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HOWTO: Getting Started with CW

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

It's been a year since my post about Morse Code: Brief History, and I figure I might as well shed some light on how to get started operating with Morse Code. Since the Morse code requirement for ham radio was lifted in 2007, the number of amateurs getting their HF privileges has grown substantially, but with the "repeal" of code, entry level Technicians are granted privileges in certain portions of the bands. Most commonly, Technicians can operate SSB in the 10m band, but can also operate CW, or Morse Code, in 80m, 40m, 15m, and 10m. So, if you're a ham, you already have privileges to operate CW - you just need to learn where to start.

Learning the Code
For starters, you will need to learn Morse Code, one way or another. (duh.) While it may not be the universally agreed upon best way, I learned Morse Code through the Code Quick program. It really is an easy way to learn and quickly remember the code. There are countless gimmicks and "5 Minute Ab"-type programs that try to rush you through the learning process as fast as humanly possible, but few are ever successful. You just can't hurry the learning process. The downside of the CodeQuick method is not immediately known until you're trying to copy signals that are faster and faster. Once you hit about 10wpm, the CodeQuick lessons that you've used as a crutch finally become a hindrance and make copying code faster more difficult. The big plus is how quickly you'll learn the code in relatively enjoyable lessons compared to other methods.
Another alternative to learning the code is one of dozens of Koch method trainers. The Koch method, and most others, ram the code into your head seemingly through brute force. You learn the code, but for most people it simply is not entertaining or enjoyable as CodeQuick. However, the hard work you put in up front pays off in the end as you are able to increase you speed with relative ease compared to the CodeQuick program. So it's all about where you want to put in the work, now or later. Because most people because frustrated or quickly lose interest with other methods, I recommend CodeQuick in spite of the "plateau" effect you encounter when trying to speed up your copying skills. Unless you enjoy learning it, the learning curve is almost insurmountable.

There really is no substitute for the "sweat equity" you're going to need to put in to learning the code. It will take time to learn, there's no magic pill. I listened to the CodeQuick training lessons when I was in the car by myself. I wasn't bothering anyone else and I could pass the time by learning something. So consider your personal schedule and think about when you might have time to idly study code.

Copy, copy, copy
Knowing the characters and having the recall ability are helpful, but you still need to try some "live" copy. That is, it's easier to send letters when you know what they are; it's another thing altogether to try to understand what another person is trying to tell you.
There are several practice resources available on the web that will send you random letters or news headlines in Morse code. Copying code is harder than sending code, practice copying others' code more than you practice sending your own.
One of the best sources to copy live code on the air is to use the ARRL station W1AW, which transmits at set speeds and specific times. W1AW transmits a very strong signal, so you should have little trouble hearing the practice sets in North America.

Terminology
As with all things, there's some terminology with Morse code. WPM is a commonly used acronym for "Words Per Minute". That is, the speed at which the numbers and letters are coming at you. For the sake of standard measurement, WPM has been defined as 5-character groupings. If we're talking about 20wpm, that's going to be about 100 characters in a minute.
Farnsworth spacing is the act of sending letters at one speed and pausing in between each letter at a different speed. For example, if we're talking about 20wpm, that's 1.6 characters a second - pretty fast! Now, for beginners, the goal is usually 5wpm. 5wpm has become the baseline for proficiency in Morse Code. at 5wpm, that's one character every 2.4 seconds - much slower. As you learn the code, you'll hear 5wpm characters and find yourself impatient. The individual dits and dahs are so spread out, it's hard to hear them as one whole character. Suddenly you hear just E's and T's. (E = dit, T = dah) The solution to this "slow character" rate is to use Farnsworth spacing. You might receive characters at 15-20wpm, but pause a second or two in between each character so you have time to think and write down the letter you heard. That would be 15wpm letters at 5wpm spacing, or "5wpm Farnsworth spacing". The beauty of Farnsworth spacing is as you become faster and faster, the only thing that needs to change is the spacing between characters. The idea is that you'll go from 5wpm to 15wpm without even noticing (over the span of days/weeks of practice).

Getting on the Air
Ok, ok, ok... You've done your homework, you know the code. You're tired of waiting. How do you actually get on the air?
This was exactly where I was for years. For years I knew the code, but I never used it. I was still sitting at 5wpm, but never had any airtime. That all changed when I stumbled across a segment of the CW portion of the dial. For some reason, nobody ever explained to me that if I wanted to meet other 5wpm hams, I'd have to start in the "Novice portion" of the bands. I had listened to and failed to copy hams down in the lower part of the CW bands. This one evening I stumbled across a radio contact (QSO) somewhere between 7.100 and 7.125. I wasn't able to copy 100% but they were going my speed! Wow, I was able to copy their callsigns and even pick up on the gist of their conversation! Finally, there are other beginners out there like me - I just had to know where to look. If I can offer one bit of advice to other would-be CW operators, it's this: Listen around 7.114MHz on the 40m band. If you only remember one thing of this entire write up, it's to remember this portion of the CW bands. I was a frustrated CW wannabe until I "discovered" the Novice bands. You'll almost always hear someone around there and they shouldn't be going too much faster than you can copy. It's the absolute best place to start with learning code. 10m may not propagate all the time, 15m can be finicky too, 80m is good, but not as popular for slow speed as 40m.

