Archive for the ‘Amateur Radio’ Category

You seem shorter than I remember…

Tuesday, November 25th, 2008

When you get an amateur radio license, you are issued a callsign. Mine was KF6KYI. This was a “2×3″ call, which means it had two digits, followed by a single region digit, followed by three letters. These are issued sequentially, which means they aren’t particularly aesthetic or short. If you want to spend a grand $14, you can request a different (usually shorter, but sometimes with just some special meaning to you) callsign by the “vanity callsign program”. The shortest “1×2″ calls are fairly rare, so they actually have a kind of lottery system to reassign ones that have expired.

Net result: I am KF6KYI no longer.

I am now:

K6HX

New Morse Paddles

Saturday, November 22nd, 2008

Today I had a few minutes to finally put together this pair of small Morse paddles that I got from American Morse. They have a very nice “milled aluminum” aesthetic that I like a lot. By themselves, they are a little light, and tend to float around a bit, but they include a tapped hole that can be used to secure them to a board. I’ll probably use a little wooden plaque from a craft store, and mount my K1EL keyer on it as well to create a little mini Morse station that I can use with some of the QRP kits I’m building/planning to build. Or, I could simply hook it to my FT-817. It’s got a built in keyer even. Not sure yet.


Addendum: I was still bored while waiting for my wife to show up, so I went ahead and soldered together my K1EL keyer kit, pictured to the right. I only had one real problem: the instructions claim that when you insert the battery, you should hear the dit dah dit (R) through the small builtin speaker. I didn’t. I was confused. I checked the voltages between supply and ground. 3.2v, just as it should. The chip was getting power. I puzzled for a while, then suddenly realized there was a jumper that I needed to install to enable the small piezo speaker. Once I did that, all was well. Now, all I need is the proper cabling and a nice box (Altoids tin?) to mount it in, and I can use it with my new paddles.


Addendum2: Today I hacked a little 1/8″ stereo cable and wired it up to match the requirements of my FT-817ND. I’m a complete rookie at this Morse stuff, but I thought I’d record a quick little video to show how it works, using my Canon digital camera. The audio on this thing is a bit weak, but you can get the picture. I had to hold the key down with one hand because otherwise it tends to walk around a bit, I have a block of wood that I’ll eventually bolt it to.


Short Book Review: Hands-On Radio Experiments

Monday, November 17th, 2008

I needed something to read on a plane trip this last weekend, and a quick stop at Ham Radio Outlet had me leaving with a copy of Hands-On Radio Experiments by Ward Silver, N0AX. Ward writes the “Hands-On” column each month in QST, and this book is nothing more than five years of his columns collected in one slim volume. If you have been an ARRL member and received QST for the last five years, you won’t find anything new, but if you haven’t (as I haven’t) you’ll find a bunch of neat articles, each one of which explains a short, concise bit of radio theory, accompanies by an experiment that you could run with a bare minimum of expense. I am looking forward to doing some of their oscillator and amplifier experiments. I recommend the book for someone who likes to learn things through experimentation.

Addendum: Some of the experiments do require equipment which the absolute beginner might not have (like an oscilloscope, which I still lack), but the majority can probably be done with a decent voltmeter.

Ham Radio

Saturday, November 1st, 2008

Two of my current interests…

E51JD from the Cook Islands

Saturday, October 25th, 2008

The 15 meter band continues to be pretty strong today. I was getting mostly South America, but tuning around, I heard E51JD calling from Cook Islands tonight. I turned on the recorder and got this:

E51JD from the Cook Islands

Cheap Yagi

Saturday, October 25th, 2008

I’ve been meaning to do this for a while: toss together a cheap Yagi antenna suitable for listening to AO-51 on 70cm. If you just google for “cheap yagi”, you’ll find the link to the design. An hour, some 12 gauge aluminum (not optimal, but what I had on hand), a poplar stick, some coax and hot glue, and voila. I have an antenna! Now all I have to do is wait for something to come overhead to see how it works.

Addendum: It works pretty darned good. Maybe just a little worse than my Arrow, but that’s just a guess. I was listening to N6PAA on the QRP repeater on AO-51 just a few minutes ago, and his signal was good and strong.


CQ World Wide DX Contest

Saturday, October 25th, 2008

Well, this weekend is the CQ World Wide DX Contest, one of the larger contest weekends. I tuned up to 15m, around 21.259, and found HC8A booming in. Months ago, my 40m direct conversion receiver was initiated with reception of an RTTY signal from HC8N. Both are stations located on the Galapagos Islands. Nifty. Here’s a link to a brief MP3. You can also hear a Costa Rican station operating on the same frequency for the first half or so, then he moved up in frequency a bit.

HC8A, Galapagos Islands (MP3)

Contest exchanges are kind of boring (well, to be fair, REALLY boring) but contests do bring out large stations with lots of power, and allow you to hear zones of the earth that are largely quiet from inactivity.

