how do i test a neon indicator light?

[methodofcontrol]

i've got a power light in my ampeg VT40 that won't light up. i have a replacement bulb pulled from another V-series ampeg, but i'm not sure if it works. so i don't want to switch the known bad one out for a potentially bad one. i would like to test the pull-out i have, how do i know if it's any good? can i use a 9-volt battery on the leads? or some other such simple test?

[Steve Conner]

Neons need about 100 volts to light them up, so the way to test it is to connect it to 120V from a wall socket. Be careful though, if you connect the bulb itself directly to 120V without a series resistor, it'll blow to smithereens. However, pretty much every neon pilot light assembly in the world has the resistor built in.

[Mouthurst]

I just went through it with a v2- after puting it to a meter-Now I dont know if its the same or similar but for interests sake-mine ran off ac, I just put it on a variac and brought it up slowly to 120, the thing is, if its a standby lite which runs off the b+ you must check the voltage dropping resistor or it will just blow again.
William