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Amateur Radio Starter Kit
radio : by Tommy - September 26th 2016, 07:16PM
I recently posted on Facebook for some friends about an incredibly cheap radio out of China. It's the Baofeng UV-5R.
The little dual-band radio has been the source of much consternation among the old guard of amateur radio because of it's cheap construction, low quality display, and some technical problems with the radio (some which make it technically illegal to operate on some frequencies). However, it is 100% legal to operate on the 2m amateur band (144-148MHz). The price of this radio is what makes all shortcomings able to be overlooked. It costs $25 on Amazon with free shipping for Prime customers!

Now, the radio is not a super great radio, but it's a phenomenal starter radio. (Or, as I call the one I keep in my car, a "burner" radio. I can drop it, lose it, or have it stolen and I simply would not care.) If one were to purchase this little capable radio for the mere $25 price tag, one should also get a couple of pieces of kit that should be standard: a better after-market antenna (Option 1 or Option 2) and a USB programming cable in order to program all the frequencies of nearby repeaters using software like CHiRP. All in, the whole kit still comes in around $40 which is still a fraction of the cost of a dual band radio from one of the major amateur radio manufacturers like Icom, Kenwood, or Yaesu.

Study, study
Anyone interested in amateur radio should consider studying for their license before dropping any money on a radio. While the radio is cheap, it's still money wasted if you can't use it because you don't have a license. The student guide's I most often recommend are the Technician study guide by Gordon West, WB6NOA, or the Technician study guide by the ARRL.

Continue reading...

tags: ham_radio license radio

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CW Works
radio : by Tommy - February 16th 2016, 04:32PM
I posted earlier about my new MountainTopper Radio. They're only being made and sold in small batches so I was never able to get my hands on one until January 2016. When I visited the site and saw they were for sale, I jumped at the opportunity to secure one of the little radios and it arrived a couple of weeks later. I had a business trip to go on so I wasn't able to fully get to know the radio until I got home. After I got home, the following Monday I got on the radio with the manual open on my computer. I got a feel for all the features packed into the limited number of buttons. After a while I really got the hang of it.
The next night (Tuesday) was a NAQCC Weeknight Sprint (a mini 2-hr radio contest) and it was also a night when class was cancelled. The 40m band was in pretty decent condition that night and I easily nabbed 5 different states. At the conclusion of the contest I made a couple more contacts and decided I loved the little radio. I've been using it nightly for the past week, making at least one QRP CW contact each day ...and that's where I've learned something.

It's something I heard guys say over and over again and, like you reading this, I've seen others write about: CW Works.

It's not just some old geezer claiming his tastes/choice mode is superior. What I mean to say is when the bands are great or incredibly noisy, CW still gets through. To modify the slogan "When all else fails... CW". Sure, digital modes get through when conditions are equally rough. (I first learned that late at night during Field Day one year using PSK31.

Continue reading...

tags: ham radio cw

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MountainTopper Radio
radio : by Tommy - February 16th 2016, 10:25AM
It's been quite a while since I last made a post but this is one I have to mark the occassion for. For the better part of the past 6 months I've had my eye on the MountainTopper Radio. It's a small QRP CW radio designed by Steve Weber, KD1JV, and sold by LNR Precision. The model I got is the 3-band version. (At the time of this writing there are rumors stirring about an upcoming 5-band version. Since I'm really only active on 40m and 20m, I'll pass on the 5 band model.)

The radio is very small - about the size of a deck of cards. There's no internal antenna tuner or battery. The volume, RF gain, and filter settings are fixed so there's no need for adjustment knobs. Nor is there a tuning knob. Tuning is done by two push buttons (UP and DOWN) that nudge the VFO up or down 50Hz. Holding down the button will change the frequency in 100Hz steps at a rate of 10 steps per second.
The elimination of knobs on the face of the radio allows the radio to pack very small. It's so small in fact, I was moved to get a Micro key from KK5PY. It has to be the smallest paddles I've ever used. To match the small size, the MTR can be powered by a 9V battery or a small 12V LiPo battery pack. Pack in some earbuds, a wire antenna, and a paper logbook and the whole kit fits into a small padded, zippered case ready to go. It's a radio meant for travel! I can't wait to take it on the road with me.
I've been using it to make QRP CW contacts each day for the past week and I'm going to try to get QRP Worked All States on 40m CW.

Continue reading...

tags: ham radio qrp cw

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WebSDR on Raspberry Pi
radio : by Tommy - August 10th 2015, 05:12PM
In Fall 2014, I setup my first Raspberry Pi WebSDR receiver for the 40m amateur radio band. In late July 2015, the Raspberry Pi stopped working at all. Once I hooked a monitor up to it, I learned the SD card had been corrupted. I'm now in the process of rebuilding the receiver and will be updating the steps required to setup this project on my project page.
The receiver hardware itself is fine and operational, it is only the WebSDR host (Raspberry Pi) that is out of commission.

For now the WebSDR and ISS iGate must connect to my home network via a wireless link from my ham shack behind my house. I'm in the process of digging a trench to run a network connection out to the shack so I don't have to wrestle with spotty wifi coverage. I'm going to be running fiber optic for the main run for reason I'll explain that in an upcoming post.

tags: raspberrypi ham radio raspi linux

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Raspberry Pi TNC ISS iGate
radio : by Tommy - April 8th 2014, 02:04PM
Not so long ago I completed construction of my Raspberry Pi TNC, the TNCPi. Construction of this kit was very straight forward. A few additional pictures would have made this a great kit for beginners, but still the same it's an easy build.

