I'm getting older. Why do I say that? Because I've been feeling a huge wave of nostalgia for hollow-state and other simple radios lately. I think it started out when I stumbled upon a YouTube video from someone who had built a replica of the classic TwinPlex receiver. That reminded me of the Lindsay Publications books that I purchased at Powell's a little while ago regarding the TwinPlex and other simple tube regens. I also bought a handful of tubes and variable caps from Antique Electronic Supply around the same time, but they've just been sitting in my closet. With all of the life changes we've been going through in the last year, there just hasn't been time for this stuff.
That video got me longing for some glow-in-the-dark radio, so I remembered that I had an old National SW-54 receiver that my uncle gave me, somewhere sitting in storage. A bit of digging through the plastic totes got me to my prize, and I was able to fire it up around 1 AM this morning after a long day. The paper caps in the poor radio are probably bone-dry, but it still works (for the most part). The antenna was a hunk of wire about two feet long. I plopped myself down in the recliner, put the radio on the arm of the chair, and gave the dial a whirl.
There's something to be said for the subjective listening experience of these old radios. Yes, in every quantitative area of measurement, the new stuff made in the last 30 years blows them away. But you can't discount the intangibles that the vintage radios provide, such as the easy and smooth tuning across a wide portion of the band, the warm audio from the light (or non-existent) IF and AF filtering, and the simple "cool factor". (By the way, I really like Linux, but this makes me want to cry.)
The audio on the AM broadcast band was a pleasure to listen to, with the exception of some nasty hum that wasn't masked out by the carrier on weaker stations. I'm one of those people who likes to occasionally listen to sports or evil talk radio on the AM band, so I can see myself setting this radio up for every day use. The SW bands were not as fruitful due to my tiny antenna, but I did come across the usual hellfire-and-brimstone and Spanish language stations that one regularly hears there.
I did come across something kind of neat that I don't recall encountering before (but you must remember that I don't do much SWLing). The "CW" mode of the SW-54 is a bit of joke as far as I can tell, as there is no BFO in the radio (it looks like it makes the IF amp oscillate, but I can't tell for sure). Up around 9 MHz, the radio pulled in a very strong CW signal, something I didn't expect. After a second, the quieting provided by a carrier told me that it was actually modulated CW. Going back to the shack, I found the signal on 9.110 MHz, and a bit of searching on spynumbers.com showed that this was an M8a, or a Cuban numbers station delivering 5-figure groups in cut numbers. It's nothing particularly rare, but sitting in the dark, late at night, listening to my 40s vintage radio, I was transported back to the radio days of the past. It reminded me of being a kid and tuning the big, giant, console radio at my grandparents' house, and discovering this whole new world of the shortwave bands. It reminded me of being a nerdy teen, staying up late on Friday night to try to capture some exotic new signals and rare DX on my Radio Shack DX-440. It has strengthened that link to our history, when there was still magic in our radios.