How a Rotary (Angle) Pulse Encoder works. This is entirely different to the normal quadrature phase encoder you have used before.
A teardown from the Haefely Trench PESD 1600 ESD Tester.
Unboxing & Testing video of 16kV ESD tester:
Pointless video about toggle switches:
00:00 - This is NOT a regular quadrature rotary encoder!
02:08 - Tool Tip, Pin Vice
05:41 - EDC tool shootout, Victorinox MiniChamp vs Gerber Dime vs Olight Otacle
06:34 - We're in like Flynn!
07:13 - New Lab Jack for the Tagarno microscope
08:09 - Of course that's how it works
09:59 - Why is this not used more often?
12:29 - How it works
14:49 - Is there another example of this type of encoder? if not, why not?
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#ElectronicsCreators #Teardown

Hi By popular request, we're going to attempt to take apart this rotary encoder. this Oddball rotary encoder from the ha uh trench P600 gun that I've got and of course um I've done I'll link in the video If you haven't seen it of um, somebody eventually found you can still actually buy this. Let's check it out. Made by a company called Ebe a German uh company and it's basically a Dre impuls bler goofing that one.

but uh yeah, it is different to your usual um you know three pin phase quadrature um encoder that you're used to. You know these are a diamond dozen. This one actually goes in different directions so you can see that it's got um, three pins here and you've got like a single pole double throw um thing on either side and it only you can see down here. It only goes in when you turned in One Direction Only one side of it actually toggles when you move it and then when you go in the other direction.

So this one toggles. wiggle wiggle wiggle yeah back and forth. but this one stays still while you're going. One Direction and then when you go in the other direction, this one Wiggles and this one stays still.

It's it. it. I I Don't know how it works physically inside, so it's rather interesting. so let's tear it down.

Um, as far as I know, please leave in the comments. but I'm not aware of another rotor encoder that works like this. Was this like an an an old school um thing that was. You know this is like um early '90s early to mid '90s uh vintage.

but apparently like they still make it or whatever. So anyway, we're going to tear it down now. It doesn't look like it's going to be easy. We got four little plastic studs there that looks like a heat um welded like in place so we're probably going to have to drill those out.

I can actually get a blade down the side here, but it's not going to come out unless I drill those I Suspect? All right? Uh, handy tool for this is a Uh pin. Vie So um, just like a little handheld drill thing I've got on angle here so hopefully you can see it. that's not Optimum for me. Hang on.

I'll get my higher res glasses on I do actually have two um. pairs of glasses. these are my regular ones which are 1.25 times magnification. Not very much, but you know I I need them these days.

Um, and these are I got these. um my atet optometrist to give me these which are 1.75 times. So for close-up work they're just more better anyway. um some people have said like they got five times or something.

Jeez, that's like that's like Po Dexter stuff. Anyway, um let's let's go we we'll give it a go. And you want it oversized? Yeah it's hard when they're like round on top that's cutting away. There you go.

Yeah, it's going to take a bit. might if You get in there later with a smaller one. But let's let's try and get the bulk of it out. And of course, I don't care about damaging this now because I you can buy these for 6 each on eBay in Germany only in Germany and you can only find the data on this if you were a German speaker and you knew the correct German search term cuz the rest of the the rest of the interwebs.
the rest of my audience could not find it but a viewer in Germany went oh if I I in German this means this term I won't pronoun I can't pronounce it. but anyway, um yeah, they're able to find it within minutes of of knowing the correct German search term. So please, yeah, leave it in the comments down below. If you've ever used a rotor encoder that works like this where you only get where the contacts only work in One Direction Direction It would make decoding easier because you know there's a bit of a like art in writing your algorithm to decode your quadrature output.

Everyone just uses a library these days, right? It's build into Arduinos or whatnot. but for anyone who's had to and I've had to do this, had to write your own little algorithm that detects the direction of operation uh, on your regular quadrature output I Won't bother putting up details there you can Google a quadrature or phase based rotary encoder or just how how a rotary? Oh oh, look at that. That one just popped out. Oh look at that.

Wow. Wow, so that one was a bit how you doing anyway? yeah I did further damage. This it it. it only had the one pin broken I think it was this one here.

uh like it was just open and the rest the others were um and fine. and then although no, they're a bit dodgy cuz it's supposed to be a just changing drill bits. It's supposed to be a Um one where it. you know it just alternates back and forth like that.

right? just back and forth back and forth back and forth like that. but when I turned it in the direction that worked, the other one didn't seem to do it every every click. it just so. yeah, there was something something doing there, so let me change to a smaller drill bit here.