The Exchange
Chances are you've already read how basic QSOs go, they're usually chalk full of acronyms, lingo and abbreviations, but they generally go like this:
CQ CQ CQ de N5DUX N5DUX CQ K
N5DUX de W1AW W1AW W1AW K
W1AW de N5DUX = RST 599 = QTH TX = NAME TOMMY = QSL? K
N5DUX de W1AW = FB TOMMY = RST 579 = QTH CT = NAME HIRAM = BTU K
W1AW de N5DUX = THX FER CALL HIRAM = JUST LRNING CODE = 73 de N5DUX K
N5DUX de W1AW = OK TOMMY = KEEP IT UP = 73 de W1AW SK

Copious amounts of abbreviations are used with Morse Code. Misspelled words while a travesty on the internet are understood for the sake of time in Morse Code. Saving a dit or dah here or there can add up over the course of a conversation. QSL, K, QTH, CQ, RST, 73 - all of these are abbreviations commonly used in CW. (QSL = "do you copy?", QTH = "my location", CQ = "seek you", RST = "signal readability, strength, tone", K = "over/back to you", 73 = "best wishes, goodbye")
So, now that you know the most common abbreviations (known as Q codes), you can probably gather the gist of the exchange. Basically N5DUX is calling out to see if anyone can hear him. It's the radio equivalent of a fisherman putting his hook in the water. W1AW comes back with his callsign, saying it 3 times to ensure N5DUX copies it correctly. Once he does, N5DUX acknowledges W1AW by calling him specifically and tell him how strong his signal sounds to his location. He informs W1AW of his location and then gives his name. W1AW, upon receiving this, replies with his information. Right there is generally what is regarded as a "contact", everything else that may be exchanges are niceties and can be as brief or as long as possible.

Equipment
In order to make your CW experience as comfortable for you as possible, it pays to have a good setup. Of primary importance, is the radio and antenna. You will need a radio that can operate in your intended band. If you're just getting started, you may simply want a radio that can receive CW until you feel more at ease with copying code. Some general receivers have CW mode, but you will need to ensure you can hear the "dits and dahs" before anything else. Most modern HF ham radios support CW (in part because it's such a simple mode to have on a radio - arguably the easiest!).
Once you have a receiver you will need an antenna. The easiest antenna for constructing is the dipole. If you're only receiving, you don't need anything fancy. In general, the more wire the better, but a tuned antenna for 40m is the most efficient and will provide the best signal.
If you are planning on transmitting, I suggest getting a good straight key. I started with some MFJ paddles and enjoyed them, but nothing really beats a straight key for truly getting that organic feel of sending code. I picked up an old US Navy "flameproof" straight key from eBay for a good price. It's rugged, solid feel is far superior to the under $10 straight key you'll find in junk bins at every hamfest. Those will work if you've got nothing else - but then again so do paperclips and thumbtacks.
Beyond the radio equipment itself, I recommend a set of headphones. Headphones help to block out any distracting noises and help your brain really focus on just the sounds you need to hear.
You'll also need a couple of pencils, a pad of paper, to write down the conversation as it unfolds. Just for kicks an internet connected computer is helpful. Having a computer so you can lookup the callsigns you hear on QRZ.com is a big help. By looking up the other guy's name, you can see at a glance where he's from and his name. These will help you out when he's sending his information to you. It helps confirm where he's from and it also gives your brain a little rest as you already know the information. Just be sure to follow along as he sends it to you, he may not be at home or he may go by another name. (Many hams shorten their names when they're in CW because it saves a few dits and dahs. Thomas may be shortened to Tom, Robert may be Bob or Rob, etc. (On a personal note, I go by Tommy in CW because that's my day-to-day name. I don't go by Tom on a daily basis and I wouldn't introduce myself to you in real life, so I keep it Tommy in CW. Besides T-O-M in Morse isn't as "fun" as T-O-M-M-Y. The -.-- on the end is a bit more fun and recognizable. )

