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I bought a very old Philips oscilloscope some time ago (see my post. This is a Philips PM 3253). Although this Philips really has a lot of features, I cannot really use it well, since I cannot do good readings below 1 MHz because of the bad screen (focus problems, lines stay very long on the screen, or the signals are 'clipped').

Now I saw another one at a local 2nd hand site: Metrix OX8050

I was wondering if the probes between these two scopes (or actually in general in case this one is already sold) are interchangeable.

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  • \$\begingroup\$ Old question but the link to the product is down \$\endgroup\$ – pipe Jan 28 at 8:40
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Basic probes generally are interchangeable

Basic probes means probes with BNC connectors. Specialist probes, with extra pins and built-in amplifiers (such as differential probes or current probes) are generally not compatible with other brands of scope.

One thing to watch for is the input capacitance of the scope. Capacitance can vary between typically 10 and 15pF. Decent quality probes are adjustable, but not all of them can adjust far enough for all scopes. If you don't get them adjusted right, high frequencies will be distorted, and square waves may be slightly rounded or may ring.

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  • \$\begingroup\$ Thanks for the answer. I have now already 2 BNC probes (they came with the scope). And they have a 1:1 and 10:1 setting but that's probably not what you mean with specialist probes. My probes has one pin (and a small 'hook' extension) and also a small wire for ground. I cannot recall a adjustable setting but the probes look quite professional, so maybe I have missed that. I will make a picture this evening. And upvote tomorrow (I'm out of votes for today). \$\endgroup\$ – Michel Keijzers Jul 4 '17 at 12:37
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    \$\begingroup\$ Those sound like generic probes which will work OK on almost any scope. The adjustment is usually a small screw hidden down a hole in the plastic case of the probe or the BNC connector. See the section "Compensating an Attenuated Probe" on learn.sparkfun.com/tutorials/how-to-use-an-oscilloscope/… \$\endgroup\$ – Jack B Jul 4 '17 at 15:19
  • \$\begingroup\$ Thanks for that link ... and yes I have all those options on my probe :-) Sadly my current oscilloscope still does not give nice results (but I guess it's kind of broken, time for a new old-second-hand) \$\endgroup\$ – Michel Keijzers Jul 4 '17 at 23:45
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In general: yes the probes for these generic oscilloscopes will work across different oscilloscopes.

What you need to pay attention to is that the probes need the input of the oscilloscope to have an input impedance of 1 Mohm. I have never seen an oscilloscope that does not have this capability (or setting).

You can even buy "generic" oscilloscope probes on Ebay which are not that expensive and good enough for hobby use. I would not recommend them for professional use though.

Oh, and to get the maximum bandwidth (20 MHz) you must use 10:1 probes or set the probes to 10:1 if there is a switch. At 1:1 the bandwidth is limited to a few MHz. See EEVblog Scope probes video

Oh, also +1 for starting out with a good oldfashioned analog scope, none of that new digital rubbish (although I admit I have one and it is very convenient, or actually, too easy to use ;-) ). But for learning how to use a scope, an analog one is the best.

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  • \$\begingroup\$ I have probes with 10:1, and now you mention, maybe that is also a reason why I don't get good readings (I used 1:1 so far, I will check again this evening). Also I will upvote tomorrow (I'm out of votes). I will also check the EEV blog. And I use it with Arduino so mostly digital, but I have already had some signal problems, and a scope would be nice. So far the analog scope has let me down quite a bit, but I think I just had a 'bad one' and since I'm a noob I didn't see ...or maybe the 10:1 setting helps. \$\endgroup\$ – Michel Keijzers Jul 4 '17 at 12:40
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    \$\begingroup\$ Using the supplied, super long grounding wire with ANY such probe is guaranteed to have you measuring garbage once you go into 10s of MHz :) And really forget 1:1 probes, they are so capacitive that they drain more energy out of your circuit than a straight 50 Ohm cable @100MHz ;) \$\endgroup\$ – rackandboneman Jul 4 '17 at 15:38
  • \$\begingroup\$ @rackandboneman ok ... I have a 10x setting so I will use it ... but checked with my current scope (Philips) and still does not give good results, problem of the scope, hopefully the new will be better. \$\endgroup\$ – Michel Keijzers Jul 4 '17 at 23:57
  • \$\begingroup\$ I think my probes are good, at least I have the possibility to use 1:1 and 10:1, and I can compensate (not tried it, but will do when I have a better scope). \$\endgroup\$ – Michel Keijzers Jul 4 '17 at 23:59
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Another potential incompatibility is the readout pin (if your probes have one):

enter image description here

This pin is typically connected to GND via a resistance which defines probe type or mode (x1, x10 etc.) However, different manufacturers tend to use different resistance values for the same attenuation (e.g. Tek uses 10kOhm for x10, some probes use close/open switch for x10/x1), so you'll have to check if the new scope switches to the correct mode when a probe from a different manufacturer is connected.

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  • \$\begingroup\$ Thanks for the answer and the info... I bought another (simpler) oscilloscope (PM3110), the PM3253 is really unusable. I assume I can use my probes on the PM3110 (not picked up yet). \$\endgroup\$ – Michel Keijzers Jan 28 at 21:06

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