Archive for August, 2007
Sunday · Popularity: 25% · ham news
I don’t know how many people actually use Google Alerts (I am sure it is millions), but for those who don’t, you can find some real interesting and sometimes strange stuff on your topics of interest, along with many other beneficial aspects of the alert system. All in all I probably have more than 50 google alerts to keep up to date with indexed items like my blog, new trends in amateur radio, my name search and so on.
The information is much differently than a reader, like Google Reader, but since it is an email with a little blurb on the new found alert, it is a similar concept, except in email form. Instead of the user finding a site of interest and adding the rss feed to their rss reader, they find a topic of interest, then have Google go get it (with various optional settings).
You just type in the search term you want, just like when you Google something, (including special character searches, which I love) and whenever Google’s spider indexes the term, it finds a match, and boom, you have an alert.
Today, this was the title of the alert for my heading “amateur radio” blog (see screen shot above). I didn’t really want to put the text of the alert in this post, but you get the idea from the screen shot. The article itself was detail oriented (approved for all audiences), but the quote from Wired read as:
The GPS unit uses APRS (Automatic Packet Reporting System) a system which uses amateur radio frequencies to send data, which, ironically, was first developed at the United States Naval Academy (all the nice girls love a sailor).
The shoes are a concept right now, albeit a working one, and can be tried out at the Gallery Aferro in Newark, New Jersey in September (15th, 22nd, and 29th). Mens and women’s sizes will be available, and orders will be taken for custom builds.
information and photo above of shoe: http://blog.wired.com/gadgets/2007/08/gps-alarm-shoes.html
I would like to know a little more about the technology that went into the shoes, like how they are able to transmit without using a call sign without being a licensed radio operator (I assume that a shoe can not be a licensed amateur radio operator). There are FCC statements for frequency use that allows radio controlled planes, RC cars, and similarly controlled machines, to operate on ham radio frequencies without a license, but most will still post their call sign on the side of the plane if they have one. I don’t know that much about RF tags that retailers use on everything, but I am fairly certain they don’t use amateur radio frequencies.
Of course, it says it is using APRS (Automatic Position Reporting System), a system developed by WB4APR which, according to his website, “uses amateur radio to transmit position reports, weather reports, and messages between users”, and all those users are amateur radio operators (as far as I can tell anyway).
I am sure the inventors of these shoes are aware of all the frequency implications and how it can and can’t be used, and I am by no means any expert on the subject at all, I am just interested, as a licensed amateur radio operator, how the technology (and shoes) move from mainstream over to amateur radio use.
For those who know a lot more about packet radio (and APRS) than I do, which wouldn’t be hard, I would love to hear your comments. 73, KI4WLR
Friday · Popularity: 7% · equipment
I just got my first HF receiver, a Lafayette HA-800B, on loan from K4GR (thanks very much), and I can’t wait to get a good dipole antenna constructed and put up so I can listen in. I don’t know that much about the HA-800B but I am learning as fast as my fingers can turn the knobs through the bands. My current shack, as of this writing, only consists of VHF/UHF type equipment, I don’t have any “real” HF antennas in use at the moment, so the first thing I wanted to do was run out and put up an 80 meter dipole antenna, or anything to get that S-unit needle bouncing around with the sound of call signs and CQ’s. Of course, I just ordered the The ARRL Antenna Book
and since it has yet to arrive, I had to improvise.
What I did do for the sake of time was try to put up a random wire antenna (*def) that was fashioned from a trailer wire lighting set, which I had sitting around in a box of saved “wires of potential”. This kit consisted of a single 25 foot, four wire insulated (about 12 AWG) set, with a standard trailer connection and a small white ground wire on one end (both of which I quickly hacked off with my knife) and a clean factory cut at the other.
*When it is not practical to have a 1/2 or 1/4 wavelength long resonant antenna… a random wire antenna can be used. A random length of wire attached directly to the receiver, put out in any manner possible. This antenna is not intended to be resonant on any particular frequency but should be resonant at some frequency. It is a multi-band antenna and the radiation pattern is very unpredictable, but will work with varying results. [ARRL General Class License Manual 2007; C6, P6-6]
Not having done this before, I wasn’t quite sure what the “correct” way to run this new fangled antenna was, but I quickly figured out it doesn’t really matter. You just need to try something, anything, and if and when that doesn’t work you can just try something else. So, standing on the roof, in our 100+ degree afternoon, I grabbed the four wire set and began to seperate it into 4 individual 25 foot wire sections. I saved one wire for a ground (sounded like a good idea), and stripped off the insulation at the ends of the other three wires with my wire cutters and proceeded to splice them all together into a perfect looking green and yellow 75 foot random wire antenna that any homeowners association would be proud to display.
I thought I should do a quick tape job on the spliced wires and I just happen to have this new weather and heat resistant type of electrical tape I had won as a door prize from our club meeting (the EAARC) the day before and just knew I would have a use for it soon when my number was called that night. So, I pulled out the new roll that had now heated up to about 125 degrees and proceeded to roll out some, now tape goo, around the spliced wires and wallah, a completed antenna.
I curled up the 75 feet of wire like a rodeo rider with a rope, and from my position on the roof, sweat dripping profusely now, tossed it up into the adjacent tree to get that good antenna height I knew would make the difference. After a few tries it wrapped around a branch like a fishing lure, and not where I wanted it to stay. I gave it a little yank and my tape goo released its grip on the last 25 foot section, and I now had a 50 foot random wire antenna. No problem I thought, the last section was green anyway, blends right in with the tree and probably wasn’t resonant at a good frequency anyway. Another toss and it was good enough for the time and temperature of the day and now it sits at 30 feet or so resonating and radiating.
