brainwagon "There is much pleasure in useless knowledge." — Bertrand Russell

31Jan/100

Homemade applesauce…

If you are a long time reader of this blog, you know that it wasn't always about ham radio. It's really about whatever I happen to be thinking about and doing that I wish to share and talk about. Tonight's topic was simply this: applesauce.

I was watching America's Test Kitchen, where they were making homemade "shake n' bake" style porkchops and applesauce. I didn't really feel like having porkchops, but because I've been eating poorly lately (too many restaurants because of visiting son and his wife, and my own visits to my brother) I had a bit of a sweet tooth, and the idea of making some homemade applesauce sounded really good, and much better for me than the ice cream which I've been indulging far too often in lately.

If you buy applesauce in a can or jar, far too often it suffers from a number of problems. It can be made from apples which just aren't very good. It's often far too sweet, with lots of high fructose corn syrup. It can have preservatives or other additives. Often it includes overpowering spice elements like cinnamon. Yuck.

America's Test Kitchen suggested a very simple recipe. Take 4 pounds of apples. Wash them, core them, and dice them into coarse chunks (skin on). Put them in a pot. Add 1/2 a cup of sugar, a pinch of salt, and a little water. Cook for around 15 minutes, until the apples are soft, and then put them through a food mill to remove the skins and even the texture.

They suggested a number of different apples that could be used. For my experiment, I used eight of the Pink Lady variety. They are related to the Golden Delicious, but have a nice rosy color to them that's pretty. Eight of them was about 3.5 pounds uncored. I chopped them fairly coarsely, added a splash of water, a pinch of salt, and just a little sugar (no, didn't measure, but probably less than 1/2 a cup, maybe just two table spoons). I set this covered on medium heat.

After a few minutes, you could smell a cider-like smell, and the apples began to boil and liberate a lot of water. I thought that maybe I had too much water, but after a few more minutes, the apples began to break down and lots of the liquid was reabsorbed. After about 15 or 20 minutes, the apples were soft and smelled delicious.

I don't have a proper food mill, so I just took a potato masher and crushed 'em. Yep, skins still on, but as I mashed them, they lent their rosy color to the mash, and I actually liked the textural element. I added a very small amount of cinnamon, stirred it in, and then let it cool for a couple of minutes.

It was delicious. What's really great is how the fresh complex flavor of the apples really come out. They are sweet, and tart, and clean tasting. Next time I make pork chops, I'll have to make some of this applesauce. I think it would also be good with a scoop of good vanilla ice cream, or maybe with a cobbler like topping of oatmeal and brown sugar and maybe some cold cream.

We don't appreciate these classic foods very often, at least in the way that they used to be made. Thanks to America's Test Kitchen for motivating this delicious culinary experiment.

30Jan/100

HAMRADIOSAFARI.COM

If you haven't had a chance yet, try checking out Jack Dunigan's HAMRADIOSAFARI.COM blog. He's (from his sidebar) the Senior Management Leader of Aidchild Inc., a project which provides homes for children for orphans living with AIDS in Uganda. While that's important far in excess of anything having to do with ham radio, he is also a dedicated radio amateur, and has taken to blogging his ham radio adventure in Uganda. Building antennas, assembling a Tuna Tin 2, making a PTT switch, and even the adventure of getting licensed and (unfortunately) dealing with malaria have all been subjects.

Put it in your daily list of reading. And Jack, if you are reading this, best wishes to your endeavors, ham radio related and otherwise.

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28Jan/100

Crazy Simple 40m Transciever: MOSQUITO Minimalist Transceiver

This 40m transceiver only has around 16 parts, and only a single active device: the ubiquitous IRF510 power transistor which you can even get at Radio Shack. Okay, it's not exactly a complete receiver: they wired it to a PC sound card, and run an SDR application to get receive audio, but still, impressive!

ea3ghs - MOSQUITO Minimalist Transceiver.

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28Jan/103

M1KTA’s QRP ham radio blog: PTO VFO

If you go back through lots of amateur radio designs, you'll find many, many circuits that use the nearly uniquitous 365pf air spaced variale capacitors that were nearly ubiquitous up until about 25 years ago. In the last couple of decades however, they have become like Avatar's unobtanium, seemingly impossible (or at least expensive) to find. One solution to this problem is to use varactors controlled using variable resistors (which are still relatively easy to find) but another interesting technique is to build your own variable inductors. Hence, was born the PTO (permeability tuned oscillator), a nifty little homebrew circuit and gizmo that can provide a variable frequency oscillator. M1KTA talks about building one of his own:

M1KTA's QRP ham radio blog: PTO VFO.

I've had this in the back of my head as an interesting project, so seeing notes on someone building one is inspiring.

27Jan/102

Book Review: The ARRL Antenna Designer’s Notebook by Brian Cake, KF2YN

The other day I was in HRO and scanning for some reading material for the long weekend. I ran across Brian Cake's new book, The ARRL Antenna Designer's Notebook. A brief skim of it showed that it actually covered a couple of interesting antenna types which I had never heard of: the Box Kite Yagi and the Twin C antenna and some brief forays into other topics, including ground planes and small transmitting loops.