Building Tips
A couple of items to note regarding construction. Ensure the correct polarity of the electrolytic capacitor (C1): The negative stripe goes toward C15.
The transistor (Q1) PN2222's flat side goes away from the edge of the board.
The voltage regulator (U1) MCP1700's flat edge goes toward the edge of the board.
Crystal X2 (20MHz) is near U1. Crystal X1 (3.57MHz) is neat Q1.
Note the pin 1 position of all ICs.

Interface cable
After completing assembly of the TNC, I set to work on creating a radio interface cable to connect to the DB9 port on the TNCpi.

The pinout for the TNC Pi matches the TinyTrak cabling:
Pin 1TX Audio
Pin 3PTT
Pin 5RX Audio
Pin 6Ground

Tuning Audio Output
After creating the cable, I set the audio output level as noted in the instructions. To do this, you'll need two radios. I used 2 HTs, one that I had created the interface cable for and a spare. Tune the radios to the same frequency (I used 144.44). On the radio with the interface cable, I pressed the PTT button and heard a tone being transmitted to the neighboring radio. Adjust R7 to it's maximum volume before it begins to distort.

After tuning the audio, the TNC Pi project is complete. How you plan to implement the TNC Pi is entirely up to the software you choose. For many, this may be Xastir for an APRS GUI. For others, it may be aprx to create an APRS beacon, iGate, digipeater or any combination of the three.

tags: raspi aprs ariss iss tnc raspberrypi

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HOWTO: Configure Hamlib for Linux Hams - Part 2
radio : by Tommy - December 3rd 2013, 06:48PM
This is a continuation of a two part series about how to configure hamlib for Linux ham radio users.
To get started, be sure to read through Part 1.

In the last post, I pointed out that hamlib was create to simplify the once fragmented world of computer control for amateur radio. With hamlib in place, developers can interact with hamlib which serves as an abstraction layer of sorts for software development. Developers don't need to worry that you're running a particular model of radio, so long as you get your radio working with hamlib, your radio is supported.
I'm going to assume you have /dev/radio and /dev/rotator already configured (since we did that in the previous post). Now, we're going to configure the daemons (servers) that allow a myriad of radio related applications to interact with your amateur radio equipment.

Hamlib centers around two core daemons: rigctld and rotctld. The daemons receive commands from applications via TCP. It is possible to have these daemons controlled via the network if you so wish. That functionality is a bit beyond the scope of this article, but the concepts below are exactly the same and just requires the correct ports be opened. Speaking of ports, rigctld and rotctld use ports 4532 and 4533, respectively. Also note that there is no security built into these devices. Should you need external connectivity, you should create an SSH tunnel.

Find your equipment
The first step in configuring rigctld is to find if your particular radio (and rotator for rotctld) is supported. Here is a list of all supported radios for rigctld (chances are, if it's a modern radio with computer interface, it's supported). For rotctld, things get a little more difficult. In order to see if your rotator controller is supported, you need to identify which protocol is supported.

Continue reading...

tags: ham radio hamlib linux satellite

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HOWTO: Configure Hamlib for Linux Hams - Part 1
radio : by Tommy - December 2nd 2013, 8:11PM
Linux and ham radio, where two of the geek worlds collide. Fortunately, with so many geeks involved in both pursuits, a lot of great tools have emerged. Unfortunately, documentation on how to configure some of it was hard to come by. (At least, it seemed that way to me.) Here, I hope to layout as quickly and easily as possible the steps required for other hams to configure hamlib on their linux computers. I'm going to assume you're running a modern version of linux and have a USB connection to your radio and/or rotator.

What is Hamlib?
First of all, Hamlib is a set of ham radio control libraries that allows amateur radio operators to control their radio and antenna rotators via their computer. Hamlib abstracts many device-specific control issues from application developers, allowing for a more robust user experience across several programs. Prior to hamlib, there were several different tools and libraries. None of these tools provided a common API for programmers to interface. As a result, the application landscape was fragmented and functionality suffered. Now, with hamlib, programmers can utilize hamlib to interact with a whole range of devices.

To use hamlib, you must first have a computer interface cable from your radio to your computer. Without this, everything else here is pretty useless. If you don't have a cable yet, look on eBay for cables tailored to your radio. (It's where I found mine.)
My radio is a Yaesu FT-847 which has a DB9 serial port for CAT computer control. To interface with my computer, I use a cheap USB-to-serial adapter - nothing special. My antenna rotator is a Yaesu FT-5500 with the brilliantly simple WA8SME Satellite Tracker Interface from the ARRL.

USB, Linux and udev
Most modern distributions of Linux include a subsystem to handle when USB devices are inserted.

Continue reading...

tags: ham radio hamlib linux satellite

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HOWTO: NOAA Weather Satellites
radio : by Tommy - August 7th 2013, 11:31AM
Most people are aware that every day weather satellites pass overhead to get a glimpse of the nation's weather patterns. Many people, especially those outside the ham radio community, are unaware that the signals these NOAA weather satellites transmit are readily accessible with a minimum amount of equipment. These satellites use a technology known as APT, or Automatic Picture Transmission. NOAA-19 is perhaps the easiest APT satellite to receive because it provides the best, strongest signal for visual satellite imagery. Because of this, we'll focus on NOAA-19 for this post.

All you really need to receive the satellite's signal is a radio receiver like an old police scanner (found at thrift stores) or a simple 2m ham radio handitalkie (like the Baofeng UV5R). An external antenna is usually better, but not a requirement for casual reception of the image. Other than the radio, the only other pieces are a computer with sound input and an audio cable (to get the audio out from the radio to the input on the computer).
If you would like to get the best images possible from every pass of the satellite, use an outdoor antenna connected to your radio. Discone antennas for scanners work well, as will any 2m amateur radio antenna. These antennas do suffer from "fades" where the gain of the antenna is weakest. To minimize these anomalies, eggbeater antennas or the very common quadrifilar helical antenna are used by serious hobbyists and weather professionals.