Yeah! so I think the whole rotor encoder was just just Cactus tongue at the right angle? always important I've actually got to put a lot of force onto that fingers. get quite sore after doing four of those. I was going to do an everyday carry shootout between my Victorinox mini champ uh which has might be my daily carry for like 15 years now. um and this, um, cheapy one I can't remember the brand.

um the no. it's the oite oite they make like torches and stuff and the Gerber I can't remember which Gerber it is but um yeah I I was going to do a shootout and then um I recently lent um my Gerber to Mrs EV blog. um she was using it to actually the bottle cap open to open some um paint tins and stuff. Never saw my Gerber again.

So I don't know what happened to the Gerber I was going to do a shootout. Damn it. Ah anyway, never loan your tools to to the misses so let's see if we can get some that knife in there does that? is that now going to lift up? No n oh hang on yeah. I can I see that move? This is not 3D but yeah yeah yeah yeah yeah, we got it.
Spoiler alert for the shootout I think the mini champ would have won. It's just it. it's far superior quality. Oh look look poppity Duda poppity Duda Oh oh look, there's a oh look look at that look at that.

There you go. it's that of course of course that's how it's going to work. Yes, here it is here. Sorry for the yellow background, that's a Post-It note cuz I've got a new stand for my Tagano microscope here.

so I can actually lift my Tano microscope up. Yeah, you can see it I can actually lifted up now. and yeah yeah, you can physically see it moving there. So I've got a um uh lab Jack I've got a lab I got a Vivo labjack I put this on Twitter and uh yeah.

So now now I can put like larger objects over there under there to focus. But the problem is is that now the minimum focus is not not at bench level. so I've actually got a So if I put this down here right down here like this, it won't focus. it won't focus it when it's zoomed in.

So yeah, unfortunately it's out of the Focus range. so I've actually got to lift that up now. But it does allow me to put the advantage is it allows me to put bigger stuff under there. Anyway, there we go.

put that on top of my Post-It note. Now yeah, of course that makes sense, right? You've got just a Leever that just flips between there and and there right? So there's a little plastic I'll show you the plastic cam in a second that goes in there and then just puts Force across there and boom boom boom boom it it just. it just switches between like that. so this inside of here as it turns must have like this thing can't obviously spin around but it must because of the shape of the the inner bit there must cause this to just burp burp back and forth between these two here so there doesn't seem to be anything wrong with the contact in there right? cuz the cont contct goes straight through to the pin un unless that's physically unless that's physically broken I can actually measure that I can Buzz that out.

Let's buzz it out. Yeah, it's still in play, but that was the good. Was that the good one? Ah ah yeah. there you go.

It's open right? so it's on there. Yeah, but it doesn't connect. Oh no no, it does actually connect. There you go.

So that pin. it's sort of like sitting in the middle. So I reckon is that just like worn out and it just sits in the middle? and it wasn't Yeah it I don't think yeah, that was bent I reckon that arm there was bent and it was never making contact. So as this thing spins around in here and is supposedly supposed to flip it over, it just didn't have enough Force to contact on there.

So the these contacts through here are okay. but I reckon that is that is what happened now if we try and place that in there. obviously that was sitting in there like that. So yeah, if you turned in One Direction it's just it's just there's something that goes in there the shape of that and that's just going to go boom boom boom as you go in.
One Direction and then boom boom boom like that as you go in the other direction. And obviously that was not enough. Force There was not enough contact on there cuz that that arm's intact. Everything's intact so you know.

I I Expected some sort of like surface contact thing like you'll get like rotary encoders surface contact but this one it. I You know it's kind of clever, but maybe maybe they're just not reliable and like does anyone else use this method or is it patented by this company I Don't know. Why is this not more popular? I I Don't know. Well well the Phas encoder thing uses uh, less uh pins but like you don't have to have the double throw um thing.

Yeah and there was this in here which unfortunately I never saw where that got to and there's another contact which has fallen down in there. so I'm not sure how that worked. Ah That's okay, that's a spring. That's the spring.

Okay, so the spring sits in there. it's all falling out. This is how the indent system works. that obviously sits in there somehow.

metal in here and they're all nicely goldplated and you know they're not going to like there's no wear on that. No, that looks pretty good. you know it doesn't look to be any major wear on that. So anyway, that is interesting huh? cuz this is called an angle pulse encoder.