First Spot from over the Atlantic via WSPR…

Wednesday, October 22nd, 2008

Today, on wsprnet.org, W1BW announced that Wednesdays would be “Special Activity Days”, and that today’s special activity would be to operate on 20m instead of the more common 30m. Overall, I didn’t get as many spots as I typically get during the day on 30m, but I did manage to get a spot from GW4VBE, which counts as my first cross-Atlantic spot. To celebrate, I created a new WSPR spot map:

I really do need a better antenna.

Ordered a K1EL Keyer…

Monday, October 20th, 2008

My Ramsey 40m QRP rig needs a keyer, so I ordered this nifty one from K1EL. I should be able to install it in a Altoids tin or something similar, and have a nice, fully functional keyer. Then, all I’ll need is a key.

Probably can make a key out of an old hacksaw blade and some scrap.

I’m now KF6KYI/AE

Saturday, October 18th, 2008

Just got back from Pacificon. Had a nice time, and managed to pass the upgrade exam. I’m now an Extra class ham. Bow down and worship me! (Just kidding.) The test was a lot closer than I thought it should have been: I seemed to get a lot of questions that were unfamiliar to me, despite a couple of weeks of doing practice exams. Still, it’s all done!

First SSTV image from ISS

Wednesday, October 15th, 2008

It’s not too exciting, but it’s a start. During a 30 degree pass, I managed to get MacRobot SSTV to decode this partial image. It’s not the greatest SSTV decoder: it seems to miss the VIS preamble almost all the time, and loses sync fairly often when noise interrupts, which when you think of it, is pretty inexcusable. I’m told the various Windows programs are better. But it’s a start, and until I write something better, it’s all I got. I’ll be trying for some more passes later today.

Addendum: During my second pass of the day, the SSTV was off, but we heard the voice of Richard Garriot answering questions (which we can’t hear) but which were very legible in response. It starts out a little scratchy, and there are relatively long bursts of static where we don’t hear the questions, but his answers are interesting. Enjoy!

Richard Garriot Speaks from the ISS (MP3)

Addendum2: Here is a link to a master repository of received SSTV images from the ISS. Check back frequently.

Simple Electronic Keyer

Tuesday, October 14th, 2008

Having completed my little 40m QRP transmitter (pictures to come sometime soon), I was scouting around trying to find the most appropriate keying options. While a straight key is the obvious choice, I can’t help but thin that a little bit of electronics in the form of a keyer would help me make better sounding Morse. There are some excellent choices out there, such as the Norcal QRP keyer and the K1EL keyer, but you can also make a keyer just using some very simple ICs.

Simple Electronic Keyer.

Assembled a 40m QRP transmitter…

Sunday, October 12th, 2008

Well, I was kind of bored, so I decided to tack together a little CW transmitter. I had picked up a little 40m kit from Ramsey Electronics. It’s a really simple kit: it took me about two hours to solder the entire thing together, I fired it up, and it works! I only had two problems: one was a molded inductor which didn’t seem to match what was described in the instructions, but it was the only inductor I had left when I had put all the rest of them in, so I wired it in, and it seems to work, and the other was my fault: I misplaced a bunch of 0.01 microfarad caps, and thought they were missing until i found them under my work mat. It’s actually a pretty nice kit, including a case and all the knobs and panels. It looks pretty spiffy next to my TenTec receiver that I built last year. Now, all I need is a key, and I need an adapter to wire it to my antenna, and… well.. I better get practicing on my morse. Pictures and video to come.

Latest WSPR reception map…

Saturday, October 4th, 2008

This week I picked up a spot from 9V1LF in Singapore, as well as a few other more mundane state side locations. I’ve had reception reports from 95 separate stations, from something like 38 states, so I thought it was about time to try to make a new map.

Addendum: Redid the map, which is bigger, and includes a plot of contours of distance from my home location to points on the map. It also includes an arc to Hawaii, just because it looked left out sitting by itself out there in the middle of the Pacific.

WB5FKC on 40m

Friday, October 3rd, 2008

30m was crapping out after about 2:00AM UTC, and I had heard that Christian, WB5FKC was going to be sending QRSS Morse on 40m, just above 7.0008Mhz, so I tuned down and tried recording some. And, miracle of miracles, I got him:

If you read across (and know morse) you can see that it says (with a bit of interpolation) WB5FKC WB5F.. and then cuts out. He reports using a transmit power of only 50mw, and is almost exactly 1000 miles from my location. The recording covers the time from 10:08 to 10:44 or so PDT.

Addendum: I tweaked around with my FFT settings a bit, did a bit of noise reduction and the like, and managed to get this. If you click on it, you can see that there is a bit of chirp as each dot and dash ramp up in frequency over the four and twelve seconds that each takes, respectively.