Once you have the required hardware, download the free WxToImg software which is available for Windows, Mac and Linux. There are other features and enhancements to the software if you upgrade, but it's still not a requirement.
Once the program installs, the first time you start the program you will be prompted to enter your Latitude and Longitude.

Continue reading...

tags: radio noaa-19 wx satellite howto

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Ham Radio PDF Archive
radio : by Tommy - March 26th 2013, 04:11PM
The other day I went looking for an old issue of the once-free publication WorldRadio Online, but had trouble finding all the issues in a single repository. I decided to make myself one once I found all the files. So here it is: www.n5dux.com/ham/pubs

WorldRadio used to be a very low key, cheap publication about amateur radio. The kits and homebrew articles were worth a look. WorldRadio had a small following but when the much larger CQ magazine offered to buy-out WorldRadio, the owners of WorldRadio gave in. CQ has far more advertising dollars to support their publications (CQ, CQ-VHF and PopComm) - for them, it's a business wrapped around a hobby. WorldRadio was more of a hobby wrapped around a hobby.

So CQ Magazine bought the small WorldRadio, moved their "lifetime subscription" members to a one or two year CQ magazine subscription (crummy deal) and made WorldRadio into a free, online-only publication titled WorldRadio Online. (A move that jilted many of the older, not-quite-so-tech-savvy readership.) Many of the longtime readers said it was the end of WorldRadio, some said it was the start of online publications for ham radio. Both were right. WorldRadio Online was a great monthly treat because it was free. The transition to online was made easier in that the reader wasn't having to pay for it. The content got watered down somewhat as CQ wasn't making much money on the project, but you get what you pay for: no complaints. Still, longtime readers still said the end was near for WorldRadio. In October 2011, they were proven more correct. WorldRadio Online became a paid-for, online-only publication. The once-free PDFs were taken down and any new content would have to be paid for. I'm unaware of any widespread fanbase of the now online-only paid publication which can only mean it's a matter of time before the publisher pulls the plug on the project altogether.

Also succumbing to similar commercial/financial pressures is the European publication HamMag.

Continue reading...

tags: WRO WorldRadio HamMag Ham Radio

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HOWTO: Getting Started with CW
radio : by Tommy - October 18th 2011, 05:50PM
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.

Continue reading...

tags: ham radio cw morse code howto

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WAS Complete!
radio : by Tommy - April 22nd 2011, 10:01PM
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.

tags: was ham radio arrl

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HOWTO: Working FM Ham Satellites
radio : by Tommy - January 22nd 2011, 03:37PM
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:
(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.

Continue reading...

tags: satellite ham radio intro howto

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Morse Code: A Brief History
radio : by Tommy - October 18th 2010, 10:12PM
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.

Continue reading...

tags: morse code ham radio cw

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DUX Homebrew Arrow Yagi
radio : by Tommy - August 7th 2010, 11:36PM
This summer I attended the TI-2 Space workshop put on by the ARRL and DARA in Dayton, OH. We spent 4 days learning how to make contacts with orbiting satellites like AO-27, AO-51 and the International Space Station, just to name a few. The antenna we used was the dual-band Arrow II Antenna. I've owned one for years and really like it. I wish more people had them, but I think most people think spending $140 for an antenna that can only handle 10W is a bit much.

My aim was to make a cheap alternative to the Arrow that is easy to break down for transport and storage. I really like the idea of using aluminum arrow shafts for elements; they are lightweight, straight, weather resistant, and fairly inexpensive. Another nice feature is the #8-32 threaded insert for broad heads that almost every arrow comes with.

I spent a couple of hours reviewing all the "cheap" and "ugly" yagi designs, as well as others like the "tape measure" and even a new-to-me "backpacker" design. They each have their own advantages and loyal followers.

I finally based my antenna design on one found in the ARRL Handbook from 1999. While not an exact replica, my design is very similar. I had decided to go with the through-boom design like the Arrow, as opposed to side-mounted because it is, in my opinion, cheaper. After buying 6 arrows and a quick trip to Lowe's I had a length of #8-32 all-thread and a piece of 3/4" conduit to use as the boom. I marked a straight line down the center of the boom to give me a point of reference, measured out the spacing holes, made sure I was drilling square and level and got to work.

Continue reading...

tags: yagi radio antenna ham_radio

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Elecraft KXAT1 Antenna Tuner
radio : by Tommy - April 19th 2009, 06:50PM
I recently added the KXAT1 antenna tuner kit to my Elecraft KX1. The antenna tuner allows me to automatically tune up any non-resonant antenna quickly. Construction took one evening. As usual, winding the toroids was perhaps the most tedious part, but "zen-like" while I was doing them (as I heard it put by someone). I did have trouble with the transformer. It can be tricky and I'll warn other kit builders to check out this thread if they have trouble. I also found some pictures from a japanese ham helpful, but I've since lost them. :(

After building and installing the tuner, I purchased 40ft of some "silky" 26AWG wire from TheWireMan as suggested by Elecraft. I cut the wire to give me two lengths. One length is 24ft and the other 16ft. The 24ft length is my radiating element and the 16ft acts as my ground. The tuner quickly finds a nice 1.1-1.0 match and gives me full KX1 power out (~4W). It makes for a very lightweight, field-portable antenna. I can also use my crappie poles to elevate one end if trees are unavailable.

