Why bother building a rig?
This is a fair question when you can get rigs for a good price these days. Who would dare to believe that a transceiver can be built at home, with a receiver that can out-perform modern commercial equipment?
To further answer this question ‘why bother?’ let me tell you a story to wet your lips. This is my experience.
In the early 1980’s I was in bed with flu, thoroughly fed up, and my wife (the 1st that is) came home with a magazine called Ham Radio Today, the very first edition. Prior to this I was trained as an Avionics Technician with Marconi-Elliott, and then had some years designing hardware and software using microprocessors, mostly in the control industry (Paper and Brewing). Kids used to bring me CB sets to fix. They would either be faulty for genuine reasons, or made faulty with misuse. A common examples of this was they would connect it to their car power reversed and blow the fuse (They manufacturers would put in a large diode to blow the fuse, like a first warning). They would change the fuse a few times and keep blowing them, then in frustration put in cigarette paper, paper clip or a nail! If this didn’t catch the car on fire they would being it to me for repair, and I got quire a good name around mid Kent for doing this and earned a good bit of pocket money too… If you were not around in the late 70’s, understand, this was a craze and everyone wanted a then illegal CB. Most streets had a few antennas on the houses, and many cars had whip antennas. The airwaves were full and buzzing with local and DX, and you work work the world it seemed on 4 watts with a good vertical on the house, if you could get through the QRM that is! The rig fixing was easy, start by testing and changing the lowest impedance devices. AF amp, PA if tx was used, and work back to higher (less current) devices… Once a nice SSB rig came in and it was badly burned inside. It took a lot of work to fix, and the owner wouldn’t pay me, so I kept the rig. I tuned it up, and modified it for extra channels (240 with limitations) and a switch to flick in the little known ‘hidden’ channels. I could talk to people with similar access all over the place in peace from the noise, and yes, got hooked!
OK, Back to the OMEGA. After a few months Ham Radio Today started the OMEGA project, you could buy the PCBs or as kits, one board most months. I took it on and gave up smoking and used the money each week for buying components. It took over 2 years for me to get it going. Their 100W PA never did work well, and I used an alternative 15 watt PA. What advantages were there? Why bother?: I learned so so much about RF and radio building it. In fact I ended up working for Philips PMR radio 7 times over the next 17 years, as a consultant, contractor and permanent positions. My radio knowledge in design and construction, plus microprocessor skills were in high demand. It got me into an enjoyable career, and it could you too…
The receiver in the OMEGA is brilliant!, it is really quiet, and I could use it with phones on near full volume to pull in really weak signals. Try it on your rig is my challenge and see what happens!
The receiver is good (did I say that) and I believe better than even some of the best. I owned an FT902DM then, and it beats that, and really that takes some doing. I, like many, sold the FT902DM, and forever regretted it! I got another one 4 years ago.
Oh by the way, the receiver! Yes, try yours sometime. Go on 40m after dark on a busy night, and try to tune in a really weak signal that is close in to a S9+ station, and see if you can understand them. Actually, unless you have a really good receiver you may not even know they are there! OK, this needs a couple of rigs to test, one a really high quality receiver.
Another challenge. When was the last time you worked a station on SSB less that signal 3? (53, 43 or 33). In the late 80s I worked over 100 countries on my OMEGA using about 10 or less watts. One day I worked Australia, South Africa and North America for over an hour on 3watts, SSB, and the signals were all around the 53 mark. Not bad eh? (4 element HomeBrew Beam).
The Noise blanker is a really good Woodpecker killer, and effectively makes it gone. It is also good here with the electric fence and other large interfering spikes.
The notch filter is really good value too, a must on CW, or some ***** tuning over you on SSB. These were just a few advantages of the OMEGA. There were some down sides though, and for 30+ years I have imagined building a better one, and now have.
Some of the down sides of the 1980’s OMEGA:
- The construction involved many die-cast aluminium boxes with many PCBs inside (at lease 11), expensive feed through capacitors, and a lot of messy wiring!
- It was rather expensive, I think the bill for me was well over UK 300 pounds back then, and I had quite a few bits already. The learning experience however was priceless.
- The PA was a bit of a flop, the expensive transistors easy to damage, and it gave nasty motor-boating RF feedback to the rest of the rig. Something I never really overcame on powers over 10W.
- The VFO, while really good quality, had the tendency to be unreliable, and over time needed working on.
On the HamPi these issues have all been addressed and many more. There are now just 4 PCBs with components (plus a front panel and keypad). See the Features page for more details.
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