Extended use of the beam finder

[jerry507]

My daughter knows how to turn on my tek 2215 and has now discovered the beam finder button. Should I be concerned with the possibility that she may hold down the beam finder for as long as 5-10 minutes continuous?

[Zbig]

That's a bit strange thing to ask Assuming she is too young to be just told not to and is just free to roam through your lab, shouldn't you be more concerned about her, I don't know, taking a soldering iron and poking her eye out or something? Well, unless you have all of that already covered, of course... Still kind of a weird question to ask, though. Maybe just unplug it or use a switched power strip when you're not using the thing?

[jerry507]

The floor plan of my rental house doesn't easily allow my main desktop computer to be in my workroom, so that's all downstairs on a high bench that she can't get to.

Normally I don't particularly care that she turns it on and messes with it, she's very very interested in it which is great. I'm just concerned about any damage to the phosphor that may occur if the beam is left focused on a point for a reasonably extended period of time. That isn't a normal operating mode for an oscilloscope. If it turns out to be a problem, I'll unplug it. The question is, is it really a problem? A good question for a forum where people know some very esoteric things

[mikeselectricstuff]

I think the finder just clamps the supply voltage, so unless it's bright enough to cause a screen burn I can't see a problem.
XY mode would be more of an issue

[tom66]

I thought most scope beam finders had a very blurry focus - at least that was my experience...

[aargee]

Ahh young children (I assume).

I remember the day my son found the power door lock switch in the car and did some long term stress evaluations on the door actuators, until the circuit breaker went. He was then locked in the car, the door key switches also relied on the electric lock actuator (probably an accounting over engineering design), it was almost to the break the glass to get in point when the CB reset itself, whew - yes a thermal CB.

I agree with Mike, I think the beam find won't cause burn in, unless she sits there for a few days holding it down.

[jerry507]

Awesome. I just switched it to auto trigger so if she leaves it on I can see so and won't worry about it. Children are awesome, but they really do expose all sorts of issues you never really thought of before... Thanks guys!