This is probably old news for some of you, but if you miss having Radio Shack around, Amazon is the new Radio Shack, including all the other electronics parts stores rolled into one.
If you are a regular Amazon buyer, you’ve probably noticed that the Chinese “quick and dirty” module and parts suppliers that started out on eBay have all opened stores on Amazon now as well. Being on Amazon generally means that they have to live up to a higher standard, if that kind of thing kept you from clicking the “Buy it Now!” button on eBay, but I’ve never gotten ripped off by any of them on eBay either.
Anyway, these guys offer just about anything imaginable for the Ham, DIY’er, or even an RF engineer like me. I’m truly amazed at all the parts and pre-made modules you can buy from them. If you have an Amazon Prime membership, which I highly recommend, you can buy just about anything and find it on your doorstep a day or two later, often without tax or shipping charges.
The prices are almost always way better than Radio Shack’s ever were. Here’s just one example: I needed to buy a 2.1 x 5.5 mm coaxial power plug–the type that you often see on the end of the “wall wart” power supplies. Looking on Amazon, I had tons of choices, including whether or not I wanted some with wires already soldered on them and ready to go. I finally chose these:
So, for less than $.60 apiece, I got 10 plugs with wires already attached. No tax charged, and free two-day shipping. Can’t beat that! Stock up for your next project!
There are dozens of videos on YouTube showing how to build your own Bluetooth speakers or boom boxes. A number of them have ready-made Bluetooth radios and audio amps in common. These Bluetooth and audio amp modules are interesting because they are quite cheap (most under $20–see this one on Amazon as an example), fully built and tested, and easy to interface to. You could probably build one of these without even knowing how to solder! It’s a simple matter to fit one of these small BT/amp boards into a box with speakers you’d mount yourself, or even retrofitted into an old plastic-fantastic boom box you have laying around, or maybe purchase for next-to-nothing at a Goodwill store. All you really need is the housing and the pair of speakers. Everything else can go!
For those of you that are old enough, remember the little transmitters you could buy or build that output a fairly unstable signal somewhere on the 88 to 108 MHz FM broadcast band? They were often called FM or wireless mikes. Plug one in, and tune in to it on of your FM radios you happened to have around the house. They worked sort-of OK, but were never very good, and the 9V battery usually went dead in a few hours’ use. In the Bay Area, you also had lots of trouble finding a fairly open radio channel to use. The whole system was, as the British say, kind of fiddly. It was more of a science experiment than anything else..
With Bluetooth, it’s so much easier, and the sound is just light-years ahead of the old analog FM stuff! Most of us carry smart phones with Bluetooth built into them already, so it’s almost trivial to play the music or podcasts on your phone through your car stereo system or an inexpensive set of Bluetooth tabletop speakers. Most of the cheaper BT speakers don’t have such great sound, though. They tend to be small and tinny-sounding, but that’s not Bluetooth’s fault.
Anyway, here are several links to folks that have built their own Bluetooth speaker systems. Maybe they’ll inspire you to roll your own:
Here’s an under-$20 BT dongle that plugs in to any 3.5 mm jack, giving you instant Bluetooth audio for a home stereo system or maybe even a car stereo. This is sold by Parts Express (good company–lots of speakers and speaker kits as well), but there are many similar and cheaper units on Amazon as well:
I found this inexpensive Chinese copy of the venerable Yaesu MH-48 mike on Amazon for $14.99. At that price, even if the mike doesn’t sound as good as the original, you could open it up and pull out whatever replacement parts you need on your original mike, and throw the rest away! Turns out that it actually sounds pretty good. I bought one to try out on my TYT TH-9800 because I’m not too keen on the mike that ships with it. Oh, it’s not horrible, but if you’re going to make a clone of a Yaesu radio, why not clone the mike as well?
That’s basically what this mike it–a true Chinese knockoff, right down to the “Yaesu Musen” small type and logo! It pretty much feels like the MH-48 on your FT-1900, FT-2900, FT-8800, FT-8900 and etc. The only difference I’ve found so far is that the PTT switch doesn’t have the nice tactile feel that the original does. This one’s kinda squishy, but not horrible.
Anyway…if you’re going to try this out on your TYT radio, you’ll be disappointed to find that the PTT button doesn’t work. Yaesu mikes run on 8 volts, and the TYT runs on 5v. So, you have to open up the mike and parallel a 100 ohm resistor across another, then it works fine.
Click on the mike’s picture to go to its Amazon page. For those with TYT radios that might want to try a “real” Yaesu mike, I’ve uploaded a pdf file containing the instructions for adding the resistor:
My geography teacher in High School was a complete bore, but I listened anyway! Most of the kids didn’t. I still got my “A”, but not because of the excellent teaching. I’ve always been a bit of a geography nut, but then my wife would probably add that I’m generally nuts about lots of things–or just plain nuts.
