So I’ve followed QRP homebrew projects for quite awhile now and have done my share of kits from QRPKits and other vendors but I’ve always wanted to “scratch build” a radio, the idea of ALL of the construction and design being up to me to be more appealing… but mostly I’ve wanted the learning that comes from the mistakes and risks of homebrew.
So you might think “risks” is kind of a silly word in what amounts to a hobby, but even in a hobby I think that we as humans avoid failure and that keeps us from experiencing a kind of victory over inactivity and a kind of fear.
Great guides in homebrew are the host and co-host of Soldersmoke, William Meara N2CQR and Peter Juliano N6QW. Through their exploits and adventures I was emboldened to try my first Manhattan style build of the Mighty Mite transmitter, and after some trials I got it going and had my first success.
My next project was going to be a bit more involved, so I chose the first project from Experimental Methods in Radio Frequency Design, an excellent book or dare I say the Bible of Homebrew. The project is the IC Based 7 MHz Direct Conversion receiver. I gathered the parts as I could from junk box and my parts drawers and when I was ready I started building it during spare moments last week. Some of the photos are below and they chronicle my progress, set backs and headaches. I continue to learn and as of this writing the radio does not yet work but I am undeterred. So if you wish follow my stumbling and learning and please don’t take me as any kind of guide but perhaps just a fellow traveler. Thanks and 73, Dave / W2DAB.
The beginning, laying in the NE602 and the LM386, soldered directly to the mePads.
The fully populated board, which turned out to be non working due to overheating of IC chips, later I soldered in chip holders and it worked better but not fully. Below is a link to a video which has some rather pathetic sound, more to come later.
There’s something in the ham spirit that is respectful of old technology and also willing to rejuvenate equipment to see another day of service, kind of like getting the last bit of toothpaste out of the tube. I love the idea of Packet Radio, a network of radios able to bypass the great internet to form their own bonds through primitive gateways and Packet BBS’s they hang together to form a tenuous alliance that will spring into service should an emergency require it. It was with these thoughts that I acquired an old AEA Pakratt 232-MBX Packet modem off eBay. The description was of a SK who’s estate was up for sale. I recently put a new Yaesu FT-2900r on my work desk for idle moments and I wondered if I could set up a packet station with my new mobile transceiver on 2 meters.
So after winning the auction the unit made it’s way to NYC to my humble apartment. I had the challenge to put together the necessary cables, software and other settings to get this unit working again. The Pakratt is no ordinary packet modem, it’s a wonderful multi-mode Data Controller capable of Transmit and Receive of Packet, Baudot and ASCII RTTY, AMTOR, Morse Code, HF Weather FAX and Pactor, as well as receiving NAVTEX marine broadcasts, TDM and Bit-inverted Baudot RTTY. With all of that you wonder what this kind of unit costs. The new updated model costs around 600. but this slightly over the hill but still serviceable model was had for about 25. bucks.
Now the connections needed for operation were power 12 – 16 volts, I definitely had some wall warts around, that was not an issue. Then the computer connection was an old serial cable, this I needed to order from an industrious eBay seller how makes the cables for these old Packet dinasaurs. The link to the USB Cable on eBay is here. The cable worked without a hitch! Next up was the radio cable on the back of the Pakratt to connect to my new Yaesu FT-2900r. The Timewave company (contact:”firstname.lastname@example.org”) was really great about providing one of these old cables (A shielded 5 conductor Radio Cable to connect the PK-232 Radio 1 or Radio 2 Connector to your radio data jack.) to me for $8.00 or so, combine that with a 6 connector RJ12/6 mic cable (I got my from Amphenol, and all I needed were the pin-outs for the connections and my own notes to solder my own radio cable.
Yaesu’s FT-2900r packet diagram was pretty simple, here.
Timewave (AEA’s) diagram showed the TNC side of the connections and I made up a little ammended diagram that showed the colors and wire numbers to dispel any confusion once the solder was melting.
