Question! and Help I need to build a v8 engine servo motor governor

[Soeren]

Hi Neil,

Actually if you watch close the last VR1 turn in the video and look at the servo and VR1 turn closely I am at full turn, way before the servo's movement ends if 2 seconds is way before . Actually I can count it's time here as being around 2 seconds until it stops.

OK.

Actually the servo pulse high time swings from ~1.7mS - 2.2mS. You can see the Servo High Pulse slow as it is reaching it's minimum high time.

Is there a close correlation between TP4 and the servo pulse (measured with both traces of the 'scope)?
And how does TP5 look at either extreme (900/1500)?

It almost gives me the impression that a CAP is discharging down slowly through a resistor making the action described in the last 2 seconds I hope you can understand what I am describing?

Would reducing the value of C6or R9 change servo's pulse to bottom out faster? "Just trying to learn"

That sounds highly unlikely.

[wheelyneil]

Hello Soeren

Please excuse me if I pronounced your name incorrectly on the Video's

Okay here we go, hope the video's help as I am having a hard time explaining what is happening with my limited know how and I know when I am explaining things I confuse you because I do not know all correct terms I am sorry :'(

Checking of TP4
I was very surprised to see the servo act correctly after I attached the scope probe to TP4. When I did this the servo moved a little and I had to turn VR1 of SCHEMATIC1 almost to 0 ohms, Then the servo swing started to act normal and had no delays when going back and forth between 900 -1500. So like I the said in the video I hope that it helps Identify the problem

Checking of TP5
Now I hooked the scope probe to TP5 and tried to sweep the TEST GEN, the servo was trapped in a small swing movement less than 90 degrees I adjusted VR1 schematic1 to just below half it's range and the the servo would give me 0-135 movement again. BUTthe delay was once again present as before. IF you watch the 2nd video very close you can see the slow section of the pulse width.

Please make sure your glasses are on

Glasses are a good thing, as I have learned from this project because wrong componets keep showing up in the circuit, I don't know how it happens I try to keep it at a minimum of 10 or 20 at a time :P

It appears that the scope is having some kind of effect on the circuit at both TP's

Well have a look at the vid's Maybe you will see the clue you need
[youtube=640,505]http://www.youtube.com/watch?v=cYqDlLeuviU[/youtube]
[youtube=640,505]http://www.youtube.com/watch?v=Xfh4mShlmCw[/youtube]

[Soeren]

Hi Neil,


A quick and short post before sleeping:
The videos made me see what I should have previously, at least when you asked about R9/C6.
C6 doesn't have a discharge path all the way, so when you added the scope (~1MOhm), it was able to discharge further.
If you try adding a resistor of 1MOhm (or around 2MOhm to lessen the load) in parallel with C6, I think you'll have the delay cured - the exact potentials at TP4 can be raised by lowering the value of R9 somewhat if needed.

I'll review the videos tomorrow to see if I can discover something else.

[wheelyneil]

Good day Mr. Soeren

Well I made the change by adding a 1MEG ohm resistor in Parallel with C6, which fixed the delay

But the servo was trapped again and would not hardly move by adjusting the VR1. I tried decreasing R9 but no improvement so I put the 470k back in the circuit.  So I was looking at the completed schematic and in your last change you had increased C7 to 68n so I tried increasing it to 100n and the circuit started to act correctly, I hope this action won't damage the circuit.

I now have VR1 on schematic1 set to a little under 50k  about half it's max and when the Gen Test is set to 1200RPM the VR1 on that Circuit is also centered . So Everything is ~mid- range and I have no delay from 900 - 1500
Below is the JPG of the Changes.

So did I  do any harm by adding the 100n  cap Hope not I shut it off just encase

I'll check in the morning as I am heading to sleep now.

[Soeren]

Hi Neil,

Well I made the change by adding a 1MEG ohm resistor in Parallel with C6, which fixed the delay

But the servo was trapped again and would not hardly move by adjusting the VR1.