First contact
If you're station is all setup and ready to make a contact, you'll probably get a bit nervous. Calling CQ is one thing, copying someone's response is another. I'll admit there were times I called CQ repeatedly and when someone came back to me, I effectively "hung up" on the guy. When I heard my callsign coming back to me I got excited and scared. I completely lost my ability to copy and just turned off the radio! It really happened - silly I know. (Sorry whoever you were!) Radio contacts don't have to be long, but your brain will hurt after just a few minutes of your first few contacts. It's taxing when you are starting out, but I'm at the point now that when the radio contact is flowing, it can be a bit relaxing to hear the letters coming out of the air. That part is hard to describe, but other experienced operators will know what I mean. After all, if it wasn't enjoyable, why would thousands and thousands of hams around the world stick with it? I digress.
So your first call should be relaxing. Perhaps you know a CW operator near you that can help you along during your first QSO. Having regular practice under more "controlled" conditions can be a big help before you step up to the plate for real. (There's even an ARRL First Contact Award you can receive for that first, memorable contact.)
Another key rule of operating is to never send faster than you can copy. It's your way of telling the other operator how fast (or slow) you need him to send. If the other operator is sending slower or saying "QRS", slow it down a bit for him. If the other operator is going too fast for you, slow down your sending speed to a comfortable rate and even send "QRS PSE" ("slow down please"). Any operator worth his salt will slow down for a slow spped op. (and you don't ever want to be "that guy"!)

Gaining speed
You can read all you want, but eventually you will need to just go for it. After you have a few contacts under your belt, you'll notice you can pick up your speed just a bit. Maybe it'll be going from 5wpm to 6wpm, but eventually you'll find yourself operating faster than you realize. You'll hear another new comer call CQ at 5wpm and it will sound mind numbingly slow. That's when you realize how much you've grown.
Another great way to gain speed is to participate in short, CW "contests" known as sprints. If you have a straight key, the Straight Key Century Club offers free membership. Upon joining, you'll be given an SKCC member number. Write this down prominently, you'll be referring back to it from time to time. Sprints are short, sometimes 2 hour contests that hold no value and are just for fun. As an up-and-coming CW operator, what you'll gain is a lot of experience in a short amount of time. By participating, you'll be able to make a lot of contacts very quickly and each exchange is as brief as possible; so it's "just the facts ma'am". You'll hear the so called "fist" that operators have (the style each operator has of sending dits/dahs, spacing, etc.). You'll also be eligible for the myriad of awards SKCC offers its members.

Further Reading For further reading, download the free PDF "The Art & Skill of Radiotelegraphy", it's full of helpful information and while dry at points, really does explain the entire concept or CW and the use of Morse Code.

I hope some of this helps. I'll expound on this as I can... 73!

User Friendly URLs

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

Thanks to mod_rewrite and a little "why didn't I think of this before?", Neodux now has user-friendly URLs. Now instead of "cryptic" URLs with "?" and "&" signs in them, you can now just type in /read/ and the name of the blog entry you're interested in.

To see this feature in action, you can click on this story's title, or the "Full article" link. This should not affect old links and I'd also ask that you please inform me if you see some functionality is all messed up. I think I caught all possible errors, but you can easily overlook some parts of a project like this.

So, bottom line, links to Neodux should be much more friendly and bookmarks should be easier to understand. Enjoy!

update: Yes, old links should still work. Too many blogs and sites around the web link back to articles here and I didn't want to screw them up. So everything should work seemlessly.

HOWTO: ISS Viewing

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

The fact that there's a space station orbiting above the globe right now has become somewhat passe in pop culture. Not many people are truly wowed at the news of it. Within seconds, a few clicks of a mouse will take you to hundreds of pictures and videos of the International Space Station; but did you know you can see the space station yourself? No binoculars or telescopes needed! I figured I would write up a HOWTO for the uninitiated. It isn't hard, it just takes a little know how.

For starters, you need to know a few terms used when talking about satellites (the ISS is a satellite of the planet Earth).

Azimuth
The first term when dealing with satellites is azimuth. Azimuth is a technical term that means the same thing as heading, bearing or direction. Most people are comfortable with the cardinal directions North, South, East and West. The cardinal directions are fine for general directions, but to know exactly where something is we need to be more specific. When dealing with an azimuth, a number of degrees is stated. 0� is North, 90� is East, 180� is South, 270� is West, and on around to North again. Kinda get the picture? It's a full circle divided into 360 degrees. (Also note, there's technically no such thing as 360� when dealing with Azimuth, because 360� would be the same as North, but that's already 0�.)

Altitude
It's not entirely what you think. Sure altitude means height, but we're not talking in feet or meters here. Remember, we're dealing with observational angles here, so knowing how high something is is of little consequence to us. Altitude in astronomy means "angle above the horizon". Altitude is expressed in degrees, just like azimuth. 0� is at the horizon, 90� is straight up. 45�, you guessed it, is right in the middle. Take a second and hold your arm out parallel with the ground. That's 0�. With your other arm, point straight up. That's 90�. Find 30� and then find 60�. Using these angles as references, you'll quickly be able to find a "close-enough" estimation about most any angle of altitude.

