Build your own VR conditioner
 

<p>The quick and dirty version (just how yall like it)</p><p>I'm personally using this for ABS sensors and traction control with megasquirt.</p><p>Steps:</p><p>1. Read this shit</p><p>2. Get the gerber files from this&nbsp;link</p><p>3. Go to OSHPark and get 3 boards made for $5 (share with your friends, you probably only need one board)</p><p>4. Order a bunch of this shit (I ordered 2 extra of everything in case I fuck up soldering it all)</p><p><a href="http://imgur.com/tBSx4rZ" target="_blank"><img alt="" src="https://www.miataturbo.net/attachment.php?attachmentid=146714&amp;dateline=14 39356067" /></a></p><p>5. Learn to surface mount solder.</p><p>6....?</p><p>7. Profit?!?!</p><p>I'll be updating this as I build them. I'll also attach the spreadsheet tomorrow when I get back to my work computer.</p>

cool.

this is something I always wanted to add to my car but never got around to it.

The MAX9926 is probably the best VR decoder ASIC on the market today. Good choice.

Thats what my research has led me to believe. I think you said something along the lines if the noise rejection defies physics?

<p>Parts list with Digi-key part numbers.</p>

I had 3 of those chips built onto DIP conversion boards by some company in canada for pretty cheap for a different project. I think it came out to like $20 per + shipping. Mainly because I really really didnt feel like dealing with a surface mount chip on a protoboard.

<p>Details?</p>

Indeed we use the MAX9926 in our ME221 ECUs - good for VR or even hall if the other side is left floating :)

Proto Advantage - QSOP-16 to DIP-16 SMT Adapter (0.635 mm / 25 mil pitch)

chose pins and IC assembled from up top, and put in the digikey part number of the chip you want and presto it'll be at your door in like 2 weeks.

<p>Thats fucking awesome. Thanks.</p>

I've purchased their adapter boards in the bast (though I did my own assembly, because I'm a bad-ass with a soldering iron.) Good-quality parts at an excellent price.

Surface-mount isn't hard to do IF you have the right tools and are experienced with general soldering work. A Radio-Shack iron isn't the right tool. In fact, my fancy Weller is just barely adequate even with the expensive tip in it. When I worked at Harris, I took all my surface-mount work into the lab and used the $500 Metcal iron and the Bousch & Lomb stereomicroscope.

Moral: you can do it yourself if you try. But if you can pay someone else $6 to do it for you with the right tools, go that route.

<p>Had some fun learning how to surface mount solder</p><p>Attachment 232943<br />Attachment 232944<br />Attachment 232945<br />Attachment 232946<br />Attachment 232947</p><p>And here it is working</p><p> </p>

Just to be sure, this is just sine to square, right? No front/rear comparison, something that could be fed to a dinosaur ms2 as "knock."

<p>just 2 channels of sine to square.</p><p>Buy an ms3 buddy :) Do you already have a 3.0 board?</p>

What is a 3.0 board? Will a Ms3 daughterboard thing work in place of my ms2 microsquirt?

I need to buy a ms3 and sell this diypnp, should have done ms3 from the start...

<p>Nope. If its a diypnp then no.</p><p>Do it. Keep an eye out on ebay and classifieds here. turbofan got his for like 350.</p>

I've been soldering daily/weekly for the last 7 years or so. I stil dont want to attempt a componet like that.

Do it deezums. I have one more of these boards.

So many other things need money spent on them...

I still need a rollbar, and new tires.

Who wants to buy my diypnp, lol

<p></p><p>Told you I'd beat you in a fight.</p><p>I probably wouldn't try it without the microscope. It makes things 10000x easier.</p>

if you're putting this on an MS you know someone sells an even more convenient board that the one I posted earlier

The jbperf board?

It's honestly pretty easy, provided that you have very thin solder, a bottle of liquid flux, a high-quality iron with a good tip, and a decent microscope.

I've never tried it without all of the above, but I expect you could probably forego the expensive stereomicroscope with a decent watchmakers's loupe or head-mounted magnifier.

But, in all seriousness, surface-mount parts gets an undeservedly bad rap from people who are needlessly intimidated by them. Yes, you need different tools from those used for through-hole parts, but the skills are basically identical. You just use less solder and thinner tips.

<br />
<br />I wouldn't do it without one. Too easy to solder bridge IC pins.

I use the ST7 tip and .030" solder as it is...

That's probably why SMC seems scary. Pick up some .015 solder (eg: Kester 8806 / 9703, depending on your flux preference) and whatever the smallest tip Weller makes is. I honestly can't remember exactly which tip I used to use- it was a Metcal iron we had at work. Very convenient for this sort of thing, as the tips were quick-change. You just yank one out with pliers, shove a new one in, and it's up to temp and ready to go in about 5 seconds. I miss that iron.

I can solder a MAX9926 or a microMAX package without a microscope or a magnifying glass. 1%.

Aidan,

Can you explain why your parts list resistor values differ from the schematic?
You list a 1k resistor, but provide the digikey P/N for a 100k resistor?