Now I'm a bit curious as to how you knew that the 1M fixed it then?   

I tried decreasing R9 but no improvement so I put the 470k back in the circuit.  So I was looking at the completed schematic and in your last change you had increased C7 to 68n so I tried increasing it to 100n and the circuit started to act correctly, I hope this action won't damage the circuit.

Great initiative.
Increasing the cap makes it take longer to reach a certain voltage, so it matches better the lower voltage at TP4 caused by the resistive divider of 470k and 1M.
Changing one comparator input means you have to change the other proportionally, to get the same effect.

I now have VR1 on schematic1 set to a little under 50k  about half it's max and when the Gen Test is set to 1200RPM the VR1 on that Circuit is also centered . So Everything is ~mid- range and I have no delay from 900 - 1500
Below is the JPG of the Changes.

I'll update and post in a few minutes.

So did I  do any harm by adding the 100n  cap Hope not I shut it off just encase

Not at all, as described above.

Was that the last changes? Or, in other words, is is working as intended now?

[Soeren]

Hi Neil,

Here is the modified schematic

[wheelyneil]

Hello Soeren

Thanks for the updated Schematic

Now I'm a bit curious as to how you knew that the 1M fixed it then?

Actually after placing the 1meg in, I powered the circuit up. As soon as the power came on the servo moved from 0 to 135 degrees with no hesitation, so I assumed the delay was fixed Then trying to swing the RPM's w/VR1 the servo would barely move.

Increasing the cap makes it take longer to reach a certain voltage, so it matches better the lower voltage at TP4 caused by the resistive divider of 470k and 1M.
Changing one comparator input means you have to change the other proportionally, to get the same effect.

Thank you for that info, as it helps me to understand why the circuit corrected after raising the cap value.

Or, in other words, it is working as intended now?

Correct! Now were having fun

I will mount the Vero Boards to a hard surface over the next day or so.
So I have a good stable platform while working around the Engine. I wish it would warm up so I can go out and play coldest winter in 35 years here in Florida

Any other info I should know before attempting this testing of the " SOEREN 1200 dISCRETE COMPONET GOVERNOR"?

"The SOEREN 1200" kinda has a nice ring to it

OH yes almost forgot to ask, what value in-line fuse should I use when hooking it to the engine voltage supply?

[Soeren]

Hi Neil,

Actually after placing the 1meg in, I powered the circuit up. As soon as the power came on the servo moved from 0 to 135 degrees with no hesitation, so I assumed the delay was fixed Then trying to swing the RPM's w/VR1 the servo would barely move.

Ah, I see.

Correct! Now were having fun

Didn't we before? 

I will mount the Vero Boards to a hard surface over the next day or so.
So I have a good stable platform while working around the Engine. I wish it would warm up so I can go out and play coldest winter in 35 years here in Florida :'(

Oh, life is hard:

To put things in perspective: Temperatures in DK
My GF lives in Copenhagen (the upper pic), I live in Kongens Lyngby (and the last one is where our summer cabin is).
So excuse me for not taking you all too serious here

Any other info I should know before attempting this testing of the " SOEREN 1200 dISCRETE COMPONET GOVERNOR"?

"The SOEREN 1200" kinda has a nice ring to it

Sounds like a sixties commercial for Snake Oil
Besides, you have been pulling hair and working hard for "2 years", so let's rather call it "The Neil V8 9-10"  (As seen on YouTube - end of infomercial).

OH yes almost forgot to ask, what value in-line fuse should I use when hooking it to the engine voltage supply?

Not quite sure what your servo takes, but I'd think 1A (make it a Slo-Blo to counter start surges from the servo motor) should be appropriate.

I have been playing around some with the PCB, but it's a bit of a puzzle to get it nice and proper, so I won't get it finished today.

[Soeren]

Hi Neil,

Please take a look at this and tell me if you think you're up for it. It's a bit crowded, but if that's a problem, I could make it into two smaller PCB's to stack.