The second thing I tried to do after I got home with the radio was to look for a manual for the Lafayette, and so far, no luck other than ones that have been scanned from the original manual, and now offered for purchase (I don’t have a problem with this at all, I just didn’t feel like buying a manual for a radio I was not going to keep). Without a manual I took a visual inventory of the knobs and switches [dial cal, tuning, cal on/off, anl on/off, ant trim, band sel, rf gain, volume, fine tune, and function] and proceeded to flip through the squeal of white noise and high pitched whines.
My dog started howling from the high pitched whines coming in and out as I spun through the bands. Beyond that, I heard lots of loud squalls of white noise in between the whines but no recognizable audio at all. Guess it didn’t work? What else was there to do. Oh yeah, shoot off an email to my Elmer and find out what went wrong. I explained the whole setup and process and he said, sounds good, you should be able to hear something… anything. So I went back and tried again, turning the knobs with both hands like some submarine operator setting coordinates for a launch and then I found that the slower I moved the more the whines turned into Charlie Brown’s school teacher.
Success at last I thought, and that was good enough for my ears (and my dogs ears) for the day. I don’t know what most of the knobs do, but I am learning, and I am told somewhere on there a BFO knob should appear for using the SSB/CW function but at this point I haven’t a clue where.
Anyone that owns an HA-800B I would love to hear from you, especially if you have a manual.
73, KI4WLR
Tuesday · Popularity: 6% · satcomm
Tonight the International Space Station (ISS) will be visible with the naked eye, and due to its brightness, should be easier to spot and show more detail than it often does. The Space Shuttle Endeavour, STS-118, un-docked from the ISS for an early arrival due to hurricane Dean, so the observation will be only the ISS, not the scheduled ISS and Space Shuttle together. When viewed with a good pair of field binoculars you should be able to see some detail or shape of the ISS with its solar panels extended out.
The data listed below is only good when viewed from our location (Auburn, AL) or within a few hundred miles of our location, but there are many programs and look-ups to find your local time data (see below).
The graphical 3-d image of the horizon to the right (click image for larger view) shows how to locate the ISS in your part of the sky (image credit: (RSIS)/NASA) by degrees in elevation and the approach and departure pattern for the given data for the viewing. Again, the pass details shown below were taken from a calculation for our location (32.6042°N, 85.4583°W) and date from heavens-above.com and the actual viewing data listed below can be seen directly from their site here. The forecast from NOAA for our area (here) for tonight also looks good with clear skies.
The sky chart shown below is like a star chart you use to use as a kid. the chart’s east and west are not backwards, when you hold it up to the sky, over your head, to the north, it aligns up properly for viewing. To print out the chart below just click on the link, then click on it again to bring it to a blank page and then print the chart.
Pass Details
|
Date:
|
Tuesday, 21 August, 2007 |
| Satellite: |
ISS |
| Observer’s Location: |
auburn, al usa (32.6042°N, 85.4583°W) |
| Local Time: |
Central Daylight Time (GMT - 5:00) |
| Orbit: |
336 x 347 km, 51.6° (Epoch 20 Aug) |
Sun alt at time of
max pass altitude: |
-19.2° |
Time Data
| Event |
Time |
Altitude |
Azimuth |
Distance (km) |
| Rises above horizon |
20:49:33 |
-0° |
314° (NW ) |
2,141 |
| Reaches 10° altitude |
20:51:34 |
10° |
315° (NW ) |
1,300 |
| Maximum altitude |
20:54:11 |
70° |
325° (NW ) |
368 |
| Enters shadow |
20:54:11 |
70° |
325° (NW ) |
368 |
Amateur radio operators often use a satellite acquisition software to determine when and where a satellite will be to make contact through one of these satellites using amateur radio equipment. One of the popular satellite location sites for ham radio operators is AMSAT, which will also give you tracking data by just entering your latitude and longitude. Other sites for satellite viewing are:
If you have a favorite site for viewing time data please leave a comment below. I am sure there are several more than just the ones listed above, those are just the ones I use. 73, KI4WLR
Sunday · Popularity: 7% · photography
For those amateur radio operators that are also photographers this post is for you. What does it have to do with ham radio, well not much, but I can tie my photography and radio operations together, just see the previous posts, or my upcoming posts on antennas and equipment.
I have now posted an update to the Sports Photography section that includes more gallery images of college sporting events, mainly from Auburn University athletic events, like swimming, basketball, and gymnastics. Just click the above link to view the images.
Each photography section will be updated with new images pertaining to each gallery, including several amateur radio gallery images. Photography can play an important part in ham radio from documenting images for building new radio antennas to emergency communications operations during a storm or natural disaster.
When you are preparing your radio equipment to go mobile, don’t forget your camera. Even if you are not a professional or have any formal training as a photographer, images from the field can be very valuable after you have returned home and can’t quite remember those vivid details of how that yagi looked or how those dipole antennas went up. 73, KI4WLR
Friday · Popularity: 7% · ham news, weather
Hurricane Dean has now been upgraded to a category 4 hurricane and is headed for the Gulf of Mexico. Several amateur radio nets have now been activated, and all the net information can be found at http://www.hwn.org/
Dean looks like it will make landfall around Cozumel and then pass on into the gulf where it should strengthen again before hitting landfall somewhere around Brownsville, TX, according to the more recent forecasts from NOAA and the National Weather Service.
Timing of this storm is interesting for the amateur radio crowd since this is the weekend for the large ARRL National Convention in Huntsville, AL. A large number of radio operators go to the Huntsville hamfest each year but this year a larger number will be making the trip because ARRL’s convention going on at the same time. Many hams I know in the Alabama gulf coast have already left the gulf area to go to Huntsville, but all will be keeping an eye on Dean this weekend from up north. 73, KI4WLR