it’s still advisable to use weatherproofing with the N connector.
The second issue is the difficulty in soldering the braid. The holes in the body of the UHF connector expose the ground braid and you’re supposed to solder through these holes to make a positive connection between the braid and the connector body, and provide mechanical strength and stability. Some folks pre-tin the ground braid before inserting it into the body, others do not. You need a high wattage iron to do this properly and the heat required can melt the dielectric in the process. I think many people don’t solder this well and some avoid doing it at all.
K3LR demonstrated an alternative method of soldering the braid to the PL-259 in this video:
I’ve tried this technique and for the most part it works. (I prefer to use heat-shrink tubing around the exposed soldered braid.) However, as you can see from the video it’s not pretty as it requires increasing the diameter of the dielectric with electrical tape, and there is not a snug fit between the connector body and the soldered braid and the coax jacket. This technique in my opinion does provide a better braid electrical connection than most mere mortals can accomplish using the proper solder hole method, as the connector is intended to be used.
I think a PL-259 connector needs to be designed for this technique. The body of the connector should have a smaller inner diameter in order to fit the diameter of the RG-213 dielectric. The outer part of the connector body where the braid is soldered to it could be of a smaller diameter as well and perhaps have a gnarled surface in order to promote better adhesion of the solder. I would like to see some sort of rubber gasket employed with the threaded sleeve for some weatherproofing, however I can’t think of a good way to implement this without affecting the electrical connectivity to the body.
Unfortunately I’m more a software guy and not very good at fabricating metal parts. Someone with manufacturing experience could probably design this connector and perhaps make a small fortune. It’s problem waiting to be solved.
Go To blazes
Is it just me or do you also get irritated when you see or hear someone abusing the term “go to”? As in “The Buddipole is my go to portable antenna” or “G4ILO’s Shack is my go to website for interesting articles about ham radio”. Okay, I made the last one up.
What are they trying to say? That the Buddipole is their preferred antenna or mine is their favourite website? If so, why don’t they just use the perfectly good words that have existed for years to say so?
Who started this? I think I first saw it in a computer magazine about a year ago. Journalists are responsible for spreading many linguistic abominations. I should know. I was one.
I assume that this is an Americanism which has recently crossed the Atlantic but I have no evidence to back that up.
Is There An App for That?
We’re hearing talk these days of the “Post-PC Era” when devices like the iPad, tablet PCs, and smartphones along with cloud-based applications will ultimately replace the PC. I don’t totally buy into this as these devices don’t have the form factor or horsepower to replace the PC, at least in business environments. I do think that the venerable tower PC, outside of gamer circles, will die. It used to be standard to select a tower PC based on the number of expansion slots and bays, and it was once common to upgrade processors for more horsepower. Those days are gone and more people are using one-size-fits-all laptops or appliance-like desktop machines, and when they’re three or four years old they’re tossed out for the latest model that can run Microsoft’s latest OS and office suite.
For over the last 15 years, when you bought a PC you by default got Microsoft’s OS, Windows and usually Microsoft Office or Works. This symbiotic relationship has been dubbed “Wintel”, symbolizing the combination of Windows and Intel-based hardware. Of course Linux has made inroads over the years but despite what Linux advocates say, it’s never passed the philosophical litmus test, being able to be run by your grandmother. It continues to be the darling of techies’ desktops and runs the Internet behind the scenes.
With applications heading to the cloud and developers needing to support multiple devices running different operating systems, applications are more and more running in virtual machines such as Java rather than on the bare OS. HTML 5 is supposedly going to revolutionize web applications, bringing functionality that was previously limited to Flash applications into HTML, an open language that is universally supported.
Amateur radio in my opinion has always had an odd relationship with software, that somewhat has its roots in the mindset of 1980′s DOS PC computing. It wasn’t until the early 2000s that some of our most widely used logging and contest programs offered Windows replacements of their DOS ancestors. Our free software authors never quite embraced open source, opting more for free-as-in-beer / freeware. Nearly all notable amateur software is Windows/PC based. There is some software for Mac and Linux, but it’s more a novelty. I’ve found Linux ham radio software, especially logging programs, to often be someone’s experiment with making a database frontend rather than a concerted effort to build a major software application, like Ham Radio Deluxe or DXLab. I know this will raise the angst of Linux users, but if you want to run amateur radio applications with full functionality, it’s tough to not use a PC running Windows. I’ve tried about five times to switch to Linux in the shack and gave up. I would love to buy a Mac, but I would still need a PC to run my amateur apps.
