Isotech ISR440 Scope lives again maybe.

[roadrash]

This is the oscillopscope I recently bought to fix my Viglen computer monitor (on another thread). Well after being shown it turned on and a sort of pattern on the screen, I was assured by the seller it worked fine and just needed new probes (it came with none).
Well it didnt work and I spent a half hour on the phone with him trying things he suggested. In the end the dispay failed completely and the guy apologised and refunded me.
Well why I was waiting to get another one I thouight I have nothing to loose now and stripped the scope out completely inspecting everything. Straight away I noticed lots of signs of it being in a very damp place and eveven a bit of muddy dust in it. I could even see signs of water ingess on the PCB in some places and water marks & ring marks around solder pads and the solder gone grey. So I cleaned up the board & resoldered all pads like this and gave all switches a clean out with servisol switch cleaner. Well after I put it back together it seems I have it working. I have a line or dot depending on how I adjust focus and intensity etc moving fast or slow across the screen from left to right which I can speed up or slow down.
Does this sound like its doing what it should do?
I'm going to use the other scope to fix the monitor but this is a bonus if ive got it working again.

[stj]

Re: Isotech ISR440 Scope lives again maybe.

sounds good, you want the sweep fast enough for a continuous non-flickery line.
if you have a slow dot you can get screen burn.
connect a probe and hook it to the test point - then play with the input settings

[eccerr0r]

Re: Isotech ISR440 Scope lives again maybe.

If you have your time/division down below 50ms or so, yeah it would look like a dot moving across the screen... and it should be a dot if you focus it. Getting a line may mean an astigmatism problem but if you can focus it to a dot when the setting is 100ms/div that's what it should look like.

[roadrash]

Re: Isotech ISR440 Scope lives again maybe.

Had a sort of square wave form when trying to calibrate to probe. couldn't get it to stand completely still and it scrolled across screen.

[stj]

Re: Isotech ISR440 Scope lives again maybe.

that#s the trigger settings

[petehall347]

Re: Isotech ISR440 Scope lives again maybe.

twiddle the knobs like you know what your doing and see if you find one to get it steady .. some pull out for user calibrating .

[eccerr0r]

Re: Isotech ISR440 Scope lives again maybe.

Yes, not triggering properly.

On easy way to get that is if the trigger channel is not being used as the probe channel (wrong trigger input).

Dang, I loaned out my fully analog scope, need full pictures of other peoples scope now to refer to; my Tek 2465 is a bit more complicated than necessary compared to most other analog scopes...