I use a BNC-to-binding post that I purchased at EPO in Houston. While at EPO, I also picked up a small 12V 1.3Ah gel cell battery. The UB-1213 is about 3.8" x 1.7" x 2" and provides adequate power for portable QRP work. If I was going to operate for very long, I may go with a little larger capacity gel cell, but for now this makes a very lightweight and super portable setup that allows me to get one the air quickly.

tags: ham_radio qrp kx1 kit

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Elecraft KX1
radio : by Tommy - April 5th 2009, 06:27PM
About two weeks ago I completed construction of my Elecraft KX1 ham radio kit (serial #2182). It wasn't the easiest build I've done, but definitely the most fun. The purchase was funded almost totally by referral bonuses from Dreamhost. When anyone signs up for an account with my referral link I get a kick-back. I had let the bonuses build up over time and eventually had enough to cover the radio, but I digress.

The KX1 is a "trail-friendly", portable CW ham transceiver. There's plenty of other sites that will give you more detailed information about this gem of a radio. I finally got to use mine yesterday for more than a couple of minutes and I must say I totally love it. The receiver is great, the noise floor is low, the filters are tight, and the features are really packed into this tiny radio.

My antenna was a random wire made from speaker wire with one end elevated to 20' using a BnM Black Widow 20' Crappie Pole purchased at Bass Pro Shop in Shreveport, LA. The antenna sloped down to my BLTPlus antenna tuner which tuned the random wire without any problem. I had the tuner hooked into the KX1 with a short piece of BNC cable.

In short order I was copying stations on 7.030Mhz (40m QRP) and trying to copy the faster stations lower down on the band. I had to tighten up the filters because of the sheer number of signals I was able to pull in. I wasn't able to raise any station due to my diminished transmit power. (I was running off of internal AA batteries because my gel cell hadn't been charged in quite some time.) I was also impatient due to the strong wind, fading daylight and biting insects.

Continue reading...

tags: qrp ham_radio kx1 kit

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Rockmite 20m
radio : by Tommy - December 22nd 2008, 12:57AM
After almost a year of procrastination I got around to finishing a Rockmite 20 radio kit. The Rockmite is a single-frequency crystal-controlled ("rock-bound") low-power CW HF radio. Say that 10 times fast!

I bought the kit sometime last year and just never finished building it. I had all of the components soldered in, but I never mounted the board in any enclosure. W5USJ, Chuck, Don, K5DW, gave me a metal enclosure during a North East Texas QRP Club meeting. It wasn't until last Friday that did anything with it. I knew the Rockmite needed a home, and here was a nice case for it. I drilled some holes in the cabinet, more or less eyeballing it. They're not perfectly aligned, but pretty close. So now the little radio is mounted, all of the connectors are soldered in and the radio is functional.

It only puts out about ˝W at 14.060MHz, on the 20m amateur radio band, but because I mostly operate during the afternoons, 20m is my favorite band for now. I may need to boost myself up to a "full gallon" QRP and get a 5W amplifier like the one Chuck designed, which I might get from QRPme.

Also on my "to do" list, is to add a PicoKeyer chip to the radio which greatly adds to the experience of using it.

update: I got the PicoKeyer chip installed this afternoon. I love the features it provides. The Memory Keyer is vital for QRP work and the hands-free "Tune" feature is great for field-portable antennas. Most of the other features I don't use, but I still think the chip should be incorporated into the original design.

tags: qrp ham_radio kit

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Spirit of Knoxville IV Balloon
radio : by Tommy - March 11th 2008, 11:55AM
The University of Tennessee Amateur Radio Club (UTARC) has launched their latest balloon "The Spirit of Knoxville IV". It took flight late last night on its voyage across the Atlantic Ocean, into Europe, via the swift moving winds of the jet stream.

The team put a computer and GPS on board to transmit the balloon's location and altitude via ham radio. The data stream is sent out via RTTY and CW at ~10.146 MHz. The data is displayed in rather raw format here and in a more presentable flash-based "dashboard" which features a Google Maps fix on the balloon's last reported location.

Quite a few people are monitoring the balloon so the site is a bit slow to load, but to track the little autonomous balloon is pretty neat. Right now, as I write this, it's zipping along at 111mph @ almost 40,000ft out over the Atlantic.

update: The balloon fell short of its European goal. The payload splashed down about 2:00pm CST, 425 miles southwest of County Cork, Ireland. The balloon began losing altitude the night before and never full recoverd. The decent was partly caused by the loss of sunlight heating the gas in the balloon and/or icing on the surface of the balloon. "Grams will make/break you in this business," one UTARC member said. The balloon's exact location was unkown as radio contact was lost at about 1:51pm CST. Better luck next time guys!

tags: balloon ham_radio

( Comments : 1 | Full article )

Finally! A Cell Signal!
radio : by Paul - November 10th 2007, 12:43AM
When I bought my new house in April, one of the most annoying things I discovered was that I got virtually zero cell service inside the house. The house is down in a valley and thus has no good line-of-sight to any cell towers. Inside the house I'd get 0-1 bar, and outside on the front lawn I'd occasionally get 2.

To try and remedy this situation, I had two choices: get a landline (with yet another phone number and at least $20/mo) or I could go with a "smarter" solution and get a cell repeater/booster. I found this gem after doing some research online: the YX510 dual-band cell repeater.

So for just over $300 I got this fairly large box containing an 18" external antenna, 35' of high-grade coax cable, and a chunky little box for inside with a little 6" antenna.

I went up on the roof of the house and found that I got 4 bars near the back of the house. So I mounted the external antenna at the top of an 8' 2x4 that I strapped to the side of the house. Then I ran the provided coax around the house into the attic, where I mounted the interior box.