Now that last piece of the puzzle was what software was I going to use on the Mac for making my connections. I First tried ZTerm but when I connected after entering my settings and I was getting doubling on my keystrokes so everything I entered had twice the characters, that was no good. Then I found CoolTerm, what a terrific program… worked flawlessly and was very user friendly.
Now if you’ve never worked with packet modems you basically go through three phases. After double checking all connections, you first check the Pakratt with it connected only to your computer with something called a “loop-back” test. You connect two wires and the modem talks to itself, in this way you confirm the Pakratt is functioning as it should minus any outside connection issues. The second step is to hook up and turn on the 2 meter radio. Receiving packets is easy to check if you put it on the frequency for APRS and listen. The last phase is to make a connection of my own.
LIMARC is a wonderful radio club here in the metro NYC area, fortunately for me they still operate a fully functional Packet BBS, where you can connect and access other Packeteers / Amateur Radio enthusiasts and share messages and other files. The whole experience felt very 1990’s and America Online, and the packet noises almost sounded like the old phone modems hooked up to my 6800 series Macintosh.
So, what did this experience teach me? 1. Packet is NOT dead, OK it’s very much in retirement but the old guy can still dance with his walker. 2. Old equipment does NOT mean junk, if you are patient and willing to put a couple of hour in on a weekend you can revive this stuff. 3. As a radio amateur there is ALWAYS value in having an alternate path of communication. I’ll enjoy many hours of working PBBS’s and other digital modes and all for a fraction of new equipment.
Thanks to Randall at Timewave Inc. for his help with cable names and numbers and shipping out what I needed fast and thanks to LIMARC for hanging in the Packet age long enough for me to enjoy it as well.
After some work to figure out what was going wrong with my Michigan Mite MIte I finally have it running and by that I mean oscillating. As it turns out I had used the wrong coil formula and when I rewound a new coil and oriented it the way Pete Juliano suggested I was home free.
I really am so excited that home brewing can be this accessible to a novice builder like me and I’ve learned a lot in the experience.
I may try a 20 meter Michigan Mighty Mite next, but for now I’m going to bask in my success and fit this rig to a contain and to proper connectors and use a real key next.
Here’s what I picked up in the way of tribal knowledge:
1. Orient the coil with the short tap towards the copper board
2. Connect that L1 coil lead coming off the bottom coil wire toward positive power.
3. Using an alligator clip as a heat sink is not a bad work around if you don’t have small transistor heat sinks. (The 2n2222 gets very hot).
4. When winding the coil it helps to use masking tape to secure sections of the windings before they have a chance to unravel.
5. QRP radio gear is a team effort, I loved having people to bounce my questions off of. This is really the best part… there should be more homebrew clubs.
So without any more thoughts the video is below, keep in mind I am tapping two wires together and don’t have a proper key hooked up yet.
Today I can celebrate the oscillation of my Michigan Mighty Might, at least I hope that’s what I am seeing here.
This story starts with two great guys in the QRP/ Homebrew movement, Bill Meara N2CQR and Pete Juliano N6QW both of whom have been on the Soldersmoke Podcast of late. I had it in my mind to do a small Manhattan style build of a small transceiver and on the podcast Bill and Pete were suggestion the Michigan Mighty Mite as it has a small number of parts and has a good deal of documentation out on the web. Master Meara was kind enough to put out a generous offer; to anyone that would build the Mighty Mite he would send a free 40 meter Color Burst Crystal for the project… free for the asking! I quickly jumped on this offer and was greeted by kind emails by Pete with encouragement to take it on.
Pete even contributed a pencil layout of how I could put the mePads on the copper board (figure 1 below).
I’d like to say I learn everything in the right order and never let my excitement take over but I have to say I went off quickly without using the layout and I built this, it didn’t work and I realized that there were two points where I made rookie mistakes and kicked myself… but every experience has a lesson and mine was not to rush too much. So I set out to build it again laying it out using the N6QW method. I even used Adobe Illustrator to refine Pete’s pencil layout with some wire color coding, the image below (figure 2) is what I used to help me build my second MMM transmitter.
This made is clearer and more idiot proof for me to connect the right component together, I didn’t put in the values as I was working from the pete’s drawing as well but I will do that and post a link to a pdf later.
