I finally finished the Survivor. Truthfully, I thought I finished it over two weeks ago, but I didn’t take it to the field with me for QRP to the Field this year like I planned because, well, my plans changed. I still went out for QRPTTF, though, which is what counts. I picked up the Survivor again when I got back, ostensibly to make sure it was all ready for use. And it’s a good thing I did–it was definitely not working right.
Category Archives: The Workbench
Survivor: Halfway Home
In a previous post I told you about my purchase of the Survivor 75-meter SSB/CW rig from Hendricks QRP Kits. I’m taking a “build a little, test a little” approach to building this kit, having a great time and learning a bunch of stuff. I’ve been making some notes and adding them to my site. If you’re interested, here’s the main page for those notes. So far I’ve built up the voltage regulation, VFO, BFO, TX/RX switching, tune mode oscillator, and the balanced modulator. My goal is to have this thing completed and ready for QRP to the Field on April 27th. If this is the kind of thing that interests you, check back every few days for updates.
The Survivor 75-meter SSB/CW Transceiver Kit
So, it’s been quite a while since I did any significant electronics construction. The reason is probably that it’s been a while since a new kit has come along that interested me enough to want to build it. Sure, there are plenty of ham radio kits out there, but I’ve built plenty of CW transceivers and really don’t feel like I need another one. But when Doug, KI6DS announced a new SSB/CW transceiver kit over at QrpKits.com earlier this year, my interest peaked. Dubbed the “Survivor,” it’s a fairly compact but usable rig for the trail. I decided to take the plunge and placed my order, and I’ve just begun the building process. I’m documenting the build as I go, trying to learn a few things about its design along the way. You can follow along if you’re interested:
I’ll be adding to the content as I get farther along on the build. Comments and corrections are always welcome!
USB Digital Setting Circles Kit!
FAR Circuits has just released a kit for a USB version of my Digital Setting Circles project. The USB version relies on the FTDI TTL-232-5V interface cable as shown in a previous post. A complete writeup is now included on my USB Digital Setting Circles page. Here’s the schematic for this new kit:
The kit is much simpler than the serial version–the pull-up resistors were eliminated, the oscillator replaced by a crystal, and a MAX232 chip is no longer needed. The board and encoders are powered by the USB port, too, so no external power supply is needed. The kit includes all the components, including the programmed PIC chip, but does not include the TTL-232-5V cable. The cable must be purchased separately and is readily available from Mouser and Digikey, for about $20 plus shipping.
This kit should work great if you want to run your digital setting circles straight through the USB port of your laptop. However, if your goal is to use a bluetooth connection between your computer/PDA/smartphone and the board, then the serial version of the kit is the one you want to use. Furthermore, this USB version really isn’t adaptable for use with a smartphone or PDA–the TTL-232 USB cable needs to plug in to a PC in order to work.
Bluetooth Adapters for My Digital Setting Circles
I was finally motivated to get my hands on some Bluetooth hardware so I could figure out why my latest ASCOM driver wouldn’t work with Bluetooth. I found mine at U. S. Converters. I needed two–one that would plug into a USB port on my notebook (I bought model BLDONG for $9.99), and one that would plug into the serial connector of my digital setting circles interface (BT232B for $45.00). The BT232B serial Bluetooth adapter also requires a gender changer because it has a female DB9 connector just like my DSC interface, so I bought 10GC-D1 for $7.99, too. I know that AirCable sells this kind of stuff, too, but U. S. Converters seemed a little more economical.
Now it was time to get it all hooked up and functioning.
Field Day: Doing Handsprings Into the Past
The hams among you know that ARRL Field Day, held the last full weekend in June, is fast approaching. A few of my ham buddies and I usually try to pack up our QRP gear and head into the forest or to the top of a local peak for a weekend of sleeping on the ground and seeing how many contacts we can scare up with just a few watts of power and a wire thrown into a tree. This year I’m trying to get a head start on preparations. I’m planning to take my four-band Elecraft K1 with internal battery pack and run off lithium AA’s for the entire weekend. My antenna’s going to be an old stand-by, a half-size G5RV hung from the highest tree I can find. My K1 has the internal ATU and it’ll tune up the G5RV with no trouble, so I’ll be able to work 40, 20, and 15 meters. I even decided to dust off my old mouse paddle–a computer mouse modified so that the left and right mouse buttons act as the dit and dah paddles (you laugh, but it works great because it’s easily managed with one hand–no need to hold it with the other hand or anchor it to something).
The G5RV Returns
If you’ve read my past posts here about my antenna projects, you know that I live in a covenant-restricted neighborhood that supposedly doesn’t allow outdoor ham antennas (at least none visible from the street). Thankfully, there is no homeowners association or dues that support covenant enforcement, and none of my neighbors had thus far even mentioned the short vertical antenna I built and installed in my back yard.
Up until now, I hadn’t really given that antenna a good workout. But last weekend was Field Day, and this year I had to settle for working Field Day from the shack. Sadly, I was disappointed by my antenna’s performance. Although I managed to work 50 QSOs in four or five hours, I struggled to hear and contact other stations, even when running 100W. The noise level was very high, and signal levels were underwhelming. I worked only two SSB stations, the rest being CW contacts. It was time to rethink my antenna situation.
Soldering 101
For a surprising number of folks, my Digital Setting Circles project is their first introduction to electronics construction techniques–mainly, the art of soldering. If you’ve never seen it done correctly, soldering can be an intimidating prospect. Someone asked me the other day whether there were any YouTube videos of someone constructing my project (none that I know of). That got me thinking–there must be plenty of “how to solder” videos around. So I checked, and sure enough, YouTube has quite a few of them.
Doin’ the Lindy
The parasitic Lindenblad, that is. I wrote in a previous post about how I was gathering the parts to build the parasitic Lindenblad antenna for 70 cm that appeared in an article in the February 2010 QST magazine. Since then, I’ve actually managed to build one of these beasts, and for what it’s worth, it even looks like the one in the picture in the article. My first trial with it on a good pass of AO-51 was less than impressive, though. For this trial, I used my Kenwood TH-F6A connected directly to the antenna with a three-foot section of RG-8X coax (to minimize the effect of feedline losses, which can be appreciable at 70 cm). There were moments when I had good copy on the satellite, but they were few and far between. I was a little disappointed, but I wasn’t ready to give up yet. Knowing that the antenna, being more-or-less omnidirectional, didn’t have much gain (especially compared the the handheld Arrow Antenna yagi I’d been using), I wondered if a preamp might be necessary.
As if “Parasitic Lindenblad” Isn’t Funny Enough
A few weeks ago I posted about a new Chinese ham radio satellite, and mentioned a couple of satellite antennas I was considering building. Just a few days later I found the latest QST magazine in my mailbox, complete with an article about (you guessed it) another ham radio satellite antenna project! This one, by AA2TX, describes an antenna he calls a parasitic Lindenblad (here’s a link to an AMSAT article). The antenna, for 70 cm, is right-hand-circularly polarized with an omnidirectional radiation pattern. This makes it well-suited to amateur satellite applications. I liked this design better than some of the others I was considering, so I decided to give it a whirl.