I should note that I took care to put as many physical barriers as possible between the interior and exterior antennas, to prevent feedback loops. In my case, I was able to get 2 sets of shingles and 3 walls in between the antennas.

Finally, I found a good place to plug in the provided wall-wart, then spliced in an extension into the power cable (the provided one was only 4' long). Then I plugged the base unit in, and voila! I now get 4-5 bars all over the house. No more dropped calls, no more "are you there?" when talking to somebody.

Continue reading...

( Comments : 2 | Full article )

Worked All States - Satellite
radio : by Tommy - May 2nd 2007, 03:37PM
Since I got my Arrow Antenna, I've been trying to contact all 50 states by satellite (aka Worked All States). I know a few states are going to be tough (if they're even possible). I know Alaska and Hawaii will probably have to be a scheduled contact. Since the pass that will allow us to contact each other will be very low on the horizon. I have been getting about 2 passes a day from the satellite AO-27, one usually to the east then the second passing more to the west. I've been steadily adding states as I hear them. I'm also making contacts via Echo (AO-51) which is very busy on it's nightly passes.

If it weren't for the listing on Heavens Above, I'd prob be lost as to when to listen for a satellite. For those stations that have sent me a QSL card, I will send out a batch as soon as my new ones arrive. The map above is a listing of those states which I've contacted (yellow) and those that I've received a QSL card from (green).

tags: ham_radio satellites awards

( Comments : 2 | Full article )

Arrow Antenna
radio : by Tommy - April 13th 2007, 11:31PM
This past Thursday afternoon I received my new Arrow Antenna. It's a dual-band (2m/70cm) handheld yagi antenna made from aluminum arrow shafts for making contacts with amateur radio satellites. What? You didn't know there were ham radio satellites? Yep, and there's more than one.

Using Heavens-Above, I can find when each satellite will be making a pass over my location as well as the angle and direction of the approach and apex. About an hour after I got the antenna, AO-27 was making one of its daily passes over me. I made sure everything was in order, set my radio to the right frequencies and walked to the field across from my house. Right off the bat I heard guys in New England talking with guys in Florida. Most everyone on the air was using a handheld with relatively low power (under 5W, which normally isn't enough to even get you across town). After just a few minutes I heard my chance to throw out my call. Right away I had two stations come back to me. First time to ever hear the satellite and I was making a contact on one. Unfortunately I didn't have a free hand to write down his callsign and I forgot it! Oops!

How does it work? Essentially the little satellite takes my signal and rebroadcasts it like a ground-based repeater does, only it's up - way up. Because it's up so high, it can rebroadcast my signal to most of North America. To hear me all the other station has to do is listen on the "downlink" frequency.
Really it doesn't take any special antenna to allow this, it's just this antenna is very efficient and easy to aim at just the right spot.

Continue reading...

tags: ham_radio antenna satellites

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Ham Tools
radio : by Tommy - April 2nd 2007, 11:49PM
I've been messing with some scripts lately that fill a couple of online niches for ham radio. Most of the visitors to Neodux might not find them very useful, but I'm linking it here for posterity and to explain to any visitor looking for ham radio information what they can find.

At the moment I have 3 tools up. First is a script that fetches the number of ham radio licenes issued in a given month and saves the data in an XML file. I then parse the XML files to create a table or graph. (Just nice to know for anyone curious.)

Next is a dynamic image that will create a map for any ham trying for a "Worked All States" award. It colors in states as you check them off your list. (This was one I made a couple of years ago, but I thought it should be included.)

Lastly, I have a notification script. When you take your FCC test, you have to wait for the FCC to post your information in their database. Rather than hunting it down yourself and checking daily for any news, you can put your name on the list to be notified and the script will shoot you an email when your name is posted.

I hope any ham-visitors find them interesting and useful. That is all.

update: I just added a second color to the WAS map. States listed with the verified tag, will turn green. This is to denote the states from which a QSL card has been received.

tags: ham_radio website

( Comments : 1 | Full article )

One Tube Regen Receiver
radio : by Tommy - January 24th 2007, 9:43PM
Well, it's taken me a while to make a post about this one. It was a goal of mine after I completed the simple foxhole radio and one I set out to complete over the Christmas break. I decided since the crystal set was the simplest radio to build, what's the next step? The one-tube regenerative circuit was the answer.

Lately I've been reading quite a bit about radio history and have read about the huge leaps in receiver technology with the advent of the "audion" or vacuum tube. A lot of initial growth in radio reception is thanks to this circuit designed by Edwin Armstrong while still a junior in college in the early 1900s.

I scoured the net looking for parts (chiefly the 3S4 tubes) and kept coming back to Borden Radio Company. Rather than drop alot of money on shipping from various sources, I purchased a kit from Borden. It also happens that he doesn't live too terribly far from my parent's so I was able to meet up with the owner/operator, Lance Borden, over the Christmas holiday.

I pieced the kit together in two evenings. The first evening was spent winding the coils and mounting the hardware. The next night was spent meticulously wiring the components as outlined in the directions. (Maybe color coding the wires would have made the instructions a little clearer, but I can't complain.) The radio worked right from the get-go. It's tuned for broadcast AM reception and works like a charm. As you can see in the picture it requires quite a few batteries to power the tube, but it is 100 times louder than the crystal set and much more sensitive. I've heard stations all over the nation on this little set. This evening alone I was able to quickly tune into WWL 870 from New Orleans as well as KOA 850 out of Denver, Colorado.

The controls are finicky and not really what the casual listener would want, but the sensitivity and simplicity makes it worth the effort.