So the next step as to draw a grid on my copper board using a quarter inch grid plane drawn with a soft lead pencil found in art supply stores (HB softness), this made it easier to lay down on the copper clad board. (fig. 3)
Next I glued down the mePads using super glue and a pair of tweezers, using care I didn’t glue my fingers together! (fig 4)
When I went and soldered down all the components it was a much happier and calm experience as I didn’t have to snake any surprise wires in weird places or re-solder anything. This approach had the added benefit of soldering each pad together without having to go back and melt everything again to add a forgotten component.
This last photo is of my finished board for the Michigan Mighty Mite next to an inexpensive Radio Shack General coverage receiver for SW listening.
My first home brew Manhattan style transceiver
To say I’m “Chuffed” is an understatement! You can’t believe the feeling of building a transceiver from scratch, there are no words adequate to fit the feeling of accomplishment. I’ve done kits before, including Dave Benson’s Rockmite but sorry the feeling of satisfaction is not there for me. I love the Manhattan style, the way you can see all the connections and components on one side and also the simplicity of laying something out. When I tuned to the crystal’s frequency I heard a tone, and felt a rush of excitement inside – almost like I was walking in the large footsteps of Marconi, Morse, Armstrong and DeMaw. I have definitely gotten the bug now. Many thanks to Pete and Bill 73
A short video posted on Youtube:
Meeting Rex Harper W1REX at MakerFaire NYC 2014
Today’s Saturday MakerFaire was most excellent indeed with Ham Radio making a good showing with the local Queens club HOSARC manning a booth and attracting a good number of Makers ready to get bitten by the Amateur Radio Bug. There are many reasons that Hams are sort of the original makers and hackers in this country but that is a different story, I was very interested to see at the same booth a QRP legend in the kit making business – Rex Harper W1REX of QRPme.com Rex’s products are known far and wide in the Homebrew/QRP community. I especially recommend using his MePads for Manhattan style building, they are pre-tinned and very good for keeping a neat and organized circuit board.
I briefly discussed the possibility of a DSB kit someday and he indicated that he has that on a back burner. The toughest part of being a success is that Rex doesn’t get enough time to build himself as he is too busy shipping out orders to all parts of the country and the world.
If you’re a new ham, consider building Rex’s Tuna Tin II, it is a very flexible and well put together kit and you’ll learn a lot about radio by building your own equipment.
I love MakerFaire, the Maker Spirit and the variety of things happening in the world of DIY electronics and other types of building. We are see a revival of making things here in the USA and I love that the Faire included people from all over the country, coming to Corona, Queens – once the site of a World’s Fair and a prediction of all that would come in the future. Our future is happening now and it is in the hands of everyman (and woman).
This week I am launching into a homebrew project that was recommended to me by a good friend in Vermont, I am referring to VK3YE’s “Beach 40” DSB Transceiver. Peter Parker/ VK3YE has put together a very nice little QRP Double Sideband Transceiver with a very modest number of discrete parts. The Beach 40 has been featured in SolderSmoke Podcast and website and is outline in several YouTube Videos done by Parker right from the beaches in Australia!
I haven’t built anything from scratch yet and I am going to do this in Manhattan style building techniques, which is somewhat ironic in a cheeky way as I live in Manhattan. It looks like I am nearing the acquisition of most of my parts, including the copper boards and little square things from the internet.
In building a homebrew rig for the first time. I do have some soldering experience with several kits two CW transceivers from Hendrick’s QRPkits.com and two Rockmite kits from Dave Benson/K1SWL at Small Wonder Labs. Dave has closed Small Wonder Labs, cheers to him for making nice affordable kits that let me cut my teeth so to speak.
I live in Manhattan as I said before and I don’t really have a dedicated bench so we have to see how I do on the dining room table, also I don’t have any sophisticated bench gear. All I have is a multimeter and a soldering iron.