There is a paradigm shift in software coming. The PC/Windows world is coming unseated. It’s not going away, but it’s not going to be the default “no-brainer” choice that it used to be. While we have many fine commercial and free software offerings, we’ve failed miserably in making cross-platform applications. Even our networks like Winlink, D-STAR, IRLP, and APRS are vertical “silo” applications, some tied to specific OSs or hardware, or just outright ignore open standards.
Enter the Raspberry Pi, a very inexpensive single-board computer that is for supporting economical computing in third world countries. It’s quickly turning into the latest geek fad. Never has such a small board had such computing power at such a low price, and despite being a full-fledged computer it may very well displace the popular Arduino on many experimenter’s benches. It should be a very hot commodity in amateur radio as it’s cheap and open, and ideal for hardware hackers like us. Here’s the kicker. It has an ARM processor and it can’t run Windows. The best programs we have can’t run on this device.
I don’t see the PC world ending very soon, but I have to question at what point we’re going to start sacrificing some opportunities due to our lack of cross-platform software and systems. In the past when considering software compatibility, one used to ask whether you ran a PC or Mac. Today you hear questions like, “Can I get that in my app store?”, or “Does it run on Android?”
Post-post Thanksgiving Leftover Leftovers
Another Notcom opt-out
A few weeks ago the European Union’s Frequency Management Working Group agreed a harmonized specification for Citizens’ Band Radio across Europe to include AM, FM and SSB modes. It will now go to public consultation before being passed to national governments to become law. However Ofcom, the radio regulatory authority in the UK, is expected to live up to its nickname of Notcom by saying “no” to allowing AM and SSB, claiming there is a potential for harmful interference to other services. How absurd!
Now some readers may be wondering why a ham radio blog is concerning itself with whether CB users should be allowed to use the AM and SSB modes. After all, if they want to use those modes they could just get a ham radio license, surely? The test is so easy even a child could pass it, and many do. So what’s to complain about?
But that isn’t the point. The point is this is one more example of how we in Britain always seem to get the mucky end of the stick when it comes to European legislation. We’re told we can’t opt out of European human rights law that seems to attach more importance to the rights of criminals, rapists, murderers and paedophiles than their victims. But when it comes to something as unimportant as giving a few hobbyists the right to use the same modes as their counterparts across the North Sea, opt out we can. Are we in Europe or aren’t we?
If allowing CBers the use of AM and SSB isn’t a problem for the rest of Europe then it isn’t going to be a problem in the UK. If there was “a potential for harmful interference to other services” then that would surely have been proven by now, since there are plenty of people illegally using SSB on 27MHz already. How many people have been caught and prosecuted for using SSB on 27MHz? Hint: it’s a very round number. And if there is a risk of harmful interference to other services from allowing people to use 12W of SSB on 27MHz, why is there no risk from allowing hams to use 400W a few hundred kHz higher?
There is no sound basis for preventing British CBers from enjoying the same frequencies and modes as their counterparts in the rest of Europe, just as there is no sound basis for restricting the use by British radio amateurs of digipeaters and internet connected nodes. It is about time we had a more open regulatory system in this country so that radio users cannot be denied something for false or risible reasons.
Charles M0OXO laments the fact that England is 334th in the list of the most wanted 338 DXCC entities, in other words the fifth least wanted. Isn’t it a sad waste of a hobby not to mention the vast sums of money people spend on equipment and antennas if the main interest in making a contact is just to be able to tick off a new country? I guess that’s why I find DXing and DX blogs boring. I’d rather read about what people are building, new things that they are experimenting with or how far (even if it isn’t all that far) someone manages to work with a peanut whistle.
