GADGETS#8 - DIY PULSE TRANSDUCER

[@theGADGETSplaylist]

A piezo disc based tail pipe pressure probe build. Allows cylinder contribution analysis with automotive oscilloscope.

[@guussano]

God bless you, thank you very much for your teachings, what a pleasure to see your videos

[@theGADGETSplaylist]

Thank you Carlos:-) It pleases me that you're enjoying them and hopefully there's more to come!

[@jeffgrizzel9499]

Just finished ordering them. Thanks. Have a great day.

[@theGADGETSplaylist]

+Jeff Grizzel - If you want a head start on the in-cylinder pressure transducer, order this pressure sensor. They take a long time to come in. Select the 300PSI one. www.ebay.ca/itm/401232090642

[@mechanicmatt871]

I noticed that you drilled three small holes at the rear end, that's something I haven't seen on other home made pulse sensors, did you do it to help the piezo move freely, (without trapped air behind it) I had no idea the first look was so expensive. Thanks for sharing

[@theGADGETSplaylist]

That was the idea at the time. How necessary, I can not tell. There are alternatives to the First Look. And for WPS500 pressure transducers. Check out ROTKEE and AUTOSCOPE for their pulse sensors and in-cylinder pressure sensors (all well priced, IMO). Good options, especially in Europe. The pulse sensors are used RAW (no probe settings). The P16 and the Px35 do need PICO Custom Probe to be created. If you go with one of those, I can help with that. I've created them for HScope Probe Database also.

[@mechanicmatt871]

That is two names I hadn't heard of, I must have been living under a rock. Thanks for pointing in in their direction.

[@train4905]

A most butifull build sir. Steve from the uk

[@jenbry97]

Looks like you used a female bnc connector for the transducer. I'm assuming you have a male-male connector somewhere in the connection to oscilloscope? Nice work. Just finished this project and a few of your attenuators.

[@theGADGETSplaylist]

yes, I have 1 meter cables with male BNC at both ends... also useful are double ended female connectors that can join those cables to make them longer... NOTE: the polarity in this video is in error. With piezo in this orientation, black wire should go to BNC center pin.

[@jenbry97]

@@theGADGETSplaylist Thanks. I've got my piezo sensor oriented so the white patch faces the open end/pressure source. I spent more time than I thought I'd have to and still didn't find anything conclusive about which way is up for that type sensor. It's only hot glue, so I can always reconfigure. Good tip on the double ended cables - no doubt they come in handy from time to time.

[@theGADGETSplaylist]

@@jenbry97 I would turn it around and have the brass facing the nipple. Piezo is under considerable stress under full manifold vacuum and if that "white patch" crumbles, pieces may get sucked into the engine... It's also easier to have wires point towards BNC ...

[@ozriblit]

Nice build, I’ll check for some close metric pipe sizes and build one. The scan time is 5 milliseconds per division, not 5 mega seconds. Lower case m is milli, upper case M is mega.

[@theGADGETSplaylist]

What is meant to be said and what comes out is sometimes 2 different things...lots on my plate in doing these videos... If you have access to a 3D printer, then the DS-PDS (GADGETS#132) is so much easier to build...

[@juanmgomezb]

Excellent... Very well explained. I'll do mine following your instructions Thanks

[@theGADGETSplaylist]

if you have access to a 3D printer (a friend, perhaps) GADGETS#132 is a much easier build Good luck with it, Juan:)

[@dennisryan2508]

I like this, also seen something like this to measure fuel injector pulse's, I think it was on Scannerdanner channel, he used a fuel pressure sensor from a gas tank.

[@theGADGETSplaylist]

Most of us follow the same guys. Paul is on top of his gave, as is Eric O and Yvan. Oscilloscopes have really come into their own and ingenious approaches are developed all the time. The sky's the limit. I appreciate you dropping by...

[@dennisryan2508]

made one of these few years ago to deteect injector clicking. www.flickr.com/photos/dennryan/6965039142/in/dateposted-public/

[@theGADGETSplaylist]

+Dennis Ryan - I checked it out. Holy screeching! Seems quite involved. I confess to not quite getting it. I watched KY Garage doing a couple of videos on what seems the same subject and didn't quite get it there either...so it's just me:) Thanks for sharing.

[@dennisryan2508]

Theres to much noise with the engine running, the tool picks up the sound waves (injectors clicking) a turns on the led light. I was using the drill to pickup everytime welding rod hit a bump in the drill tighter.It was a simple circuit to make and i got it from a project book that came with breadboard, after i made the circut i placed it in the gun, the gun was orignially a ele bug spray gun.

[@juanmgomezb]

Hi again... I have a question that comes across... Is the size of the piezo sensor important? I meant, the bigger in size you have, the better signal you get? And the internal diameter of the hose matters? Any size that you recommend?. Thanks for your reply. Good day

[@theGADGETSplaylist]

I too was curious about this until I featured #125 ROTKEE PDS Sensor which uses a smaller 27mm piezo than the 35mm used in my builds. Surprisingly, no difference.

[@juanmgomezb]

@@theGADGETSplaylist thank you. Good day! :)

[@alanw5879]

Would using a cap in the circuit anywhere have any effect, or resistors? I've seen so many different types of this build. Some use diodes to produce just positive voltage, but I know putting one of these on the intake, we want to read into vacuum. Same as in-cylinder. I used 1, 2" in. Disc and it produces almost 5 volts alone. Figuring out the custom probe for pico is the tough part. Measuring while testing the voltage swings are huge.

