Rigol PVP3150 probes not adjustable? - Page 1
Forum section: electronics / testgear

author: wdonders
author_rank: Newbie
timestamp: January 13, 2023, 11:30:44 pm
content: Got my new Rigol DS1102Z-E today.It seems that the provided PVP3150 probes are not adjustable?The adjustment hole is there, and the tiny flathead comes in the bag, but there is no notch for the flathead to grip onto.. can't see a slot even with a loupeI don't think my probes need adjustment though, the square wave looks great so I suspect the probes came pre adjusted with my unit? Does that makes sense?(..and after adjusting Rigol just grinded the little grove flush which should be visible in the hole..?)

author: wasedadoc
author_rank: Super Contributor
timestamp: January 13, 2023, 11:55:38 pm
content: Photo please.

author: mwb1100
author_rank: Frequent Contributor
timestamp: January 14, 2023, 12:05:08 am
content: The PVP3150 user guide instructs you to compensate on page 2:-https://beyondmeasure.rigoltech.com/acton/attachment/1579/f-78ea846c-3d0e-42e7-b081-1da54df02d66/1/-/-/-/-/PVP3150_UserGuide_CN%26EN.pdfI'm guessing you got a slightly defective probe (or set) and are lucky that it appears pre-compensated. Or you're simply not seeing the screwhead that allows compensation correctly. They're tiny buggers.

author: srb1954
author_rank: Super Contributor
timestamp: January 14, 2023, 03:49:17 am
content: Quote from: wdonders on January 13, 2023, 11:30:44 pmSeems very unlikely that the probes were precisely pre-adjusted for your scope. Not only would the probes have to be adjusted to match a scope input but each scope input would then have to be precisely adjusted to the exactly same capacitive loading, over all input attenuator ranges, so that you could swap probes between inputs and still maintain the correct waveform fidelity.Then there is the problem of drift of the probe parameters over time and temperature. Even the highest quality scope probes seem to require occasional readjustment to obtain optimal performance.

author: Njk
author_rank: Frequent Contributor
timestamp: January 14, 2023, 04:48:08 am
content: The probes that came with my scope a year ago are all adjustable. Rigol provided five of them instead of four, to satisfy me better. But what if later they did "optimize" the design further, removing that capability? It'll be interesting to see the images.

author: wdonders
author_rank: Newbie
timestamp: January 14, 2023, 08:27:39 am
content: Quote from: mwb1100 on January 14, 2023, 12:05:08 amYeah, I've seen the manual.Both probes are exactly the same, I fiddled around with it for 10 minutes, there's definitively no groove.Hope I can make some photo's, I don't have a digital microscope, and the holes are pretty deep that my camera might not focus.

author: wdonders
author_rank: Newbie
timestamp: January 14, 2023, 08:50:19 am
content: Well, did managed to take some photographs with a cheap USB endoscope.Difficult to see, but you would think you're seeing something like a slot, but really, it's flat, like it's filed flush.(Also, the 'knob' is brass and lays deep in the hole, almost at PCB level)

author: mwb1100
author_rank: Frequent Contributor
timestamp: January 14, 2023, 10:27:14 am
content: In the photos the probe is set to 1x. if you're trying to compensate the probe at that setting, it won't have any effect. In the 1x setting the compensation capacitor is shorted out.See the following video at 11:30:

author: wdonders
author_rank: Newbie
timestamp: January 14, 2023, 02:42:14 pm
content: Indeed on the photo the probe is at 1X, but when I was trying to adjust it, it was on 10X.There's simply nothing there to turn..?Can some Rigol owners check if their PVP3150 probes look different than mine?This is so weird..

author: skander36
author_rank: Frequent Contributor
timestamp: January 14, 2023, 02:49:26 pm
content: Indeed. I has the same problem but the truth is that you need to use only the screwdriver that came with the probe.This has two heads. Only the litlle can adjust the probe. You must inser carefully, put the probe on 10X and rotate very easy. The variable capacitor inside the probe has an elevated edge that prevent using a bigger screwdriver.

author: Njk
author_rank: Frequent Contributor
timestamp: January 14, 2023, 02:51:13 pm
content: Quote from: wdonders on January 14, 2023, 08:50:19 amMine are looking similar. On your images, the slot for screwdriver can be clearly seen. The only difference is that the plastic that surrounds the metal part is green, not blue. That hardly can be the cause. See the message above.

author: wdonders
author_rank: Newbie
timestamp: January 14, 2023, 04:24:07 pm
content: I've cracked the puzzle!Seems that the small plastic screwdriver is not a sharp enough flat head to be able to feel or grab the slot. I pulled out my smallest metal precision screwdriver and voila, I can indeed feel the slot and turn itProblem solved for me now, plastic rubbish thing is going into the bin..Thanks for helping out!