I’ve always found our world, and the people in it (and everything/everyone outside our world, too), to be very interesting and worth study. But that’s just me, right?
I really enjoyed this little puzzle that challenges you to place the countries colored red into their correct spots, turning them green. While you are doing this, however, you are actually learning more than your geography probably tried to teach you in a week of trying.
You see, it’s really tough to project a sphere on a flat surface. Oh, you can do it, but it comes out pretty ugly. Your face, for example, would be mostly unrecognizable if we projected it on a flat surface (such as if you fell face first off the Empire State building onto a sidewalk, but then I digress…).
The main take-away is that most of us look at the world on a flat surface, and land masses are badly distorted in size as you move them away from the middle-center of the map–in this case, around Ecuador. Even if you don’t play the game (try to beat me: 1 minute, 36 seconds), grab Greenland and move it around. Big ol’ continent huh? Let’s see how big you look now, parked next to Brazil!! Oh wait, you can’t grab Greenland just yet. It’s hiding somewhere as a smaller outline. There, that’s your one hint, so I’m giving you a handicap towards beating my time. But really, try grabbing any small red outline near the equator, and drag it out towards the poles. Gets really big, eh?
So what’s the Ham Radio tie-in here? Not a whole lot, except that as hams on HF, we often look at flat maps, when we ought to be thinking more of the semi-spherical world with its interesting signal propagation and what-not. Oh, and this puzzle was linked from one of the guys on our W7DXX.com remote-controlled superstantion email group. There, there’s your ham tie-in. Enjoy the game, and just try and beat me, if you dare!
We all ask ourselves that question now and then when we turn on our radios. I took this snapshot of 40 meters early Sunday evening, May 8th, at 6:30 PM local time or 0130 UTC. You can see lots of activity within the US, and between primarily the US and Europe, as well as Mexico, the Caribbean, and South America. Even if you are not a big DX’er, or even a General class ham, this should be interesting to you.
Looking in the upper left portion of the web page (you can click on the map to go to the real website), you’ll find your navigation buttons to click. Select HF or VHF+ bands, then select an individual band. You can also add in the sun’s greyline, to help illustrate the interesting effects the sun has on many of our bands. Looking at certain times of the day, you can also start to see how busy 40 meters can be in the early evening, and how it often dies out late at night local time. 80 and 160 meters will appear to be dead during our local daytime, but look at how busy they get when the sun goes down! When you look at 160, you’ll also have to remember that it’s pretty lightly-populated compared to 80, because of the large antenna sizes it needs (think 260 feet long for a dipole, or a 130 tall vertical monopole!).
Another thing to use this map for is to look for openings in 10 and 12 meters, as well as 6 meters. We are entering the spring and summer months when, even during sunspot minimums, we get openings on 6 meters, with more activity on 10 and 12. If you are a Tech class ham, 10 and 6 meters should be very interesting to you, because you have operating privileges there. I was surprised to see hams recording QSO’s on 6 meters today, even after dark in their local areas! 6 meters is the magic band–it opens suddenly and acts like a regular HF band, giving world-wide contacts, then shuts suddenly, often to open again between two areas. One day a few years back, somebody on the N6NFI repeater (145.23 MHz in Palo Alto–a busy repeater) called out that 6 meters was open to the Midwest. I was in my Camry at the time (RIP–died in a rear-ender in 2014 on HWY 85). It was my HF through UHF mobile ham station at the time. I dialed up 6 meters on my FT-857, pushed the rocker switch on the dash to shorten my Lil’ Tarheel HP screwdriver antenna to 50.125 MHz, and listened to a bunch of signals coming in like 20 meters during a contest! I only had about 10 minutes until I got to work, but I easily contacted three stations in a row in New Mexico. All were 59+, very strong. And then, after about 30 minutes, the band was quiet again! Lots of fun, though. It’s a bit like a fisherman calling out to his friends that the fish were biting like crazy! We all dipped our hooks in, and started pulling out big, fat ones. Then the school swam away, but we felt victorious for having been there!
Those of you that are new might wonder about all those squares (rectangles, actually). They are called, oddly enough, grid squares. They are 1 degree latitude by 2 degrees longitude in size, and help hams working VHF or satellites to get a rough idea of where someone they are talking to is located. You might hear this on 6 meters during an opening, or on almost any satellite QSO. If you live near me, you are in CM97. In Hollister, you are CM96. If you aren’t sure, check your callsign on QRZ.com and see that it has already been assigned to you, based on the address you gave when you first got your license.
Have fun with DXMaps,com, even if you are not active on HF–yet!
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