[@theGADGETSplaylist]

Pulse Transducers tend to be strictly piezo with RAW voltage and no custom probe setting... Again Alan I invite you to join our HScope group. I think you and the group would benefit:) t.me/hscope Denis

[@juanmgomezb]

Hi, may I know what brand is your tablet? Thanks

[@theGADGETSplaylist]

In this video it was a LENOVO TAB. In more current videos it is a LENOVO TAB4 (very nice but unfortunately discontinued). LENOVO followed up with the M10 also good, had the SNAPDRAGON CPU (you may still be able to find some of these on clearance...directly from LENOVO site...got 1 this week for my wife) The current LENOVO product line uses MediaTek CPU which I hesitate to recommend.

[@juanmgomezb]

Very kind... Thanks. Have a good day

[@jamesl197999]

What are the size of those piezoelectric discs you bought on eBay are they 35 mm. Thanks

[@theGADGETSplaylist]

+James L - yes, 35mm and do make sure you order them with the leads already soldered on... Good luck with project:-)

[@weldingjunkie]

Are you using 35mm sensors ? I might make my own just to see how I do.

[@theGADGETSplaylist]

Yes, 35mm piezo...here and in the latest 3D printed version in GADGETS#132 Check that one out if you or a friend have access to a 3D printer...does not come any easier than that one... Good luck with build:)

[@gcmd5852]

I can relate to the soldering the wire to the piezo, I ruined a few lol. Kinda have a handle on it now. That’s a nice 1 1/2” reducer with the 1/2” pipe thread you used on the front. Where did you get that reducer if you don’t mind me asking?

[@theGADGETSplaylist]

that was just off the shelf at my local building center plumbing dept... I also direct you to #121 at the 5 minute mark where I show a small white polyethylene flange that provides additional support for 35mm piezo...

[@gcmd5852]

@@theGADGETSplaylist Yes seen that. I’ve been using the 41 & 50 mm piezos. I’ve done 1 1/2 and 2” tube versions. Just experimenting with different ideas. You’d be surprised how close ( with some filtering) they all are (ranging from 27-50 mm).

[@theGADGETSplaylist]

@@gcmd5852 it's not just that the piezo diameters all surprisingly give similar response....that 1/2" hose on this build inserted in tailpipe produces "same" results as the 1/8" hole of the ROTKEE PDS sensor also in tailpipe...go figure

[@gcmd5852]

@@theGADGETSplaylist I’ve tried different inlet diameters also. The 35&41’s actually have larger piezo ceramic discs than the 50. The 50 just has the larger brass it sits on. Definitely interesting little pieces. All are pretty comparable ( smaller CI and simpler intake manifolds) unlit you hook them up to day a v8 with the larger intake manifold with all the different inside designs, them cause the sensors to kinda get crazy. I’ll have to try my hands at doing a video assembling one and maybe show my oddball experiments lol. That could be a don’t waste your time trying these pulse sensor ideas heading.

[@theGADGETSplaylist]

@@gcmd5852 you my friend sound like a good candidate for our HScope TELEGRAM Group. Why not check us out: t.me/hscope Denis

[@jeffgrizzel9499]

Great video. Excellent tool build. I’m looking forward to building one. Can you share the link for the sensors from China? I’m also looking forward to an in-cylinder transducer build if you get time. Great job and thanks again.

[@theGADGETSplaylist]

+ Jeff Grizzel - These are the piezo discs I ordered on eBay. You must choose "with flying leads" and select the 35mm size. www.ebay.ca/itm/281673370157 Good luck with your build:) There will be a kick-ass in-cylinder pressure transducer build video as soon as all the components get here from China 😎

[@forkliftgeek10]

Nice build sir. Appreciate the shout out. Where about in Canada are you from, if you dont mind me asking.

[@theGADGETSplaylist]

+ForkliftGeek - Kapuskasing, still enjoying winter🙂

[@forkliftgeek10]

logical canuck Lol. Company vans just got changed to summer tires then GTA got hit with snow yesterday.

[@bhartwigutube]

Too funny - I was going to ask the same thing, thinking maybe Upper Ottawa Valley, where I am originally from.

[@guussano]

By the way I did not find more old videos, I don't know what happens?

[@theGADGETSplaylist]

all the GADGETS playlist videos starting with #1 are still up...the channel was restructured a while ago into this single playlist...

[@guussano]

English and I would like if it were possible that I put signs in the videos thank you very much again God bless Canada

[@theGADGETSplaylist]

what kind of signs? do you mean subtitles?

[@guussano]

Logical canuk hi how are you? Thanks for answering, how I don't understand much English some words I don't know and I would like if it were possible that for the next videos you would put signs like arrows In what I'm pointing out for people like me, let's understand more thanks again

[@theGADGETSplaylist]

@@guussano Hay un pequeño "engranaje" en la parte inferior del video. Esta es la configuración y permite subtítulos. Pueden "traducir automáticamente" a muchos idiomas, incluido el español. Espero que esto ayude.

[@guussano]

@@theGADGETSplaylist muchas gracias por sus atenciones

[@guussano]

I'm thirty-two years old in this and I love learning, but I don't understand much

[@theGADGETSplaylist]

we learn one step at a time and eventually it all comes together...at least, that's the plan:)

[@guussano]

If someone is interested in a lover of mechanics and the English language look no further is my addiction