After many years of inactivity in ham radio, I decided to “go all the way” (while I still could) and get my Extra Class ticket. So in the middle of 2009, I bought the ARRL’s Extra Class study guide and started on page one.
And [Wow!] technology has certainly changed.
When I learned electronics back in 1963-1964, we studied vacuum tube circuits 90% and transistors 10% of the time. I built kits from Allied Electronics, Heathkit and Eico with a 100 watt soldering gun. And for years, my stereo was a custom design using 12AX7A (?) pre-amps with 6L6 finals whose plates would glow a dull red at full power. In the winter, you could heat the basement with that amp.
Today, the radios are going to digital software and parts are surface mount with 0.5 mm between the leads. Kit-building equipment starts with a large magnifier and circline-style lamp through which everything is done. Fine-pointed tweezers are used to position parts so small you have to hold your breath so you don’t blow them away or, worse, inhale them! Sticky rosin liquid flux is used as much to keep things in place while soldering as it is to make the solder flow.
Luckily for me, I’ve been involved with computers and software in my profession and the growing movement in amateur radio toward Software Defined Radio (SDR) technology is not an alien territory. On the contrary, I’m incredibly excited by the change because I’ve been trying to figure out just how we will make use of all the Symmetric (or Asymmetric) MultiProcessor (SMP/AMP) chips that are starting to become available, and now I know: All those processors are going to be parallel processing the waveforms!
So on a Saturday morning along with a dozen or more other applicants for various amateur radio tickets, I took the test for Extra Class. And I passed — by the skin of my teeth, mind you, but I passed!
The callsign I had not used for years as an Advanced class ticket holder, WB7UTR, was replaced (at my request) with a new, Extra Class-only combination, AE7CR.
And the Extra Class ticket also entitled me to apply for a vanity callsign and, when I spotted K7EDS (my initials are “EDS”), I applied for and received it.
But over all those years of inactivity, I had slowly sold or otherwise lost track of all my equipment. Gone was the lousy Heathkit HW-8 on which I made my first CW contacts. Gone was the tube-based Galaxy 500 (?) mobile rig on which I worked a station in South Africa while driving to work one morning — in the Phoenix summers, I had to stop transmitting at red lights to keep the rig from overheating.
Now, I’m licensed at the highest level but have no radios.
Let’s see, which kits should I start with?
My first effort will be a Juma RX-1 Direct Digital Synthesis (DDS) receiver and companion TX-1 DDS transmitter.
I bought non-integrated pair rather than the transceiver because the simpler design of each of the separate units would give me greater opportunity to understand the newer circuitry, and more opportunities to begin tweaking.
Surface Mount Parts on
Juma RX-1 Receiver Board
(Click for larger image)
I completed assembly of the RX-1’s receiver board last night and, when I stop writing this blog, I’ll begin soldering the surface mount parts to the DDS board. But that project also has some good old mechanical work to be done, cutting and labeling the holes for the controls and connectors as well as for the rectangular LCD frequency display. And the receiver needs a power supply once all of that is finished.
When the receiver is going, I’ll have to choose between playing with the software in the PIC processor that controls the DDS chip or moving on to assembly of the companion transmitter.
And when those are done, the PSK-20 kit is sitting there calling my name.
Antennas, tuners, switching, gel packs and fiberglass poles for portable use, paddles, keyers and add-on CW filters are all somewhere down the road, too.
So it’s time to turn on the circline lamp and warm up the solder station.
Eventually I’ll actually get back on the air again.