Hi, this is going to be a quick video I know I always say that but anyway I'll do my best. This is in response to a thread on the Eevblog forum from it user Lyta Jizz and it concerns the Reigle probes that come with the new Des 1054 Z Oscilloscope and you've seen the review on this there the RP 2200 model. Here they're a nominal bandwidth Raider bandwidth of one hundred and fifty megahertz which is you know, reasonable for a 100 megahertz scope. But the issue he had was that he actually compared it with the RP 3,300 probes.

These are a nominal a 350 megahertz bandwidth pros and these come with the Rai Gold Es 2000 series scope which is a 200 megahertz scope see at 350 megahertz pros. With that which is more than enough but he had a He did a test comparison between these two probes and he didn't think that these probes were suitable although I actually affecting the bandwidth performance of the RAI Goldie's 1054 Z if it was you know, hacked after 100 megahertz or you bought the 100 megahertz model And here's a screenshot he did between the two and it looks drastically different. As you can see, the yellow waveform is the 350 megahertz probe. so he is suggesting that these Rygel RP 2200 series probes actually affect the performance.

Contrary to what I said in the video, I said that while these RP 2200 probes at 150 megahertz were really good enough and shouldn't affect the system bandwidth in theory, that wasn't quite right. but historically oscilloscopes have always come with the same rated bandwidth. probes as the bandwidth of the oscilloscope. So that's what I meant by.

You know, they're pretty good because you're getting 150 meke probes with a hundred megahertz scopes. So is it any good? Can we reproduce the problem that Lyta Jizan seen? Let's find out. So just a quick comparison of the specs here. This is the 2200.

This is the 3300 input capacitance is basically the same in that way. By the way, we're only talking about times 10 here. so seventeen puffs as opposed to a slightly lower sixteen puffs on the 350 megahertz bandwidth as opposed to 150 Meg. And of course, you'd expect the corresponding rise time to be different, but apart from that, it basically the same input capacitance.

And there is one difference to note between the probes. The 2201 is compensated at the probe tip. Here, there's a little adjustment, and the 3300 is compensated at the end of the cable. It's neither here nor there.

They just start different ways to do it. these high-frequency probes. It's most common to have them compensated at the connector end here, rather than on the probes. Just the way it is.

now. the ground leads are different lengths. This is the 3300 350 Meg probe is actually longer than the RP 2200 and that's going to make a difference if you're probing like that. We won't use those today.

We'll ignore them. That could be the source of Art my teachers problem, but he actually mentioned on the forum that his ones were actually the same length. So yeah, maybe my nope, just different than what he's got. But anyway, now I said before that it wasn't really right.

When I said that, well, 150 Meg probes won't affect the bandwidth of a hundred Meg scope. Not strictly true, but you know, like in the real world, it's like it's near enough. Like if you want to look into it, this isn't precisely correct. but what you need to look at is the entire system bandwidth.

And a lot of oscilloscope manufacturers your big ones will actually specify the intertidal system bandwidth based on the matching probe they supply and the scope itself. Anyway, if you want to add bandwidth together like this, ie. the bandwidth of the total system that includes the scope and the probe, then this is the standard form of adding to the giver: just one on the the bandwidth of the scope, one on the bandwidth of the probe, square those, and square root that one on, and you punch that in the calculator and you get around eighty 3.2 megahertz. But that's not going to be the true answer really, because it's all to do with actual rise times of this.

You know the probe and the scope and the signals and everything else. But if it's going to be ballpark, so adding 100 50 meg probe does actually reduce the bandwidth? Obvious Scope: you know, somewhat. possibly not nearly as much as this. But anyway, that's what happens.

So yeah, it is going to reduce it just a bit and you can never have too many scopes for a test. Let's go. So what I've got is the Rye Goldie's 1054 Zee And yes, it has been upgraded to the 100 megahertz bandwidth and I've got my row go up function GN here which is just generating a 1 kilohertz square wave and I have a matching Terminator here just so that we can probe a signal with an O and termination. So I'm going to use each probe here.

Yes, we're going to ditch these ridiculous antenna earth leads and we're going to use one of these probe 2 B and C adapters like this so we can get right on there and probe the signal. Let's give it a bill. So first up, the RP 2200 the probe that actually comes with the Rye Goldie's 1054 Sir, do you plug it in And yes, I have got my little adjustment tool gone in there and compensated that 1 kilohertz signal. Okay, so we zoom into that and we notice.

hey, look at that. we're getting a couple of Wiggly's on there that's going to be normal because of this. Functions you know may not be perfect, but got a little load mismatches. All sorts of things happen in there, but it gives us a good benchmark to actually compare probes to.

So although we're using our Times 10 probe here high impedance probe across our 50 Ohm Terminator here, it's going to make a difference because it has an input capacitance that we saw in the datasheet before that 16 or 17. Pico Farad's what it is, what it was. So even with our 1 Kilohertz signal here that it's not a low frequency signal we're measuring, we're interested in this. ie.

we're not interested in the 1 Kilohertz signal. we're interested in the high frequency component of that. So due to the input capacitance and slight mismatches and all sorts of things, we're going to see a wiggle like that Anyway, It doesn't. The actual practicalities of that doesn't matter.