See? Not too hard. Now, let's combine the two.
Point of reference
A good starting point for know where the Space Station will approach from is to first find where North is. If you don't already know which way North is, you can use the Big Dipper to find the North Star which is "true north". Once you have North established, turn and face north. Straight ahead is 0�. Behind you is 180�. To your right is 90�, and to your left is 270�. (Incidentally, the angular altitude of the north star is your latitude on a map.) Now that you have azimuth figured out, you can add in altitude angles to see that you can quickly pinpoint any position in the sky day or night using these two values.

Finding our target
To be able to track the ISS, we need to know it's current position which is constantly changing as the station is in orbit. (It's moving at ~17,500mph!) Fortunately for us, there are several free websites that provide second-by-second positioning of the ISS. The main website that I use for celestial tracking (and perhaps the easiest to use) is N2YO.com. Open up the ISS link in another window or tab and let's look at the interface. N2YO tries to estimate your position based on your internet provider's geographic data. (Which something to be aware of, so make sure it's pinpointing your location correctly! As long as it's within 30-40mi, that's close enough for causal viewing.)
The N2YO screen should show you a table of information with varying degrees of yellow. The brighter the yellow, the brighter the ISS will be during a pass (known as magnitude. These yellow boxes are not the only times the ISS flies over. In fact, the ISS passes over about once every 90 minutes. (Yep, around the world in 90 minutes.)
To see all of the passes over your location, you can click on the grey button labeled "Show All Passes". Quite a few right? They are not yellow, because you will not be able to see the ISS during those passes. To hide the ones we can't see, click the grey button "Show visible passes only".

Reading the Information
To understand the table, read the columns left to right. The first column shows us the date of the pass along with the time you will first be able to see the ISS as it's coming into view, as denoted by the green UP arrow. (The satellite is said to be rising at that time) Times are expressed in military time. Numbers less than 1200 are morning, numbers greater than 1200 are afternoon/evening. To convert to the "normal time", if the time is greater than 1200, simply subtract 1200 from the number. The number next to time/date is the beginning azimuth. At the time/date stated previous, at the azimuth stated, the ISS will begin flying over your position at 0�.
The next column is the highest elevation of the pass, stated with a time and azimuth. Then, finally the end of the pass will be at the time and azimuth in the last column. Using this information and your newfound understanding of azimuth and elevation, you should be able to string along the three key points of the pass to determine the general direction of the entire pass (just connect the dots).
Brightness
Oh, yeah, a note on brightness. In astronomy, brightness is referred to as magnitude, as stated previously. The lower the magnitude, the brighter the object. The greater the magnitude, the dimmer the object.
I also suggest trying to spot the ISS on a clear night with little or no cloud cover, as few visual obstructions as possible, and pick a pass where the maximum altitude is greater than 45� and magnitude is -1.0 or lower. You may be able to see it lower altitude or higher magnitude passes, but you may easily miss it on the lower, fainter passes.

So, what am I looking for?
Phew! - you made it. Hopefully, I haven't scared you off. It really isn't as complicated as it may sound and you'll soon discover that casual viewing of the entire pass does not require you to pin point and measure angles. Once you see it, you'll be able to visually track the brightest and highest flying spacecraft ever. So what will it look like? The ISS will look like a quickly moving star. At times it'll be the brightest object in the night sky, flying very quickly. You'll know it's not a plane because its light does not blink. It also may appear to be going much faster than any plane flying so high up.
Those with binoculars might be able to barely make out the outline of the shape of the ISS as it passes directly over your position (>70� passes).

I hope you've found this helpful, I'll gladly update to clarify anything that may be confusing. Clear skies!

Reference: N2YO - ISS link

Texas Historical Markers

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

While arguably probably not my best work, it only took me all of a couple hours, I present a listing of all the Texas Historical Markers. I don't know why I never linked to it before. Maybe I'm not too proud of it, but I wanted to give you access to it. What features do I need to add?

I discovered one evening that Texas has a database of all historical markers in the state freely available online in a comma separated value file (among other formats). What's a geek to do but grab the file and throw it in a MySQL database!
I whipped up a quick drop-down list of all the marker names and used AJAX to show the marker's text. A couple of simple URLs allow you to see, generally, where the marker is located. ~~I have the location information in the database, but it's not Lat/Long which would make for easy map-making. Perhaps that will be my next step.~~ Found a supporting .txt file that has most of the Lat/Long. A simple JOIN from the database fixed that problem. (though, to be honest, some of the coordinates are way off. Unless Texas has markers in Mexico.)

At any rate, take it or leave it, there it is: http://n5dux.com/histmark/

WAS Complete!

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

After working diligently last Fall, then doing absolutely nothing with HF for most of the winter, I finally got back on the air this evening and finished contacting the last of all 50 states. Tonight I was able to contact Wayne, KB1TMA, for #50, Rhode Island.

