"Dave" wrote in
news:Jwo0i.39373$KN6.7185@edtnps89:


"Dave" wrote in message
news:jQH_h.10486$KN6.6932@edtnps89...
I'd like to know what the minimum useful bandwidth is for an
oscilloscope to be used for general TV and audio equipment
troubleshooting and repair. I've stumbled across a 20MHz dual-trace
scope at a second-hand store, it appears to work and they only want $50
for it. The brand is "Leader" which I'm not familiar with. Comments?

When the scope is powered up, it has a white line which starts to cross
the screen from left to right. The line gets about halfway across, then
disappears and doesn't come back.

Does this mean the scope is disfunctional? I thought it should have a
steady horizontal line when it's turned on with no inputs.

That depends on how the triggering is set.

You could be set for single sweep. It almost sounds like that and a slow
sweep at that.

You could be set for triggered sweep and not have a trigger.

You need to play with a properly working scope for a while to learn how to
use it and then you can test a questionable scope.






--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

remove ch100-5 to avoid spam trap