Oscilloscope probes

[Bushbaby]

Can anyone recommend some good probes that are easy to calibrate. I bought some Autoutlet P6100's but for some reason I not able to use the tiny screw drive to calibrate them at all!!

Best Regards

Rob

[Amie]

Calibrate or compensate?

[Bushbaby]

Must be compensation using the little adjustment tool (mini screwdriver). The ones I bought seem impossible to adjust!

[ppppenguin]

Not all probes will compensate with all scopes. Some probes, often rather high bandwidth and expensive ones, will only compensate with scopes that have a rather low capacitance input. But I doubt this is your problem.

What do you see? Will the square wave not become square? Always overshoot? Or always rounded off?

[jimmc101]

Silly  question, I assume that you are using the x10 setting of the probes, the compensation has no effect in the x1 mode.
The compensation range for the P6100 is given as 10 to 35pF so it should easily be able to work with the 20pF input capacity of the PM3305.

Jim

[Bushbaby]

Thanks for your replies - the problem I'm having is the adjustment tool (which just appears to be a small cheap screwdriver) just wont fit onto the trimmer for some reason so that I can make just a minor adjustment to square the signal. I've looked using a magnifying lens and lamp and really cant see why the tool wont fit into the trimmer?? I'm thinking that that are just a cheap pair of probes?? What I'm asking is do you recommend any probes that can be easily adjusted as necessary with the supplied adjustment tool?

Best Regards

[Murphyv310]

Is the tool too wide for the trimmer?
I bought some decent probes last year and I had the same issue, I just filed the adjustment tool till it fitted. Got a near perfect square wave, don't forget to do the adjustment on X10.

[Murphyv310]

Hi
I just looked at these. They are very low priced TBH
Expect to pay ten times that figure for good ones.
These are decently priced.
https://uk.rs-online.com/web/p/oscillosc...s/7158733/

[Craig]

They are trying to mimic the Tektronix probe numbering system Pxxxx. From China of course.

They kind of sneak through Tek's ownership by using the number P6100 - because that is a missing probe number in Tek's numbering system. The nearest spec Tek one with switchable gain is the P6062B, long obsolete but utterly trustworthy. https://w140.com/tekwiki/wiki/P6062

[Murphyv310]

Hi.
I can understand why a novice would purchase a cheap probe. Many really struggle with scopes, probes, waveforms and operation of the scope. Some never get to grips with electronics and spending lots of hard earned cash on expensive kit never makes up for knowledge. Anyone I've mentored in the past I've told them not to go all out with top branded and expensive stuff till you are proficient and comfortable with what you are doing. Some give up and loose a lot of cash.
I'm sure if Rob gets the probes to adjust with the modified trimmer tool they will be fine for him as he's doing in the main guitar amps. The next stage is for him to understand what he sees on the scope screen and what to expect and what is clearly wrong, how to set the controls correctly and make a diagnoses of his problem.