Continue reading...

tags: radio kit

( Comments : 3 | Full article )

Worlds Simplest Radio Redux
radio : by Tommy - December 5th 2006, 08:41PM
After the success of my last post about my simple razor-blade radio (link here), I began work on making a slinky dipole. I tried to use 2 Slinky Jr. toys which I bought at Walmart for $.88 each. It didn't work as well as I had hoped. After quite a while of the coils sitting on my desk and playing with them, it dawned on me that I could easily use the small Slinkys as the tuning coil for a simple radio. I started to do the math to find the inductance of the coils. I measured 1.5" in diameter, which gave me 4.7" in circumference. I started to count the coils to calculate the open-air coil formula that I had used before. I stopped and thought, why bother? Just try it out!

I stretched the slinky to the length of the board I used on the old razor-blade radio and tacked it down. I made the proper connections, using a diode first. (Ground went to the 3rd prong on a power outlet, the antenna wire and clip was hooked to my 20m ham radio antenna, on my roof) I started with the diode because it is far more efficient than the razor blade, which equates to louder audio in the earpiece.

Right off the bat I was able to hear shortwave broadcast stations! Wilder still was my ability to receive the signal without having the antenna clip attached! I tried various points along the coil, finding I was able to hear certain stations better at different points on the coil. As before, I was able to hear local AM broadcast stations just fine, and various strong shortwave stations with a "shorter tap".
After listening with the diode for a few minutes, once again amazed at the simplicity of the setup, I switched to the razor blade setup I had used in the past and was just able to pull out the same local broadcast signal from before.

Continue reading...

tags: radio kit

( Comments : 5 | Full article )

LeTourneau Radio Club
radio : by Tommy - September 16th 2006, 02:50PM
Since I've been here at LeTourneau, I've had the chance to meet a few other ham radio operators. Problem is, none of us can have any substantial antenna setups in order to make many contacts, if any at all.

After speaking with a couple of guys, we decided to reorganize the LeTourneau Univ. Amateur Radio Club (LUARC) and host a special event station. LUARC was more or less disbanded once the old shack was torn down to make way for Glaske Hall.

Since none of us have been able to play on the air very much, our special event will be nothing more than a chance to get on the air and hang out. It just so happens that the day we chose will coincide with the opening of the Texas QSO Party. We will be meeting on top of the birm, in the center of campus. We will be putting up the antennas around 12:00pm on Saturday and operating into the early evening. Everyone is welcome to stop by and check out our setup or operate - no license is required.

If you're on Facebook, you can see our LUARC Special Event page for Facebook.

tags: ham_radio txqp

( Comments : 11 | Full article )

Worlds Simplest Radio
radio : by Tommy - August 3rd 2006, 12:58AM
I just finished making quite possibly the world's most simple radio. I had read a few HOWTOs for constructing a crystal radio. Some links offered the basic formulas for figuring the specs needed for the coil if you wanted to tune various frequencies. I purchased 3 spools of "Enamel-Coated Magnet Wire" from Radio Shack for ~$5, and picked up a crystal ear piece while at EPO in Houston.

After reading that just about any round object will do for a coil-form, and not having an empty toilet paper tube, I settled on an empty fish food container. It was small, compact, and just the right size - plus with the screw on lid, I can keep the antenna, ground and ear piece inside. I rinsed out the fish food residue, tapped 4 small holes with a drill bit and started wrapping the 22awg copper wire around the bottle. Every 5 turns I would wrap around a toothpick. After wrapping the bottle - which took a while - I ended up using about 30ft. of wire. (FWIW: my coil came out to be about 118uH) The toothpick wraps were then scraped free of the enamel coating to make antenna taps for rough tuning. (how this works) After ensuring there were no shorts along the coil body, I hooked up the 1N34 diode, ear-piece, ground wire and antenna and was greeted with some shortwave radio broadcasts. The first station I heard ID was WWCR out of Nashville, Tennesee, although there are plenty of others I can hear.

The trouble with such a simple receiver (no variable capacitor) is that there is little selectivity and the listener is bombarded by 2 or more stations at once - a mixing of all of the signals within a range of frequencies.

Continue reading...

tags: radio kit

( Comments : 102 | Full article )

radio : by Tommy - May 2nd 2006, 10:51PM
For about the past month or so I've been eyeballing PSK31 for ham radio. It's one of the newest protocols for digital transmissions for ham radio. PSK31 allows radio operators to send text messages back and forth rather than morse code (CW) or speech (phone). It's like chatting without a network connection.

Granted, many of the regular readers on neodux aren't ham operators, but it is a very interesting aspect of radio that begins to border line on hackable projects. In the event you ever wanted to start with PSK31, here's a primer. There are plenty of freeware programs to allow you to decode PSK31. All you need is an HF receiver, a verymodest computer and an 1/8"-to-1/8" stereo cable to hook the radio up to the computer. Install one of the PSK31 programs and you'll see text streaming in from current hams conversing over a whole array of topics. It's amazing that the computer is able to pull intelligable data from amid a whole field of static. I was able to read text from a signal I could barely hear, but could only see on the "waterfall" display. Another cool aspect is the lower power requirements of PSK31. 100W is overkill to work the world! To transmit you might need a slightly more advanced setup than a single wire, but nothing you can't build cheaply or conveniently purchase from plenty of vendors online.
While at the Belton Hamfest, I saw a DB9 model for Yaesu radios, I would've bought it if it would've worked for my Icom 706mkIIg.

update: I've now ordered a USB interface directly from Saratoga Amateur Radio which should be in shortly, and I'll post more on it after I've had time to break it in.

Also for the curious, here are a couple more links about PSK31.

