Some of the wonderful things about the amateur radio community is that it is seamless, universally friendly, helpful, and well equiped.
There is a HUGE following of vintage tubed gear and the folks with the knowledge and tools to restore gear are EVERYWHERE, willing to help with access to a vintage tube tester (no longer found in every drugstore) and autotransformers. And scopes and signal generators for that matter.
Find your local amateur radio club, attend a meeting, request help on a tubed project and it will be answered.
@Bill - further to Lissajous figures - many years ago Elektor magazine did an article entitled "Spirographics" - using a scope to make patterns like the old "Spirograph" drawing set which really just made complex lissajous figures. I had a Spirograph when I was a kid. I still have it somewhere (the article), maybe one day I'll get around to making one.......
w.r.t. "I'm pretty sure that this type of power light would be considered a fire hazard by today's manufacturing standards "
Actually, its probably the safest part of the scope, the bulb runs off the 6.3v filament winding.
On the other hand, the rest of the exposed wiring will have hundreds of volts on it while running.
You really need to take heed of the advice offered, regarding conditioning electrolytics before powering up these old valve powered sets.
Have fun with it anyway! Its probably only useful for Lissajous figures, or maybe with a microphone, or sonar, these old scopes aren't much use for troubleshooting modern electronics, as they are AC coupled, non calibrated, and have almost non existant trigger capabilities, with non linear timebases.
Caleb said "An interesting feature you can see is that there is a grid on the display. This model did not come with a grid on the display; someone actually added it after the fact. You can see the original without the grid here. The grid is a piece of overhead transparency with a circle of acrylic cut to fit in the rim. It is held in only by friction on the felt ring." But Caleb is wrong: I built an EICO model 425 from a kit in the late 1950s, and it came with the round plastic with the grid on it. No one "actually added it after the fact." I still have both the round plastic and the scope, which still worked the last time I turned it on (over ten years ago). The vertical and horizontal amplifiers have potentiometers to adjust their gains, so they are not calibrated. Although there is no triggered sweep, it was still possible to fiddle with the controls to maintain a steady trace. But I never enjoyed using this scope any more after I started using Tektronix scopes in the mid-1960s.
The MOST dangerous thing about these old devices is the lack of a grounded chassis and three prong grounded line cord.
I have seen Heathkits with a fused NEUTRAL, which would allow a shorted power supply to blow the neutral, then pass full current 120v to the metal chassis. Most pre-war radios lack isolation transformers, which added cost.
But, you can add a safety grounded cord, and the rewards (even the smell) of restoring these old devices are rich.
IIRC the long neck is required to get a good quality image,
A long electron gun is required to get a sharp colinear electron beam before it gets to the deflection plates. (otherwise you get out of focus spots, or oval spots that change with position)
The other reason for the length is to deflect the beam gently to improve linearity, deflection angle is proportional to deflection voltage, while the x position (on a flat screen) is tangent(angle) . If you use normal radio tubes , you only have ~ 100v of usable deflection voltage compared to say 1000v of acceleration voltage so you are limited to 1:10 deflection anyway, The other effect is that a fully deflected beam (at 100v) sees only 900v of acceleration, compared to 1000v on centreline
Shorter tubes have been made where linearity is not that critical.