I can now say I have talked to someone in all 50 states and will soon have a postcard from each of those contacts to prove I've done it.
Contacting all 50 states has been something I've tried to do for years, but never having a permanent setup made the task near impossible. I was close when I was living in Nacogdoches, but my count started back at zero when I moved to Longview.

Joining and checking into the OMISS net really helped me knock out a lot of states early on, and I probably could have done the entire job in under a couple months if I had really, really tried, but I took a leisurely pace and just happened to check into the net tonight with that last hard-to-get state. So thanks for the help OMISS members.
Next up? Probably the Worked All Continents award. (I only need Antarctica and Asia.) Worked all Canada may not be out of the question, but I doubt I ever get so detailed as to try for the Worked All Counties award.

Programming Challenge 2

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

Ok programmers and code monkeys, it's time for Programming Challenge 2. Nothing overly complicated this time. I was just messing around and thought you'd like this quick little brain teaser.
It's a "just for fun" challenge. Choose your favorite language for this one. Here it goes:

Part A: Display/print a vertical sin wave using * characters.
Part B: Display same sin wave horizontally using * characters.

Part A should get you going in the right direction (esp. if you've never played with the sin functions in your language), but Part B is a bit more tricky. No graphics libraries, cheater.

Post source in comments (must be logged in to comment).

Winner to receive 1 small shot of self satisfaction of completing trivial problem through useless challenge on obscure blog.

HOWTO: Working Ham Satellites

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

A local ham recently asked me the best way to talk on ham radio satellites using what he already has on hand. It doesn't take much, although some more specialized equipment does make it much easier, but the point is - you don't need much beyond what you may already own if you have a basic VHF/UHF station. The following is my email to him:

Which birds to target and how to track them
"The best satellites to start with are AO-27, AO-Echo and SaudiSat-1C. (Satellites go by different names depending on where you're getting your info.)

I usually direct people to Heavens-Above to get the latest pass information. The exact time and angle of each pass varies from day to day, so you either need tracking software or a website to tell you when the next pass is over your location. With Heavens Above, you need to enter your longitude and latitude, so it can figure out the information for you.

I've put in the longitude and latitude in for my QTH here in Longview on this link:
http://www.heavens-above.com/main.aspx?Lat=32.5560&Lng=-94.7474&Alt=365&Loc=N5DUX&TZ=CST
(change the location by editing the link or click on the link under Configuration at the top of the page)

When you go to the website, you'll be shown a lot of different links. For our purposes, we're interested in "Radio Amateur Satellites". Click on that link.

Now you'll be presented a table of all the various satellites that Heavens Above is tracking. I usually find the satellites I'm interested in working, then look over at the "maximum elevation" - this is how high in the sky the "bird" will get. Generally the higher the pass, the better chance of hitting the satellite you'll have. If all you're using is a vertical, 45-degree passes will give you a good shot. But anything greater than 30-degrees should be doable. Because you're not on a directional antenna, you don't need to really worry about the azimuth of the pass. Someday, you may find that you'd like to get a yagi and then direction of the pass will matter.

(edit: Heavens-Above is a good reference, but since most people have to jump through a few hoops to enter their Longitude and Latitude, I've been recommending N2YO more and more. Heavens-Above will show a good table of information so you can see everything at a glance, but if you know the satellites you're wanting to work, check out the table at N2YO's Amateur Satellite listing.)

What frequency?
So, now you know when the passes are occurring, now you need to set the frequency. Here are the uplink and downlink frequencies for these 3 satellites. Note the tone. Remember, you talk on the uplink, receive on the downlink.

name	uplink	downlink	PL
AO-Echo	145.880	435.150	-
AO-27	145.850	436.795	-
SaudiSat-1C	145.850	436.795	67.0
Int'l Space Sation	144.490	145.800	-

Doppler
Ok, so there are your frequencies. Those are the "actual" frequencies. Remember, Doppler shift does play a part in satellite communications. You will need to go UP a few kHz as the satellite is coming TOWARD you and DOWN a few kHz as it goes past you. (When it is perpendicular to your position, the frequency will be right on the actual frequency.) If that makes your head hurt, just know to start about 15-20kHz above the actual. As the signal gets more "scratchy" sounding, you'll know it's time to drop ~5kHz.

Listen first!
Listen, listen, listen. Just because you can't hear it, doesn't mean it can't hear you! It's a repeater in many respects, and if you're calling and calling and calling, you're tying it up so others can't use it. If you plan to operate chiefly during daytime hours, you'll hear A LOT of guys crowding onto the satellite each pass. You'll hear quick, rapid-fire exchanges. "N5DUX Echo Mike-22" "Ok, N5DUX, EM22 - this is W1AW, FN31" "Roger W1AW, FN31, 73." - and that's all it is usually. A quick exchange of grid squares, seldom a signal report and rarely much conversation. That is, during the day. At night it's a different story. When all the "sane" people are asleep, you can get on an FM satellite and have a full QSO for the duration of the pass, sometimes up to 15 minutes - always remember though, you have an entire continent of hams that may be wanting on the satellite too, so keep some space between exchanges.