If you really want to know, here is the PSK31 author's primer on how it works.

tags: ham_radio psk31

( Comments : 2 | Full article )

Belton Hamfest
radio : by Tommy - April 25th 2006, 10:48AM
I just got back from a weekend in Austin that started with the Belton Hamfest in Belton,TX.
I took a few items that I wanted to sell. My AT-100Pro autotuner wasn't exactly what I wanted. The interface was a bit more "clunky" that I would have liked. (I received it as part of my trade for the Icom 706mkIIg.) I also sold the Yaesu FRG-100 receiver, as well as my Yaesu FT-2800 2m mobile that I had in my car, (I bought it almost 2yrs ago at the same hamfest for $95, I sold it for $120!) and a couple of other things.

After selling I went shopping. I bought the LDG Z-100 autotuner which does the same thing as the other tuner, with one antenna and is a bit smaller; and it looks nice atop my radio. I also got the seperation kit for the 706 so I can mount the radio under my seat and have just the control head in view. On my way out I grabbed a few small 2-3W solar panels for $5. The convention center wasn't as full as I'd seen in the past, there were some neat items, but nothing remarkable. I did leave with some good gear and more money in my pocket than I came in with.

tags: ham_radio hamfest

( Comments : 1 | Full article )

Isotron 40 Antenna
radio : by Tommy - February 4th 2006, 09:58PM
I've finally got back on the air in the HF bands. After over 6 months of not having my radio reach any further than the local 2 meter repeaters (maybe 20mi away max), I finally have an antenna that lets me talk outside the state.

I bought a used Bilal Isotron 40 meter antenna from W6KIP off eham.net. I received the antenna after over a week-and-a-half long trek through the incredibly slow USPS shipping machine. That was on Friday, February 3. I assembled it and began thinking exactly how I wanted to mount it. I finally decided to mount the short "mast" (if you'd call it that) on one of the 3 vent pipes on the roof. I'll post a picture of it soon.

Part of my reason for using Isotron was the small size (only 22" wide). Looking at the antenna, you wouldn't even know it was an antenna, it looks more like a weather vane or birdfeeder. Being on campus, I didn't really want a very conspicuous antenna if I could help it. I haven't quite finished fine tuning the antenna, but I can do that as soon as I get my hands on one of the local ham's antenna analyzer.

I haven't made any contacts on it tonight due to an overwhelming amount of static on the 40-meter band. I've listened to a couple of nets, one on 7.2335 said that this is the worst noise they've had all month - what luck!

Update: Well, it turns out the noise isn't just on the band, although that particular night was particularly bad. It seems that the high level of noise (aka static) that I'm receiving is due to a local area thing. Most likely due to the power lines nearby.

Continue reading...

tags: ham_radio isotron antenna

( Comments : 1 | Full article )

Extra, Extra N5DUX is Extra
radio : by Tommy - March 16th 2005, 11:30PM
I just got back from passing my Amateur Extra test. This is the top of the licensing structure, I now have full privileges on the ham bands. It's not quite as big of a step from General to Extra as it was from Technician to General, in terms of privileges. There's just a bit more frequencies I can use now, and it feels good to have climbed the ranks. Granted, there's still plenty that I don't know, and plenty that I'm hungry to know more about.

The Extra test was just a written test (no code test involved), but the content is a bit more in depth and alot more technical than the previous tests. I had only really been studying in earnest, this week (Spring Break). I didn't just beat the snot out of the test, it was a nail-biter, much like my previous Morse test. I could probably do better if I took it again at a later date and studied more - but I passed, that's all that matters, and I'm happy for that.

tags: ham_radio license

( Comments : 3 | Full article )

N5DUX - Work All States
radio : by Tommy - February 28th 2005, 01:58AM

edit: I just passed my Amateur Extra class license test!
As most of you know, I got my General class license for ham radio. This allows me to operate on the HF (<50Mhz) bands. These are the bands that are what most people associate with ham radio: talking around the world. I have been logging my contacts in my log book and have decided to start trying for the ARRL Worked All States Award.
As you can see from the map, I have quite a ways to go, but it should prove to be a fun goal. This is only using the 20m band, which is what my dipole was contructed for. The limitation to this is that it is virtually dead at night.

As far as distance goes, I have logged contacts from my apartment with a station in the Cook Islands (in the South Pacific), the island of Trinidad (in the south Carribean) and 2 contacts in Canada (one in BC, the other in SK). At the SFA radio club station, I have logged various states, Canada, England and even Serbia!

While I'm on the subject of ham radio, I attended a "Hamfest" (ham radio swapmeet) this weekend in Orange, TX. I picked up some radio odds and ends, and an Extra Class study manual. I hope to take this test at the end of next month, but more realistically, it will be in the coming months. The Extra Class test (Element 4) is the highest level test for amateur radio, as well as the hardest and most technically challenging. By passing the test, I will be afforded access to certain portions of the spectrum reserved for other Extra class operators. Big whoop, I know.

update: still making contacts...

Continue reading...

tags: ham_radio awards

( Comments : 7 | Full article )

N5DUX now General
radio : by Tommy - February 16th 2005, 07:42PM
Tonight I passed both the written and code section of the FCC Amateur Radio Licensing tests to gain my General license. I had studied Morse Code off and on for the past few months. I thought I was ready back in December, but failed at that attempt. Tonight I passed, not perfect, but a good showing, nonetheless. I was sure I would walk away defeated once more, but after Army, AE5P, counted up more than 35 characters in a row, I was elated to find out I passed.

I also gave the written portion of the test a try and found out I remembered more of it than I thought - I hadn't studied since December! (...and that was studying with a slightly outdated book!) I passed with a 24/30, not as good as I'd liked to have made, but a passing score is a passing score.