So I guess we'll call it an angle pulse encoder right? It's very simple and I like it like there's no like surface contacts and you know cuz the usual encoder has a a brush on a like a contact wiping over a wiper going over a surface contact and this one's not that. And by the way, for those who wanted to know, uh yes, you can actually see through this thing so you can actually put a cleaner through and no cleaner didn't help me in this regard. There was this bar here so I'm not sure what that's doing. uh where that was, maybe that was cuz it seems too long to go as part of that.

so I'm not sure where that actually I don't know. leave it in the comments if you got an idea where that one went. All right. So I've put the shaft back in here and this is seems to be how it works.

It looks like this indent here uh, keeps a force on this plastic bit so that then goes into the shaft so I'll try and turn it at the same time. Sorry, this is not easy but so I'll try and keep a hold on this and you can see it. It's not very good, but you can see each each time it clicks over like that. it pushes it in and pushes the U the contact across that outer post and then when it slips back it the springiness will bring it back like that and it will contact the other one so effectively.

Like that's the normally closed one and that's the normally opened and it's just yeah, the slippage in the thing like that. So it's not like mine wore out due to like just the wearing down of the uh teeth in there the cogs. but yeah, it's I I Can only presume mine failed because of the like. the springiness in the metal just eventually went so you can really see hopefully in this.
like how the tolerance in this thing really matters. So maybe that's why I seemingly um, nobody actually uses this anymore because well, it's I don't know, leave it in the comments coments down below if you know of one of another encoder that still uses this rotary pulse uh encoder mechanism cuz it's really quite clever. but um yeah. I I just think yeah, the devil's in the devil's in the manufacturing detail and oh yeah, that is that contact there now bent or is it supposed to be like that I don't think it was that at the front start of the video.

was it oops, something's but yeah yeah, that is really clever isn't it? It's like the slippage in the in the Cog. Once it on it forces over to the contact and then once the tooth rotates past that bit there it slips back out and and it contacts back. So you get a brief contact over there and then it slips back to the normally closed and so on and so on and only goes in the One Direction If you go in the other direction of course it mainly swings over this side. it's pretty clever, huh? It's quite.

It doesn't have to move much right, but it's rather clever. But yeah, you can probably see how this is a little bit. Dicky maybe if you don't really design and manufacture it absolutely perfectly. So I don't know, leave it in the comments down below if you think this is brilliant and uh, I think it's quite.

uh, clever, but reliability compared to a regular uh wipe rotor encoder I don't know, uh, leave it in the comments down below. But anyway, hope you found that interesting. that's an angle pulse encoder I bet you've never seen inside one of those before. that is.

that is rather unusual. Yeah, as I said, leave it in the comments down below. if you know of one that actually works with this duel um, single pole double throw thing instead of like a phase uh wiper contact thing cuz it, it'd be easier to decode software-wise I think um, than a regular rotary encoder, a regular quadrature rotary encoder. but yeah.

I I Just think this is neat. It is neat. It just failed on me. So yeah, this one, uh, completely Kamuta and um, it's lucky I was able to find a replacement otherwise.

yeah, I would have had to cuz the software would have been expecting the the double pole action in there. so I would have had to like have a little micro that converts a regular rotary encoder or a toggle switch into that action of flipping depending on which direction you're moving it. Eh, it wouldn't have been hard, but you know it's it's just something that I didn't have to do in the end cuz I was able to get a replacement one and I got a spare one as well. So I got two replacement ones in the mail so hopefully um, that fixes it.
but there you go. That's an angle, impulse encoder and how it works I think that is quite novel. So yeah. Anyway, hope you enjoyed that.

If you did, please give it a big thumbs up. As always thr some comments down below website and Forum as well. Catch you next time.

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22 thoughts on “Eevblog 1573 – teardown: how a rotary angle pulse encoder works”
  1. Avataaar/Circle Created with python_avatars Fifury161 says:

    …but there are no kangaroos in Austria!

  2. Avataaar/Circle Created with python_avatars BRUXXUS says:

    What an outside the box way to think about how rotary encoders work! Performs the same task in a really cool way.

  3. Avataaar/Circle Created with python_avatars der.Schtefan says:

    It's not even weird that the manufacturer does not market it internationally; they probably have their 20 German customers that you never heard of, that make stuff for another 20 German companies that you never heard of, that then make stuff for another 20 German companies that you might know if you are in a specific field, that then make stuff for companies you know very well. Typically all small/middle-sized, family run since 1887, industrial manufacturing companies, with HQ in a small town in the black forest or "somewhere near Stuttgart" or Cologne. The company would probably not even think of marketing this internationally, since they can't compete with the low cost quadrature encoders.

