In this year’s ARRL Auction, I managed to score a 1985 ARRL Handbook to add to the collection.
It’s in pretty decent condition, although the binding is broken in about the middle of the handbook. Going to have to see if there’s a good way to patch or fix that.
This handbook probably would have first gone on sale in late 1984, so I would have been in the middle of my first year of high school when this handbook came out. Even as late as 1985, there’s still a pretty big section devoted to vacuum tubes and vacuum tube gear. Aside from an old broken radio that was in our basement, I don’t think I had encountered any electronics that used vacuum tubes back then (well, televisions perhaps, but those are a different kind of vacuum tube).
The table of contents covers radio topics you might expect for radio technology from 37 years ago.
Interestingly enough, there seems to be more on vacuum tubes in the 1985 Handbook than there is in the 1980 Handbook. At some point between the 1980 and 1985 Handbooks, the Handbooks gained a considerable amount of weightpages.
Might be interesting to go through the two and see what kind of content got expanded on with all the added pages.
The Digilent AD2 is pretty cool. The software lets you use the AD2 as an oscilloscope, signal generator, spectrum analyzer, and several other things.
Using the spectrum analyzer function made it pretty easy to set the IG-102 to a frequency, see what the actual frequency was, and then tweak the variable inductor coil for each band setting to tune the output to the dial setting.
The output of the IG-102 is pretty low though, less then 0.3 V peak-to-peak. I’m not sure if it’s supposed to be that low, but I expected it would be in the 3-5V range.
Well, at least it outputs something that’s reasonably well calibrated now. I suppose if I had to, I could build an amplifier to feed the signal into. I’ll see if there’s anything else I can do to get the signal amplitude up to where it seems like it should be. Maybe the IG-102 needs the tubes replaced as well.
The HQ-100 manual conveniently provides a table of the voltages you should be seeing at the tube pins. After replacing three of the tubes in the HQ-100, I went through and checked all the tube pin voltages and ended up replacing two more tubes (the 6BE6 and 6AL5 tubes). I didn’t have a spare 6AL5 tube on hand, but I discovered the VoltOhmyst VOM I acquired a while back also happened to use a 6AL5 tube. After pulling it out of the VoltOhmyst and putting it into the HQ-100, all the voltages at the tube pins matched the voltages in the table.
Unfortunately, I’m still not hearing any static or audio from the radio, so there’s more work to be done. The realignment procedure described in the manual calls for a 455 kHz signal source, so the next task will be to get one set up.
It’s a pretty hefty tome, and like previous handbooks, stuffed full of pretty much everything a person needs to know about amateur radio.
The hardcover Handbook also gets you the electronic version of the Handbook as well (I was sent a link to download both the Mac/Linux and Windows versions), which includes a ton of supplemental content for each chapter, project PDFs, and some software as well. What I haven’t seen in the electronic version (yet) is the insert between pages 15.18 and 15.19 giving a look at the evolution of the Handbook over the decades.
It’s a nice little review, starting with an interview with K1NKR and his collection of QSTs and Handbooks (sounds like he’s got all but two of the Handbooks…quite the impressive collection) and then highlighting changes in the Handbook by decade.
Looks pretty good on the shelf with the other Handbooks.
After spending a few days checking over things, I put the front panel and knobs back on, plugged the radio in and was greeted with some warm glowing lights.
The two lamps behind the frequency dial indicator both came on, and a nice warm red glow was coming from most of the tubes. Three of them (a 12AX7 and two 6BA6s) were dark though. Fortunately I had acquired all the tubes I needed for the HQ-100 at past hamfests. After replacing the three tube and applying power again, all the tubes were lighting up!
Next step will be to attach a speaker and antenna and see how well, if at all, the radio receives.