About half the book is dedicated to the Box Kite Yagi, which are basically a collection of Yagi antennas which are carefully designed to optimize gain relative to previous state of the art Yagi antennas. For instance, a six element 2m Boxkite has a boom length of approximately 85 inches, and has a gain of approximately 14.6dBi. If I try to make a 144Mhz Yagi using DL6WU's classic long Yagi design and with similar gain, I end up with a boom 427 inches long (almost five times as long). I frankly am not experienced enough at antenna design to understand the tradeoffs involved here, or whether there (say) the box kite is more sensitive to fabrication errors, but reducing the overall boom length to such a dramatic degree is very interesting. He also has designs for interesting dual band designs, such as a small 6m/2m yagi that has around a 7 foot boom. Very nice, and thought provoking. I'm wondering whether an antenna like this aimed toward the moon rise/set positions would enable me to receive JT65 EME transmissions. Very neat.

I'm also quite interested in the "C-pole" antenna design. It's a short vertical antenna which has very good low angle takeoff, and requires no radial system. There was an article about them in QST a while back, but a lot more details in the book.

Some of the more thought provoking antenna design notes I've seen in a while. I am glad I picked it up.

Filed under: Amateur Radio 2 Comments
27Jan/100

Vicacopter

There has been a lot of work in recent years toward making amateur level UAVs. This one is a tricopter, and is completely open source. They claim that it can fly for "under $100 in parts, not including the airframe". Sounds like a very cool project. It splits the computational load between an onboard pic that handles rate damping, PWM of the servos, and sensor capture, and a ground station computer which creates an interface and runs the navigation. Nifty.

Vicacopter.

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27Jan/100

Upcoming Balloon Launch: Arizona Near Space Research

Another one of those nifty amateur balloon launches is scheduled for next Saturday, February 6:

The vehicle will be a 1200g helium-filled latex balloon. The expected burst altitude will be 90,000 feet or higher. The flight is anticipated to last about 2.5 hours from launch to touchdown.
Payload: In addition to ANSR flight computer/cross-band repeater and beacon packages, the balloon train will carry student-built packages containing a variety of scientific apparatus as well as digital cameras to photo-document the flight.

The posting includes links to the APRS tracking pages where you could monitor the flight over the Internet.

Arizona Near Space Research | Promoting science and education by exploring frontiers in amateur radio and high altitude balloons..

26Jan/100

40m spots on WSPR

I've got the RFSPACE SDR-IQ hooked up as a receiver again, and using it to feed WSPR. There is a ton of loud RTTY signals swamping the 40m band in the vicinity of the WSPR signals, but I'm still getting some signals. Here is the reports thusfar this evening:

WSPR_spots

Excerpt

Addendum: Picked up CX2ABP in Uraguay:

Picture 2

Addendum: Overnight, I picked up LA3JJ and VK4YEH among others:

Picture 4

Addendum: Overnight, it appears that my monitoring PC decided to download some security updates and reboot. Hence, logging ceased about 3:15AM local time. I just fired it back up, and got 7L4IOU in Japan and VK6POP in Australia.

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26Jan/104

Hacking with Style: TrueType VT220 Font

I admit it: I'm an old timer. When I first was learning about Unix and C programming, I was sitting in front of a TVI 912 terminal (if I was lucky) or an ADM-3A (if I wasn't lucky) that was connected to a VAX-750. I'm not overly nostalgic, but I do continue to work in much the same way, except with lots of terminals open on a much larger screen, usually with a decent fixed-width font. As a throw back to these older times, I often use green text on a dead black background.

A few months ago, I found a truly nifty font that enhances my sense of nostalgia. It's a very cool True Type font, which is carefully designed to match the old VT220 font, complete with the "scanline" appearance that I remember. It's actually a pretty nice legible font as well. Perhaps you'll enjoy it.

Hacking with Style: TrueType VT220 Font.

25Jan/102

Goodbye QRP-L…

I subscribe to quite a few mailing lists relating to ham radio. A few months back, I decided to give the QRP-L a whirl. Unlike many lists like the EMRFD list, QRP-L had a fairly high NSR (noise to signal ratio), but hey, it's a mailing list. It doesn't take long to skip over stuff that doesn't interest you. It's not worth complaining that people spend more time talking about computer viruses and which sound card interface they use than actual interesting bits of homebrewing and QRP operation.

Today, I unsubscribed not just because it was boring, but because it is whining. Not just whining, but members seem to be piling on the idea that if someone doesn't operate in a particular way that you approve, that they are entitled to maliciously jam your transmissions.

That's illegal. It's also first-order dyed-in-the-wool jackassery.

Goodbye QRP-L. It was nice knowing you.

On second thought, maybe it wasn't that nice.