  4. Avataaar/Circle Created with python_avatars gs425 says:

    The spring was FLAPPING IN THE BREEZE dave

  5. Avataaar/Circle Created with python_avatars John Wettroth says:

    Interesting- one thing that this design tradeoffs is that the backlash is not controlled. It depends on friction and how fast that little shuttle finds itself pushing on the contact. Quadrature encoders have well defined backlash important in positioning apps. This is better for a manual knob since its simple to decode. You can take some resistors and diodes and make a one terminal encoder- in one direction, the signal idles low and pulses high and in the other, idles high and pulses low- pretty simple to decode with just one pin.

  6. Avataaar/Circle Created with python_avatars Костя Костин says:

    doesn't a small spring with a tooth create a click on the gear?

  7. Avataaar/Circle Created with python_avatars Ludvik Tesar says:

    This rotary pulse encoder can probably be emulated by normal quadrature pulse encoder and one dual JK type flip flop chip (e.g. 74L73): The two outputs A, B of standard encoder would have to be fed into 74LS73 like this: A–>J1+K1+CLK2, B–>CLK1+J2+K2. Then Q1 and /Q1 goes instead of the two pins on left side and Q2 and /Q2 goes instead of the two pins at right side. This is assuming TTL logic is used, otherwise 4027B can be used.

  8. Avataaar/Circle Created with python_avatars Michael A. Covington says:

    I think you'll find the +1.25 and +1.75 numbers describing your glasses are not magnification. They are the reciprocal of the focal length in metres. So if your eyes can only focus on far distances, the first pair makes them focus to 1/1.25 = 0.8 m, and the second, 1/1.75 = 0.6 m. In practice your eyes can also focus closer than that, but the glasses enable them to focus even closer.

  9. Avataaar/Circle Created with python_avatars Riley Jones says:

    It seems kinda weird that the flat "contact bridge" isnt bound to one of the pins. It seems like the pressure against the "normally open" pin could pull the contact off of the "normally closed" pin

  10. Avataaar/Circle Created with python_avatars Thomas Unsworth says:

    Very clever. Not sure what pins are supposed to make or break as it turns.Looks a bit like a mini morse code key

  11. Avataaar/Circle Created with python_avatars Peter de Man says:

    First thing i liked about this video was the Bitcoin logo on the mic 😀

  12. Avataaar/Circle Created with python_avatars blargg says:

    I just noticed the pixellation of the mechanism in the video thumbnail. That's some funny clickbait there. Well done.

  13. Avataaar/Circle Created with python_avatars GordieGii says:

    The bent one goes opposite the white piece to produce the detent. The straight one pushes the white piece against the teeth.

  14. Avataaar/Circle Created with python_avatars GordieGii says:

    That is one of the standard way of sending control pulses to an industrial servo amplifier.

  15. Avataaar/Circle Created with python_avatars Arnold says:

    Very interesting. Maybe a interesting topic for another video: electronic torque measurement device, like from Amazon Aliexpress etc. Very curious of how they work and can be so acurate for that price.

  16. Avataaar/Circle Created with python_avatars Daniel Morin says:

    I would imagine this SPDT per direction would be easier to handle debounce, since you would only count the NO contact after switch had returned to NC contact, since the DT appears to be break before make.

  17. Avataaar/Circle Created with python_avatars Andrew_koala says:


  18. Avataaar/Circle Created with python_avatars DjResR says:

    That operation looks like fancy way of two buttons._

  19. Avataaar/Circle Created with python_avatars Robin Jacobs says:

    I wouldn't say it's unreliabl:, it worked 20 years

  20. Avataaar/Circle Created with python_avatars Fluxkompressor says:

    A long time ago I was working for the automotive industry R&D, blasting climate controls with an ESD gun very similar to yours
    Some batch of these climate controls had a problem with their encoders. They failed at 10kV I believe.
    I could not measure anything and wondered how on earth a simple switch contact could be damaged by an ESD pulse. I opened one up and found out they were optical with very complex light pipe action going on inside. Tiny little things with just about 10mm on each side. And sure enough after knowing what to measure I found out that one of the Phototransistors was open
    They had like a backplane with the active stuff and lightpipes leading to that backplane (probably to avoid ESD problems … yikes) You could also take one functioning phototransistor out and replace it from another unit. I made a bunch of projects using these "refurbished" encoders

  21. Avataaar/Circle Created with python_avatars T. Lang says:

    If I remember correctly I had a similar thing in a kit for a model railroad transfer platform controller. I think it was from ALPS.

    Oh, sorry – that one was a quadrature encoder, and one of the best…

  22. Avataaar/Circle Created with python_avatars says:

    Long sprint pushes the white part against the cogwheel, the other shaped spring pushes against the cogwheel from the other side so the clickety ratchet action is balanced and smooth and probably to ensure a full step is made and the whilte part stops centered.

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