My Scopes Accuracy?

[Tony3dd]

Hi all, I just took delivery of my first scope. It's an Owon SDS-7102. The first thing I noticed was that the accuracy wasn't that great. If I set my Korad power supply to say 15.00volt,  channel 1 will read 15.02, and channel 2 15.08. My multimeter will read 15.003. Why is it so far off? I have the system setup for X10 on both the menus, and the probes. Is this normal?

[SeanB]

Quite normal for a scope, which typically has an 8, 10, 12 bit ADC in the front end. This gives a poor voltage resolution, which is fine as the display is going to be only 256, 512 or so pixels high, so having more bits than you can display is not useful.

[Tony3dd]

Quite normal for a scope, which typically has an 8, 10, 12 bit ADC in the front end. This gives a poor voltage resolution, which is fine as the display is going to be only 256, 512 or so pixels high, so having more bits than you can display is not useful.

That variance between channels is also normal? I really like the scope do far. Nice bright needle sharp screen, good from panel layout, and pretty decent build quality. Got it for $365 brand new with free bag, and shipping. Came in just 3 days! The people at Saelig were great to deal with. The scope actually goes on sale Monday, but they gave me the sale price last week!

[iloveelectronics]

Quite normal for a scope, which typically has an 8, 10, 12 bit ADC in the front end. This gives a poor voltage resolution, which is fine as the display is going to be only 256, 512 or so pixels high, so having more bits than you can display is not useful.

That variance between channels is also normal? I really like the scope do far. Nice bright needle sharp screen, good from panel layout, and pretty decent build quality. Got it for $365 brand new with free bag, and shipping. Came in just 3 days! The people at Saelig were great to deal with. The scope actually goes on sale Monday, but they gave me the sale price last week!

Have you tried running the self calibration on the scope? That might help bringing the readings on the different channels a little bit closer. However, I don't think oscilloscope are generally designed to be very accurate, especially the lower end ones.

[TechJunkie]

My Atten does something like this but my Agilent does not. It may be just the resolution or something to do with the DAC's. Even though my Atten does this,it's still well within spec.

[Tony3dd]

Yes, mine is well within also. Saelig said it was normal.