Filed under: Amateur Radio 2 Comments
25Jan/101

On properly operating a WSPR station…

Anyone who is subscribed to the QRP-L has likely been subjected to a long string of complaints against WSPR in the past week or so. This began with a generic complaint against a "consistent carrier" on 7.040. This rapidly decayed into a long series of rants against WSPR. Since I'm rather more fond of WSPR than the average QRP-L member, I chose to defend WSPR's place in the ham radio universe.

But amidst the general complaints, there are a few points which they make which we should all take to heart. First of all, in the United States we are not allowed to operate automatic beacon transmitters below 10m. This means that you have to be in control of the station, and operate it in a manner consistent with Part 97 regulations. I'm not sure what that really means in the context of this mode, but I suspect that it means that running your beacon all night while you sleep isn't actually legal, as fun (or useful, I would argue) as it might be to see those spots from New Zealand that occur at 4:30AM local time when you wake up and have your coffee. I believe that all hams should endeavor to operate their stations in accordance to regulations, so I think that we as WSPR operators should be at the control point of our stations when transmitting WSPR. I also think that this point of legality isn't adequately emphasized in existing documentation, so new users of the mode may be unaware of this issue, so it would be great if we had a more prominent notice on WSJT's site, and on wsprnet.org.

Beyond simple legality though, I've seen that the QRP-ers have some basis for being irritated beyond the mere legality of this operation. In the last 24 hours, I've logged one particular station who has operated at 100w output power, and for quite a while, was transmitting about 50% of all slots, including many back to back slots. This resulted in spots with a SNR of +5 over distances of 12000km. This isn't a WSPR, it's a rock concert. I think its good to keep WSPR at QRP levels or ideally QRPP levels. And let's keep our transmit percentage down to 20% or less. As WSPR has become more popular (and it has become much more so even in the last few months, with dozens of stations on 40m and 30m) we'll need to reduce the time we spend transmitting to mitigate collisions.

And let's be especially careful around 40m, okay? 7.040Mhz isn't the best choice of frequency, frankly. Lots of old time rock bound QRPers still claim it as their own, and while nobody owns a frequency, we should be courteous to all hams.

25Jan/100

Another checker problem…

I was waiting for sleep to come, and surfed over to the American Checker Federation website. As long-time readers of this blog might remember, I've been tinkering a checkers program together, which I tentatively named "Milhouse" to play checkers. This week's problem challenge was a classic 2 on 3 battle where White is to move and force a draw from the down position:

board

It's late, and been a full day, so I can't really say that I understand this position. But Milhouse doesn't get tired: when I load the endgame database, it immediately proclaim that the position is a draw. What's more is that it identifies two different lines: their website suggests 23-26 as a drawing move, but 19-15 is also a draw.

Without the endgame database, White thinks it is down a man, but with a 25 ply search can't find the draw. In addition to the two moves listed above, it thinks that 23-18 is also almost as viable. But 23-18 is a dead loss, presumably because it allows Red to king both of its checkers. Even with the database though, Milhouse can't seem to find the win for Red in a 31 ply deep search. This seems like a good test case for future improvements to playing with the database.

23Jan/100

XBM80-2 An Experimental 80m CW Transceiver G3XBM

Roger, G3XBM has a terrific blog and website, and is always tinkering things together that I find interesting and inspiring. This morning, I see that he's got a small 2 transistor transceiver for 80m that looks like it could be really fun, and constructed from bits you'd probably find in your junkbox. I like the circuit a bit more than the Pixie, since it doesn't use an LM386, but that does mean that you need a high-impedance earphone because the audio power developed on receive is pretty low. On transmit, it's basically a simple crystal oscillator, tapped on the collector. I'm a bit hazy on exactly how it operates on receive though. Of course, that means that there is an opportunity for thinking and experimentation with LTSpice. Very nifty. I might have to breadboard this one up myself.

XBM80-2 An Experimental 80m CW Transceiver G3XBM.

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23Jan/100

10 more minutes of “The Cuban Lady” on 5.883 Mhz

I was bored, tuning around when someone on the #hamradio IRC channel mentioned that the "Cuban lady" numbers station was audible around 5.883Mhz. I was bored. I recorded 10 minutes of her. Now you can be bored too.

The Cuban Lady, V2A recorded 1/22/2010, around 11:15PM PST

20Jan/101

K6HX QRSS Grabber

For fun, I've got my new RFSPACE SDR-IQ running on my laptop using Spectrum Lab and monitoring the 30m QRSS beacon subband. I enabled its HTTP server, and now have set up a little cronscript to copy its display to my webserver once a minute. You can see an example display below (showing KC7VHS, AA5CK and WA5DJJ) or you can click on the link below, and get the live version on QRSS.info

_spectrum

K6HX QRSS Grabber.

I'm not sure why the frequency display on the right is wrong. Anybody have any ideas? I probably have missed something in the configuration of Spectrum Lab, but it's rather like operating the Space Shuttle...