It looks like you are only working with the Crank/Cam Hall or VR portion of the circuit; if i were to assemble this, I'd ignore the MAX9939 chip and that whole portion of the board?
https://svn.code.sf.net/p/rusefi/cod.../Schematic.pdf

No idea. I copy pasted this from the svn. It worked though. Wonder if I screwed it up. It works though.

Yeah. I'm only running the VR half.

Thanks.

Do you know the pin pitch and spacing on the 10 and 4 pin headers?

Normal? It matches everything I've ever used.

I'm just waiting on my parts now and trying to find a good soldering iron to buy. After looking at the Racelogic TC boxes and the variable %slip controllers they have, I got to wondering if this were possible with the MS3.

It seems like it is possible, given that there is an option under Advanced Engine -> Traction Control External %slip Input. This setting shows a chart where you can enable a 0-5V input and adjust the %slip allowed based on the knob voltage %. I looked around and ended up settling on a 6 position, dual pole rotary switch so I can put 1k resistors between each position on the switch.

That way, I'll have 0V, 1V, 2V, 3V, 4V, 5V (in theory anyway). I will then be able to hopefully set the knob positions to OFF(100% slip), WET (0% slip), 5%, 10%, 15%, 20%. Just like the Racelogic manual adjuster instead of the super fancy digital adjuster that has nearly infinite control. I chose the 2 pole switch so I can also have an LED indicator lamp for the knob position/mode.

The real magic in the race logic is using the wheel speed sensors to figure out how much you're turning and allowing variable slip based on turning. But it gets really pissed off of you lift a wheel because they're lazy.

That's badass. What switch? I want one for launch control too.

I would assume that if I use the wheel speed sensors I have already, but use them on the same side of the car (i.e. both on drivers side or both on passenger side). I have a higher probability of this MS3 traction control playing along nicely. And yes, Racelogic is magic, but this is $100 to try to get this right vs $900 for the racelogic system.

Am I wrong to assume that when turning left or turning right, both of the inside wheels will slow the same amount?

http://api.ning.com/files/p5DfxSv2mk...ackGuidev1.pdf
This guide gave me the basics and the idea for the LEDs and how to do the fixed voltage steps. I hope it works, I used to know some electrical things, now I don't remember shit.

He uses this switch for mode switching. MD00L1NCQD C&K Components | CKC7012-ND | DigiKey

I'm using this rotary pot for lunch control.
P16NM103KAB15 Vishay / Sfernice | Mouser
Kind of expensive, but it was a aluminum knob and looks good.

I want to use the rotary switch for launch control too so I have known values.

I just got all of my components in from digikey to build this board. Fuck me, those surface mount resistors and caps are tiny.

Get a microscope

Seriously, I hand solder 0402s without a microscope.

I just lay them on the board and then will the solder into place with my mind. Chuck Norris is jealous of my mad SMC skillz.

I believe that. But the pins on the max922X are fucking small. Way smaller than the 0402.

just tape it in place. scotch.

For those, I did use the good microscope at work. It's not so much the size as the pitch- there's not much space between the pins.

0402 isn't bad. I have super shakey hands so placing them sucks, but the soldering isn't bad. But mother fucker those pins are small on the max.

I can solder tiny chips with no hands.

I just put it in my toaster oven and snack on solder paste as I wait, that stuff is tasty on ice. Fuck RoHS, they take my trans fat they ain't taking my paste.

I don't have any experience with surface mount components and pretty limited experience with soldering. I do a lot of clusterfucky stuff with wiring, not so much with circuit boards and 0 with SMCs. I learned to do some through hole components at a summer camp when I was 12 and in college. I've got 3 chances to get it right, hopefully one sticks.

I thought that at least the NB sensors already generate a square wave. Never checked though. Not sure if it's 12V or 5V. In any case, just running it through a double inverter should get a nice square 5V signal. I'm not even sure why we go through all the signal conditioning trouble with the MS, other than the signal conditioning circuits are already there when following the assembly instructions, so we may as well use them.

Somebody who actually scoped the signals and understands what the MS conditioning circuitry does, please correct me!

And on the soldering:
I'm too old and have bad eyes, shaky hands and all that good stuff. Trying to hand-solder 0402 components is totally frustrating under those conditions.
So for SMD I usually get a stencil from oshstencils. Spread some paste, add components under a $25 Ebay microscope, bake it in the old toaster-oven for a few minutes and Bob's your uncle.

Did someone say scope?

https://www.miataturbo.net/attachmen...ine=1448654301

Not sure what sensor your referring to. Both the ABS and Speed sensors output a VR sensor sine wave.

Doh!
I was referring to the CAM and CRANK sensors. Didn't even consider ABS and Speed.
Never had any issues with my speed sensor though. Seems to be reading accurately and reliably. My '99 doesn't have ABS, so that's pointless to check.

This is for driving an NB cluster when you don't have a speed sender. Or using ABS as speed inputs into the MS.

Now this whole thread finally makes sense to me!

Glad to see some rusEfi stuff here :)

:bigtu: Thanks for your stuff russian. I'm kinda interested in doing a rusEfi build. Next miata I build will probably attempt to run on one :)

Man, all this talk about soldering under a microscope... My hands shake so much I've always been proud of how decent I could solder regular sized things lol.

Get off the crack. It stops the hand shaking.

My hands only shake when I get off the ethanol.