So, tune your radio to the downlink frequency, find the next pass and see if you can hear the satellite.

Recording
A tip I've picked up along the way: The operators are going to be throwing out their info very quickly, so you may need to make a recording of the pass, so you can go back and replay the whole thing to get a second chance of copying their info.

Once you know you can hear the signals, throw out your callsign and see if someone comes back. It's just a really busy repeater, so don't give up. Also, realize that since you're only using a vertical, you won't have as strong of a signal as others will, so you may get stepped on or not heard. Don't give up - try later in the evening when not many are on.

CW telemetry
If you have a dual-band antenna, that would be even better for working sats from a vertical. A mono-band 70cm will work fine for receiving, but for transmitting the uplink you'll need a resonant antenna on 2m.

That's not to say you can't have fun with the 70cm alone. If you have a multimode 70cm radio, you can also copy telemetry data from other satellites that is sent down in CW. It's not the most exciting stuff right away, but copy one satellite over a period of a few days and you can monitor how it's on board temperature swings as it passes in/out of the sun/earth's shadow and stuff like that. It's just fun to copy CW from a little satellite 200+ miles away. The one I copy most often (when I do try to copy) is RS-30 Yubileiny. Unfortunately it isn't tracked on Heaven-Above, so I have to use this other website that's pretty handy, N2YO.com
Yubileiny's track: http://www.n2yo.com/?s=32953

After you decode the info, check out how to "decode" the info by Googling for "RS-30 telemetry", or use a tool like those found here for free: http://www.dk3wn.info/software.shtml Check out the telemetry hypothesis section here to decode the seemingly random strings of info: http://www.ne.jp/asahi/hamradio/je9pel/yubilein.htm

So there you have it, a beginner's guide to getting on the birds with stuff you probably already have. For further reading, check out this page from AMSAT and, of course, scour Google for all it's worth!

update: It should be noted that as of sometime in Spring 2011, AO-Echo began experiencing difficulties with its onboard batteries. The command team cannot keep the control system loaded effectively taking AO-Echo offline. AO Echo is as good as dead until further notice.

update #2: AO-Echo is back online now. Thanks for the heads up Schrockwell. Echo is online running at 2/3 her input power and running 1W output. Note the changed frequencies. These are not the same frequencies Echo has been using since launch. There are the "QRP" frequencies.

Morse Code: A Brief History

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

Most people know the important life-saving phrase Di-di-dit da-da-dah di-di-dit (SOS), but that's about it when it comes to Morse Code. Many people know that Morse Code was named after its inventor, Samuel Morse but not much more. Fewer people know that the use of Morse Code still persists (unless, of course, you know someone that uses it on a semi-regular basis!).

Morse Code is the oldest form of telecommunication still in use. It got its start when the legendary Samuel F. B. Morse, an artist by trade, began to experiment with methods to communicate via the relatively new field of electricity. Morse's system of communication was not the first form of telegraphy, nor was his invention the only electric telegraph. But he did invent a language of dits and dahs that, by way of a few revisions, remains in use to this day. (The history of the telegraph, interesting in its own right, is beyond the scope of this outline.)

Ham radio operators are perhaps the most notorious users of this antiquated form of communication, but not the only users. Navy signalmen use Morse Code when manning the Signal Lamp and aviators make use of the Code as a way of identifying directional beacons.

Morse Code has undergone few revisions since its inception. Morse's original code was a bit cumbersome, but the idea was there and several letters have remained unchanged. Morse originally planned the letters to leave imprints on a printed tape, but over time the code was learned by operators and the incoming signal was able to be decoded by ear rather than on paper. In order to speed up transmission, Morse gave the most frequently used letters the shortest signals. (E gets a single �dit� and T gets a single �dah�) Identifying the most frequently used letters, Morse counted letters in a copy of the newspaper. The letters with the highest count were most used. Perhaps not the most technical method of finding the letters, but it was an easy and straight forward approach and has proven its validity. These most-used letters are some of the letters that have never changed.

As Morse�s Code and the use of the telegraph grew, operators using the code found ways to improve the characters� codes. Due to some spacing issues, some letters were slowing down transmission speeds and/or confusing the receiver. (Some letters required a �space� or pause in the middle of the letter rather than sending a continuous series of dits or dahs. A resulting �space� between letters could then be misconstrued as a different letter altogether and throw off the transcription of the message.)