We've got ourselves a good benchmark that's 5 nanoseconds per division, and that's pretty good. We just see a little bit of overshoot, a little bit of ring in there, and then it settles down pretty well. Okay, now we're going to RP 3300 probe. I've tweaked that with my tongue at the correct angle.

Okay, so that probes compensated and looky what we get. No problems whatsoever. It's practically practically identical to what we got with the other probe. And yes, we've got this exactly the same probing configuration there, so bingo, it's busted already.

The RP 2200 probe doesn't make any difference at all. so let's try some other scopes as a comparison. I Got the right old DSR 2000 series scope. This is a two hundred megahertz bandwidth, but because the bandwidth, of the scope is going to matter.

The good thing about this is that it does have a hundred megahertz bandwidth limit. So we've turned that on. And because each oscilloscope is different a different input capacitance, we have to go in there and adjust the probe for each and every one. So each probe we do on each different scope, we have to recompensate.

So there's our RP 2200. There look looks practically identical. Let's not quibble about any minor differences in there and you'll see that if we turn the bandwidth off, we'll get some higher frequency content in there because we're going to get extra ringing to do that now 200 megahertz bandwidth. But we're using a hundred and fifty megahertz bandwidth limited probe.

and now I've got our RP 3300 probe that's with no bandwidth limit. So this is a 350 megahertz probe on a 200 megahertz bandwidth scope. And of course we can put down our own. If you're on 20 megahertz, it's just gonna round it off like there's no tomorrow.

Look at that and there we go. Very similar to what we had before. So those two are. try go scopes with those two probes.

Very similar sort of pulse performance as it's called between the two systems and the two different probes. Now we're going to use the GW in stick GBS 2304 scope. It's a very nice at 300 megahertz input bandwidth I traded scope and we've got the RP 2200, hundred and 50 megahertz probe. Let's turn it on.

and the reason I chose this scope is because it has a hundred megahertz bandwidth limit. So there we go. There's the 200. There's the full 300 megahertz bandwidth.

not much difference between the full and the 200 megahertz bandwidth as you can see because we're only using a hundred and fifty megahertz probe here, but basically exactly the same performance as the RAI goal. Look at that and once again, every scope is different so we have to just tweak our adjustment Pop there. yes, tongue is at the right angle and we can zoom in on that. This is now our RP 3300, 350 megahertz probe and as you can see, examine basically very similar performance to what we'll get in before and we should see a larger difference between the 200 and I'm not a huge amount, but I think it is a little bit bigger difference than we got before because this is a 350 megahertz probe.

A bit of an Old Faithful scope Here, the Tektronix TDS 305 4 and excuse the dim screen Yes, it feeds with time. This is the RP 2200 series Pro compensated. This doesn't doesn't have a hundred, but it does have a hundred and fifty, so as you can see, the pulse response is a bit peaky. er on this.

Tektronix TDS 305 four. It's more similar to the GW in Stick in that respect. The Rygel's seem to have a lower roll-off response in that respect, but it's neither here nor there. We're comparing probes here and with the compensated 350 megahertz probe here.

quite similar response. So there you go. It's confirmed on four different oscilloscopes that there is essentially very little difference between the RP 3300 and the RP 2200 probes. And if you want to see what that looks like on the Tektronix MDO 3000, which is a one gig bandwidth scope, this is the RP 2200 probe.

Once again compensated. That's the full 1 gig bandwidth. You can see really really high frequency noise go all over there. It doesn't have anything close to the hundred megahertz our bandwidth.

The nearest it's got is the 250 megahertz. You can see some of that real high frequency content vanish. But effectively, the the lower frequency pulse response is. you know, very similar.

So there you go. That's it. And of course the 20 megahertz just rolls off. and this is the RP 3300 Practically identical.

Look at that. No problems whatsoever. I Think that's done and dusted the bloody annoying Tektronix one to four sequence. It's just a four nanoseconds.

What's that rubbish? To be one, two five. So there you go. I Hope I Cleared up my teachers concern that there was a significant performance difference on the Ts 10:54 said at a hundred megahertz between these two different probes and that the RP 2200 probe that came with this thing was. you know, somehow, no good.

Well, it's yeah, it's an okay probe. Nothing wrong with it when you do. what control tests like that? I Can't see a difference on my probes anyway. And of course, there are more are subtleties to actually measuring this.

I'm not going to go through and actually sweep and get the bandwidth of these, our probes and all sorts of stuff there's you know, lots of little nuances in actually doing things like this. but anyway, I think that's a fairly decent test under exactly the same conditions. These probes pretty much produce the same result given the hundred megahertz bandwidth scope. So 150 Meg probe that comes with it more than good enough.

Hope you enjoyed that. And if you want to skate jumping over to the Eevblog forum, catch you next time you.