I am very excited by this project because of it’s simplicity and also because I haven’t done a voice transceiver yet, the thing with CW rigs is that you need to know CW to actually enjoy using them. As amazing as Peter Parker has been at creating this rig I think that there are lot’s of gaps that can be filled in terms of documentation and mentoring. This would be an excellent rig to build for the new General class ticket holder that may not have a lot of money to spend on gear and also would like to go portable or even pedestrian as Peter Parker terms his walking excursions.
So may the radio Gods be with us and hopefully we can breath life into our own gear and as Bill says put the “spirit into the machine”.
Antennas always warm my heart
In this age of on-demand, internet/wi-fi and cable services it always warms my heart to see an antenna still above the roof lines. Why you ask? Because antennas now stand for something that we’re moving away from as a society. The lone antenna is all that was once needed to get content into our living rooms. A finite investment of thirty dollars and an afternoon paid us back many times over in free content.
Many antennas now are simply the remnants of old analogue TV, rusted relics of a bygone age. Broadcast networks and the FCC turned their backs on analogue in the name of better service and the modern age. Valuable bandwidth now freed up so the FCC can make some money and the companies vying for these resources can mint money.
What warms my heart are the antennas that are up for other reasons, newer digital antennas for Broadcast TV and ham antennas. What antennas equal are a desire to remain independent of the big block providers like Time Warner Cable or others here in NYC.
I recently took an afternoon to build one of those coat hanger HDTV antennas that you find on YouTube. I wanted to see if we could survive with only broadcast TV if we so desired but my experiment was dashed by poor reception due to the many large skyscrapers in our location that blocked out any possible signals we might receive.
I will continue to think about alternatives to all monopolies in my life because there is something very American about being less connected to all of these metered services that seem to extract more and more of our hard earned cash.
My new "Sixer", the Heathkit HW-29a 6 meter transceiver
I have come to own a fantastic little piece of amateur radio history! The nifty little “Benton Harbor Lunchbox”, a Heathkit HW-29 “Sixer”. It didn’t come with the microphone but hopefully I’ll be able to get one of those as well, if not I guess I can always try and wire something up myself from a different mic.
When I heard this rig was coming in I began to do a bit of reading on Heathkit and they really were an amazing company for the time, talk about DIY… they set a generation on the path to the “Knack” and probably launched more than one engineering degree. The company has changed hands several times and hasn’t made kits since 92’s ( http://goo.gl/hxfbT ) but at their height Heathkit made kits for just about every conceivable kind of electronic gear not the least of which was for ham radio.
There has been speculation that Heathkit may again make kits for the amateur radio enthusiast, I fired off an email to Heathkit’s current director of kits and I will update later if I get a response.
So… the great adventure begins with a new piece of gear, can I get onto six meters and make a contact? Stay tuned for more to come.
I have the usual collection of amateur radio books to help me with learning the technical side of the hobby, I recently purchased Danny Gregory and Paul Sahre’s delightful book ” Hello World/ A Life in Ham Radio”. As someone with a graphic design background I was chuffed that the production and the layout of the book was so beautiful and interesting. The book centers around the Ham Radio hobby of one Jerry Powell from Hackensack, NJ. One of the authors stumbled across Mr. Powell’s QSL card collection at a flee market and bought the whole lot, they didn’t even know what they were but they looked interesting to them.
The book is written in a breezy style that fits the visual layout and introduces the readers to Ham Radio vocabulary and basic operation as well as an overview of all of Jerry’s QSL cards and the ham’s that he contacted.
The book is more poignant when you are aware that Jerry Powell has been deceased for quite awhile and when many of the call signs are searched (I did) the calls come up inactive which probably indicates silent keys. Regardless, the book is really nice to have by my station as the styles and format of the QSL cards are so interesting. Much of the charm of correspondence of this type is that it is not done so much anymore with email, SMS and software.
The authors have put together a nice archeology dig of a ham’s life and it is wonderful to behold for us newer hams to behold, we can fall in love with all of our digital modes or technology but it is undeniable that the older guys have something we don’t… memories of a simple time when the hobby was the only “wireless”.
So, anyone out there still use QSL cards? I’d love to design one of my own if only someone would still exchange with me!