In contrast to my giving up the frequency for a DX station while in the middle of a “run” during a contest (as I recently mentioned), I heard a particularly bad bit of operating on last Sunday while trying to work Bob, VP8LP in the Falkland Islands. I’ve worked Bob before on several bands but needed a contact from him on 15m. He had an excellent signal and was steadily working stations, the vast majority of which were good operators, standing by when Bob was working another station and not responding when Bob wasn’t calling them. (Please see my post about The DX Code of Conduct if you haven’t already.) There was, unfortunately, one exception to the “good guys” on the frequency.
As Bob was steadily working the pile, a ham started calling K7NRA on the frequency. After he did this once or twice, assuming that perhaps he was unaware that there was another station on the frequency, I responded to him and said that the frequency was in use and gave my callsign. (The other ham was using his callsign, or what I presume was his, though I neglected to note it. While normally I don’t like to “pick on” people in a public forum, what was going on was heard by dozens of other hams, and if I could remember what it was, I’d post it here.) The other ham said “Well, there’s supposed to be a special event for K7NRA on this frequency and I’m going to call him, this is his announced frequency”.
It was pretty clear that the guy calling wasn’t hearing K7NRA, and aside from that fact that he refused to stop interfering with an active frequency, his general technique was awful. He was calling “blind” (meaning he didn’t hear the other station), and kept calling “CQ CQ CQ CQ CQ CQ K7NRA”, which doesn’t actually make a lot of sense. CQ generally means “calling all stations”, thus saying “CQ K7NRA” means “calling all stations with a callsign of K7NRA”; by definition there will only be one. There are exceptions to using a “directed CQ”, such as when calling “CQ DX” (looking for any DX station) or “CQ NJ” (looking for a station in New Jersey), but proper procedure when calling a particular station is to simply call the station. If I were to call that station, I’d say “K7NRA this is K2DBK” or, if K7NRA was listening for other stations, I would likely just give my callsign only.
Several other stations responded to the caller (some more politely, and some, unfortunately much less so), and he refused to move, insisting that he had “as much right to the frequency as anyone”. Unless he had an emergency (which clearly was not the case), what he said was not true. The FCC rules governing the amateur radio service state that nobody can “own” a particular frequency (including by “publishing” use of a particular frequency at a particular time), and further, if any frequency is in use, with the exception of use in an emergency, nobody is required to relinquish the frequency for another station. Thus, the caller was not only wrong, but he was violating the rule that says “No amateur operator shall willfully or maliciously interfere with or cause interference to any radio communication or signal.”
The guy would not give up, and continued to attempt to call K7NRA repeatedly. The worst of it was when one station was speaking with Bob, and was showing ham radio to a young Boy Scout for the first time. All the others stations on the frequency patiently stood by while Bob spoke with the youngster, all except the guy calling K7NRA, who simply wouldn’t stop. Several hams were telling him (in language that probably violated another part of the FCC rules) exactly what they thought of him, to no avail. While this was happening, it occurred to me what a terrible impression this was making on the young Scout. Is this how we want to entice others into our hobby?
After the contact with the scout was over, Bob, who could hear the guy calling the K7 station, finally said “The station calling CQ, this is VP8LP, please go ahead”. That did the trick, the station stopped calling. Bob called several more times with no response, and finally said “well, I guess I’ve figured out how to shut him up!” and went back to working the pileup.
I would like to say that Bob’s comment had a permanent effect, but unfortunately that was not the case. The caller kept coming back, Bob would respond to the “gentleman calling CQ”, which would usually shut him up for a while, and so on. This went on for a while, with the occasional argument back and forth between the guy calling K7 and others on the frequency, until finally propagation changed enough that he was no longer heard on the frequency.
After this was over, I did a little research to see what “special event” he was talking about, since an initial check of the spot clusters didn’t show any activity for K7NRA. After a little digging I discovered that in fact the Yavapai Amateur Radio Club was, in fact, doing a special event to celebrate the “birthday” of the NRA, as described on their website. The frequency occupied by VP8LP was also one of the frequencies advertised (21.355mHz), but what our caller failed to notice was that the event was scheduled for the 17th of November, not the 14th of November, when this all occurred. This caller was not only wrong from a legal and ethical standpoint, he managed to get a lot of people annoyed at him by trying to work an activity that wasn’t even happening. As they say, you can’t outlaw stupidity.