Morse made his code public in 1844. After a few years of use, Freidrich Gerke released his �improved� code alphabet in 1848 which came to be known as the Continental code. Gerke essentially removed the aforementioned spacing errors eliminating much of the confusion for telegraph operators. Finally in 1865, the International Telegraphy Congress standardized the code to form what is now known as the International Morse Code.

Once the International Code was in place, it has not changed in the nearly 150 years since. Telecommunications has changed completely transformed the way mankind communicates. The advent of radio ushered in easy-to-establish distance communications that required no connecting lines like that of the telegraph, yet the code did not change. Even in the advent of digital communications, the code remained a fixture in the telecommunication industry. It was not until the later 1990�s that the international community began reevaluating the use of the code. Mariners, aviators and radio operators worldwide needed to be proficient in Morse Code to perform their duties, but all this changed in the past 10 years. In spite of its fall from common usage, code operators of today would have no trouble communicating with telegraph operators of the railroad era via the code. No other form of communication can boast a 150 year heritage.

In radio communications, Morse Code continues to be a form of signaling that prevails when almost no other form of communication can get out. No other form of communication can go further on the same amount of radiated power. No other form of radio communication is easier to construct circuitry for. It is simple and efficient.

For those curious individuals wanting to hear Morse Code in use, YouTube offers a wide variety of operators making contacts, there�s the famed Tonight Show video showing the text message versus Morse Code race, and there�s always the ham radio bands.
I was unable to ever make real contacts in Morse Code until I discovered the 7.100-7.125 portion of the 40m ham band. For those looking to break into the world of CW operation, tune your dials to the Novice portion of the band and you�ll find other code operators that welcome �slow-code� newcomers.

mod_rewrite: URL modification

Corey — Thu, 01 Jan 1970 00:00:00 -0600

To say that there is extensive documentation on Apache and its various plugins, including mod_rewrite, is to grossly understate the term. Documentation is voluminous to the point of beginning to wonder if the various authors had a combined total of more than five dates with actual girls in the history of their lives.

Disgruntled, then, was I to discover that on the entirety of the Internet, there was no documentation surrounding what I needed to accomplish. I've since come to realize that this is likely due to the obscurity of the issue or the availability of other commonly known tools to accomplish the task I had before me.

That task: Rewriting and redirecting a URL from my local environment using Apache and mod_rewrite.

Without delving into specifics, I needed to take an HTTP request generated by a page viewed in my browser and direct that request to another location, including a change of domain.

Now, the more seasoned among you may resolve that the very purpose of mod_alias is to perform this task. However, just because I'm a glutton for punishment, in this particular case, I also need to change the value of a query string parameter in the URL having its domain changed. Gaze upon the domain of mod_rewrite, ye mighty, and despair.

While mod_alias is designed to handle the translation of domains, mod_rewrite is designed to handle that and query string parameters (as well as a bunch of other stuff that I have no idea about). Before we can start directing URLs to and fro, we must first setup Apache.

I'll not regale the reader with the riveting tale of that process as it is rather well (and usefully) documented. The mod_rewrite module must be included in httpd.conf and the Apache instance must be configured to run as 127.0.0.1 on port 80. Do be wary of configuring the server value as localhost because sometimes the value does not translate, especially in Windows. My Apache setup is in Windows 7 x64 with OpenSSL.

The next thing to do is to direct all HTTP requests from the domain that needs to be changed to the local instance of Apache. In Windows, this is easily accomplished via the Windows HOSTS file. An example entry would look like this:

127.0.0.1 ihatecake.neodux.com

This entry will override DNS requests for ihatecake.neodux.com and point it instead to localhost. Apache takes over from there.

With that in mind, let us consider an example URL value:

http://ihatecake.neodux.com/serve?feedme=pie

Clearly, no one hates cake and that pesky query string is returning pie instead of cake, which simply isn't fair. This injustice will not stand; we must modify and redirect this request to attain cake righteousness.

In order to engage mod_rewrite, the traditional method is to add rules to Apache's docroot in the .htaccess file. Because we're not actually dealing with anything in Apache's docroot (despite all the documentation examples using only this scenario), these rules need to go inside httpd.conf. Assuming you've got Apache configured and running, this is quite simple. At the bottom of your configuration file, add a virtual host for your localhost instance of Apache and include the rules to enable mod_rewrite's magic. The first step is to turn the mod_rewrite engine on. It looks like this:

NameVirtualHost 127.0.0.1:80

RewriteEngine on

The next step is to write a conditional statement inside the virtual host instruction set looking for the feedme query string parameter. In Apache, mod_rewrite accomplishes this via regular expression. Now before your panties fully bunch, allow me to assure you that this implementation of regular expressions is very simple once you break it down, so don't let the syntax scare you. The conventions are largely the same as those used in perl, so if you're a perl nerd this will not seem out of place. These condition and rule execution statements accomplish our goal of translating ihatecake to ilikecake and the feedme query string from pie to cake:

