Oscilloscope Goldstar OS-9020A

[crystal]

Thanks to this blog I decided to buy an oscilloscope. It is my first scope, Goldstar OS-9020A. It's almost brand new, very hardly used if not at all. Inside I see nothing has been repaired, all the caps looks good.

How do I check is it working properly? Maybe 5 minutes after turning on whe it heats up a little bit the trace rotates for maybe 2-3mm, probably some cap is slightly off but I couldn't find any is wrong. Also when TIME/DIV is set to 2ms or less the trace become flickering, the more you go down the more flickering it is. Is it normal or not?

Also could anyone help me with service manual? It came with user manual but it's on German language and with original probe that came with it.

[rqsall]

I've put up a service manual for the Goldstar 9020G, which is pretty much the same except for the built in function generator the 'G' version has. http://fergus.7bits.nl/~ian/f9744ba778.pdf

I'm trying to repair a 9020A at the moment and found this after searching almost forever.

Good luck.

[crystal]

I've put up a service manual for the Goldstar 9020G, which is pretty much the same except for the built in function generator the 'G' version has. http://fergus.7bits.nl/~ian/f9744ba778.pdf

I'm trying to repair a 9020A at the moment and found this after searching almost forever.

Good luck.

Thanks man. It's really the same, same part numbers on the PCB.

[Howardlong]

Not sure from what you say whether you're learning how to use it, or have a genuine concern based on previous scope experience


Take a look at this video on how to check out an analogue scope http://www.eevblog.com/2013/08/03/eevblog-502-19-hameg-analog-oscilloscope/

Of you're unsure, shoot a Youtube video of what you're seeing and post it here.

[crystal]

That video is really just a teardown of that Hameg. Watched it, doesn't helped me a lot.

I am looking for some good tutorial video of how to use an oscilloscope and what to expect and how the proper functional oscilloscope should behave and work. I suspect during the learning all the faults it may have should be exposed. Right now the trigger section is somehow not all clear to me.

[Howardlong]

I'd say the first 15 minutes are generic and relevent to any analogue scope, sorry if I you felt I gave you a bum steer.

Did you do a video of what you're experiencing as I suggested? Maybe we can help you further.

W2aew does a superb channel on youtube for oscillosopes, but I am not sure that's the level you're asking for?

[crystal]

I just changed some caps in the power supply and It seems much better now, triggering works just like I saw on some youtube videos. Now it shows 100Khz from the de5000 very clear, before it was kind of a messy.

For anyone watch this in the future the caps I changed are c902, 903, 905, 906.