[Jeffhs]

I had a T/O exactly like yours about 25 years ago, though mine had chassis #5H40 (1951 vintage). Picked it up at a local hamfest for $25 or so. It worked at the time (wonderful AM and even SW reception using only the built-in whip antenna), but the cabinet was in terrible shape (falling apart, covering coming off in spots, etc). I finally got rid of it some time in the '80s (some time before I discovered AK--I didn't even get involved with the Internet until mid-1997), thinking that I wouldn't be able to find tubes for it if I kept it any length of time; those 1- and three-volt battery radio tubes were becoming scarce by then. Should have held on to it; it would be a classic by now. A true masterpiece of engineering and design by the former Zenith Radio Corporation of Chicago. (I have an early solid-state T/O, Zenith's Royal 1000-1, that I have absolutely no intention of giving up any time soon; it's built like a tank and works great even now, 49 years after its introduction, even though the dial cord snapped several months ago).

BTW, you should be able to find a set of original knobs for your T/O without much trouble. I see that style of knob (and even the brass "brights" inserts for them) on ebay every now and then, so if you keep your eyes open you should find some eventually. If push comes to shove, you could get a junker H500 and use the knobs from it; this would be a good investment for parts alone, including spare tubes. With an original parts source like that, you can keep your set working, not to mention 100-percent original, for a long time.

Good luck. They don't make them like your H500 (or the Royal series solid-state T/Os) anymore.