It will take a few weeks for the FCC to process the paperwork to officially grant my General class standing, but in the meantime, I can still operate as a General license holder by appending "/AG" to my call. (I think it stands for Awaiting General)

I was really shocked, I was only expecting to eek by on the Element 1 code test, but, in the end, I got both. Very glad to have accomplished this.

tags: ham_radio license

( Comments : 11 | Full article )

NARC Club Website
radio : by Tommy - December 13th 2004, 09:11PM
I had connection problems with Echolink preventing me from joining the website discussion this evening. I would like to use this to voice my opinion.

All the webserver will need is PHP and MySQL (although, any other database platform would suffice). It is also important that we not sink a ton of money into this venture to begin with. As important as the club is to all of us, and any hams we may talk to, the general public is unaware that there is even a hobby called ham radio! In this vein, our server will not generate very much traffic, especially enough for us to take full advantage of even the cheapest hosting packages. We won't have hundereds of visitors per month. The main users of the site will just be the NARC.
If left up to me, I would design something off of the core of the code you see before you right now. I would use the same blogging technique. I am currently experimenting with neodux to see how easily I can incorporate an RSS feed for syndicated news headlines and alerts. This, among other things, will lend value to our site. As I stated, we won't have that many visitors outside of our group, but, for those that do visit us, we want them to leave feeling more informed and with "gee, I wish our club had that" feeling. I envision a utility that aids in operating practices as well as information dissemination. (Especially as it pertains to any activity surrounding Columbia disaster)

I hope this will fill you in on my thoughts about the subject. I ask for patience as we find the best solution for the club and not just amazing deal that turns sour. I would like to ask all members of NARC to be on the lookout for webspace that is...
  • ...ad-free.

    Continue reading...
  • tags: ham_radio website

    ( Comments : 10 | Full article )

    New License Plates
    radio : by Tommy - December 1st 2004, 11:59PM
    I just got my new license plates in today. Texas allows amateur radio operators to get license plates with their callsign on them for a whopping $2.
    I placed the order in the first couple of weeks of November and got them today.

    Some people say that ham plates are the epitome of being a radio geek, maybe so, but when I'm driving and I see call letters on the back of a car, I give a wave and almost always can talk to the other guy on 146.52MHz. It's an interesting way to meet other drivers when you're making a long road trip. It's just something neat to do, and it didn't cost me much of anything. So I like it.

    Mackieman sez: I got new plates too, but I opted for customized over my ham callsign. Behold the glory that is OMG BBQ.

    tags: ham_radio car license

    ( Comments : 2 | Full article )

    Slicing and Dicing Spectrum
    radio : by Tommy - August 14th 2004, 03:47AM
    I found this link from Slashdot, it's an article on how the electromagnetic spectrum is sliced and divided up among controlling parties. It mentions the FCC's latest partitioning of certain frequencies to Nextel. Also mentioned is the 802.11 "open frequencies", and others.
    The article gives a bit of insight as to how the current frequency partitioning mindset came to be, and offers alternatives.

    A good read for the curious.

    ...and another take on Spectrum rights and permissions.

    tags: fcc wifi

    ( Comments : 0 | Full article )

    ARRL Field Day
    radio : by Tommy - June 26th 2004, 03:09AM
    Today is the first ARRL Field Day exercise that I get to will participate in. Slashdot has a post about this too.
    Field Day is a chance for ham radio operators to check their ability to contact other stations without making use of commercial power (power company's power). Instead, ham groups band together, use generators and power their radios that way.
    Also included in Field Day is a competition between all ham groups. Each group tries to contact as many other ham radio operators as possible, gaining points for the distance, frequency and power level used. Each group logs their contacts and, in the end, sends their log to the ARRL for ranking.

    I volunteered to supply the Nacogdoches Amateur Radio Club with 4 laptops from my office at SFA to use as "logging stations" with some software the group purchased for this purpose.

    "Field Day" continues all day Saturday until Sunday evening, depending on when each group begins making contacts. Check with your local group to find their location and check out their stuff. 73!

    update: Field Day was awesome. Got to operate on almost all the General-class HF bands. I reached stations all over the US. (I even made contacts as far away as Hawaii and the US Virgin Islands, in the middle of the day!)
    The laptop setup was cool, had some problems, but it worked well overall. 3 logging stations with a 4th setup to monitor a map of the US which shows each region where a contact was made. We ran that to a TV so we had a quick, at-a-glance look at where we were making our contacts. The antenna array setup was also cool. Anytime you need a potato gun to hoist an antenna into a tree, is a good day.

    Continue reading...

    tags: ham_radio field_day

    ( Comments : 0 | Full article )

    Ham, anyone?
    radio : by Tommy - April 6th 2004, 02:02PM
    I went to Fry's on Friday afternoon with my girlfriend, I picked up a copy of Gordon West's book for studying for the Technician License for Amateur (Ham) Radio from the FCC.

    Those of you wondering what Ham Radio is or looking for more information should consult Google. In short, it is "short wave radio communications" or just a more powerful form of CB radio.
    The 2m band (144-148MHz) looks to be the first range that I will delve into. I urge you to check out Ham radio, especially the Technician license. 2-meter handhelds can be found on ebay for under $50.

    update: I picked up my radio today (April 11). It's a Yaesu FT-10R, 5W output. I bought it from a guy on ebay that lives about 15min from my parent's house. He also threw in a free external antenna. The radio is also modified to reach up to ~175MHz. I test next week. So far, so well.

    update #2: ...just installed my DTMF keypad for the radio. Makes frequency navigation much easier. I'm quite pleased, and the install was super-simple. Took me maybe 3 minutes to install. Awesome little radio.

    tags: ham_radio

    ( Comments : 0 | Full article )


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