As promised, I made a bit of time before work to get the Tektronix 502A on the bench and powered up. It marred the surface of that bench but oh well. It already got its first battle scars from the HP signal generator in the background.
I used a Hewlett Packard 3310A function generator to provide an input signal. I’ve never seen a Tektronix oscilloscope of this vintage in action in person before and the descriptions out there of the traces being pencil thin are no exaggeration. The phosphor is a really striking blue and very intense, almost painful to look at if it’s turned up too high.
Both input channels work but the triggering doesn’t and both traces vanish whenever the trigger level knob is moved off the far clockwise range of travel. I don’t know if that’s due to user error on my part, not enough time running to get tubes and Nuvistors fully woken up after sitting idle for an indeterminate amount of time, or if the trigger section actually does have problems. Unfortunately, I didn’t have as much time to play with it as I’d have liked before leaving for work so it didn’t get a long run-in time to start coming alive with and I wanted to get some other test equipment spun up while I was down there.
But differential inputs! This is something that is going to be really handy for balanced line audio work so I want to restore it and find it a more permanent home on or easy reach from the bench.