NameVirtualHost 127.0.0.1:80

RewriteEngine on

RewriteCond %{QUERY_STRING} ^(.*)feedme=pie(.*)$
RewriteRule ^/.*serve.*$ http://ilikepie.neodux.com/server?%1feedme=cake%2 [R,L]

Let's break it down: The first thing I did is to write a RewriteCond statement that evaluates the query string of the URI for feedme=pie. Most mod_rewrite rules follow the basic convention of RuleName Pattern Pattern, so the RewriteCond rule matches the %{QUERY_STRING} Apache variable against the second pattern. The carat tells mod_rewrite that this is the beginning of a string. The (.*) essentially says, "This means everything before feedme, and since I'm wrapped in parentheses, remember my crap for later." You'll see another usage of that after feedme=pie, so that the entire statement reads [everything before feedme=pie]feedme=pie[everything after feedme=pie]. The dollar sign then signifies the end of the string. In this way, mod_rewrite is able to localize on what you actually want to modify. The purpose, and dare I say the beauty, of the RewriteCond statement is that the RewriteRule statement will not execute unless RewriteCond finds what it is looking for.

The second statement is the RewriteRule. where the URL is modified. Based on what we found (and stored) in RewriteCond, RewriteRule starts its search for the end of the URL, /serve. Again, we see the use of the carat to signify the beginning of a matching string, and the use of .* to mean, "Everything before serve." The dollar sign marks the end of the first pattern string. The second pattern string contains the values we want to change the incoming request to. Since I want to go to ilikepie instead of ihatepie, I can substitute the literal translation here, which I find to be incredibly helpful. After server, where the question mark begins the query string, the usage of the %1 variable says, "Put anything that existed before feedme here." Remember, the condition statement only matches against values found in the query string, so this allows you to rewrite requests that have multiple query strings and/or where feedme is not necessarily the first query string in line. We then substitute the feedme parameter value of pie for cake, and use the %2 variable to include anything that came after feedme.

That's it, right? Close, but there is the matter of the bracketed values out to the right, [R,L]. These are mod_rewrite flags that tell Apache to do certain things. All the flags are covered in the regular mod_rewrite documentation, but R and L are fairly common in their usage. R tells Apache that this should be a redirect, not referencing something in Apache's docroot. If you have a specific need to have the redirect be 301 instead of 302, you can specify that as R 301 or R 302, but it defaults to 302.

The L flag, literally translated, means last rule. It is designed to make mod_rewrite stop looking for additional rules if this rule is successful. This is helpful if you have several RewriteRule statements and don't want to risk having a modified request modified again incorrectly. Also remember that mod_rewrite rules are processed before mod_alias rules and other modules, no matter where they are in relation to each other inside httpd.conf. In essence, the rules are not processed serially.

To test this setup, you can write a local page and view it in your browser. Ensure that you view it via Apache and not from the file via the OS. Using an HTTP request logger like HttpFox for Firefox, you can see the redirect and translation occur in real time.

HTTP request rewriting and redirecting is usually something found in the realm of Squid or other proxy servers. While those tools do work well, novice users (like me) tend to have profound difficulty in getting through the initial setup because those tools are so powerful and have so many options. The setup and operation of Apache, especially as a local web server, is far easier and there are a lot of easy to understand tutorials and other documentation available for it. It's also easier in Apache to lock down access to your instance to only localhost or only your LAN subnet that it is in some other tools.

While this may be elementary to a seasoned Apache guru, I am, by far, not a seasoned Apache guru and it took a great deal of time (and some help from an Apache guru) to make this work for me and to build my understanding of it. Because this specific application of Apache and mod_rewrite was not documented anywhere I could find on the Internet, I though it should be included in the annals of Neodux. Hopefully the next poor fool who needs to do something like this can find it via Google search instead of banging his head against the wall for a week like I did.

Continue Reading...

Tommy — Thu, 01 Jan 1970 00:00:00 -0600

After the success of the DUX Yagi-Uda post and it finding its way to Hack-A-Day, I decided I should probably go in to more detail with each blog entry when I'm attempting to explain something technical.

In the past, I've tried be as succinct and just-the-fact-ma'am as I can so the article doesn't make the main page a mile long. I always assumed if you wanted to know more you could just ask me. But, more often than not, I ended up with an article that I think was too shallow or too "in-passing". So, for the sake of those that don't know me personally and would like more information, and in keeping with the spirit of information exchange on the web, I think it's best if I link to and explain all relevant information. To keep the main page short I've decided to limit the amount of words in a story that gets shown at a glance.
I've broken up the links to have the "Continue reading..." link on each article if it is longer than a preset length.

I'd really like to know what my core users think of this change. Is it for the better? Should I change the wording of the link? Should I display all information, longer or shorter at-a-glance summaries? You tell me.