[quote]In x1 setting the wave is ‘over sharp’, that is, it’s the other extreme [/quote]This is very strange too.
[quote]and no adjustment or change in wave shape as you turn the screw on the probe a sin x10.[/quote]This is OK. The probe compensation adjustment is effective only in x10 setting.
[quote=“VEL255”][quote]In x1 setting the wave is ‘over sharp’, that is, it’s the other extreme [/quote]This is very strange too.
Hi VEL255,
Ok, now I would appreciate it if you might suggest my next course of action. Does the information I have conveyed suggest I have a faulty Scope? Should I exchange it? What would you suggest or does it appear not to be a serious problem?
Thanks,
Greg
To isolate the problem either to the probe or to the scope would you please take following waveform images.
Select x1 probe setting.
Select 1 V/Div and 0.1 ms/Div ranges.
In the generator select 1kHz square wave, 3Vpp.
Take images from both channels with this setting.
Change to 0.3V/div range.
Set the generator: 1 Vpp
Take again images from both channels.
[quote=“VEL255”]To isolate the problem either to the probe or to the scope would you please take following waveform images.
Select x1 probe setting.
Select 1 V/Div and 0.1 ms/Div ranges.
In the generator select 1kHz square wave, 3Vpp.
Take images from both channels with this setting.
Change to 0.3V/div range.
Set the generator: 1 Vpp
Take again images from both channels.[/quote]
Hi VEL255,
Here ya go … the parameter = image name
ch1_3Vpp.png
ch2_3Vpp.png
ch1_1Vpp.png
ch2_1Vpp.png
Well, it looks as if there is a slight issue with scaling but not too severe. I don’t call it too bad. This will not impact my use of the scope, but you can see that the x1 traces are “over sharp” on the 1V/Div scale both channels.
Also, the 1V/Div is under amplified, ch1_3Vpp shows best symmetry ch2_3Vpp is offset. 0.3V/Div is over amplified & just a little offset (both channels). It’s confusing. I think that’s right.
Greg
It seems your scope is OK.
Now it seems the probe is the problem. The compensation adjustment range is not large enough. This is strange. I try to find out the cause to this…
[quote]Also, the 1V/Div is under amplified, ch1_3Vpp shows best symmetry ch2_3Vpp is offset. 0.3V/Div is over amplified & just a little offset (both channels). It’s confusing. I think that’s right.[/quote]To minimize the offset you may do a calibration after the scope has been on for a while (e.g. 1 hour). Select Options -> Calibrate. The calibration values are saved and there is no need to repeat the calibration in the next session.
[quote=“VEL255”]It seems your scope is OK.
Now it seems the probe is the problem. The compensation adjustment range is not large enough. This is strange. I try to find out the cause to this…
Hi VEL255,
OK. Both probes deliver the same results. Both probes are Velleman, except one is 60MHz, the other 100mHz.
Greg
Hello all,
I know this may not be important to most unless you had the same problems I had. Vellman sent me two new probes and they calibrated perfectly.
Thought I’s share,
Greg