[wheelyneil]

Hi Soeren

Hey that is great  I think I will have a go at this size first as I like it being compact.

I am mounting the vero's today and maybe test the circuit the beginning next week my "GF" is requesting my full attention this weekend you know how that happens

I will be updating, as progress is made, or problems arise

OH YES!!! anything below 21c is just to cold for me.......BRRRRRRRR Actually this is a good weekend to be inside where  I am located it will be high's 12c with rain mixed kind of just miserable.
I am way north of Miami, we don't always enjoy those trade wind breezes up from the Caribbean
HECK I DONT EVEN KNOW HOW TO SPELL  -- Care a bee an!

Tak for lån Soeren

[wheelyneil]

Hello Soeren

Just a quick question, is using all 1/4 or 1/8 watt resistors okay to use on the PCB? I dont beleive it was ever mentioned that high watt resistors were needed

Just asking to help with space

[Soeren]

Hi Neil,

Just a quick question, is using all 1/4 or 1/8 watt resistors okay to use on the PCB? I dont beleive it was ever mentioned that high watt resistors were needed

Most can be 1/16W if needs be.
Assuming 14V max over any resistor (most will have far less), the formula is: U^2/P = 14^2 / 1/16 = 16*14^2 = 3,136 Ohm.
Meaning that any resistor of at least 3k136 can be 1/16W
The limit for 1/8W would thus be 8*14^2 = 1k569
And 1/4W is 4*14^2 = 784 Ohm

R6, might seem to be a candidate for 1/4W, but 1/8W will be quite sufficient, as it won't see 14V for more than the first few ignition pulses at start up.

R11 sees only a small voltage from IC3, so no problem in using 1/8W or 1/16W there.

R22 should be 1/4W.

[wheelyneil]

Hi Soeren

Thanks for the info on the R's

Below is a picture of boards mounted and ready for testing. I have to do some linkage work, but it wont be long now and VROOM, VROOM , VROOM

[Soeren]

Hi Neil,

Below is a picture of boards mounted and ready for testing.

You have way too much Vero board 

[...] it wont be long now and VROOM, VROOM , VROOM

Oh, you think there's still a lot of jitter?
I hope it'll be more like VROOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO... 

[wheelyneil]

Hi Soeren

You have way too much Vero board!

Do you Think I should cut it down 1 or 2 mm to make it look just right  

I think I will put the PICF675P chip Gov onthe last 50mm of the Vero and run the head to head against each other

I hope it'll be more like VROOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

A steady 1200 would be VRPERFECT!

Hey I just bought a pickit2 and am learning how program with it. I am working a circuit that uses a pic12f683 and I already have the firmware so it will be good to learn the hardware side with it.

Any ways I was going to ask you if after I get a little more know how on that Pickit2 and get the NEIL V8-9-10 on the PCB if I could squeeez that little bit of code out of you that was suggested  for that PICF675P chip Gov. Now that I took the hard way and actually built the discrete set up, I feel better about trying the easier road with the PIC on later projects.

Thought I would run that past you, not that I haven't been Squeeeeeeeezing for the last 4 and 1/2 months

[Soeren]

Hi Neil,

Do you Think I should cut it down 1 or 2 mm to make it look just right  

Haha, no, I was merely thinking on how expensive Vero Board is in DK (which is why i went to lengths to cram everything together in my youth - and still is by habit ).

Besides, the larger the PCB, the more support it needs to avoid a premature death, especially if mounted on an engine.
The classic mounting with a hole in each corner is particularly bad, partly because people thing it's then completely supported and partly because it really ain't - observing a PCB on a "vibrating table" (I lack the proper English term) is very informative in how good support is done (you should allways make your support in "triangles" if your PCB can be bend down in the middle, as they're rigid, while "squares" are bad on anything over a certain size, depending on the thickness of the carrier material).
The smaller/the thicker the PCB, the more rigid it is of course.

I think I will put the PICF675P chip Gov onthe last 50mm of the Vero and run the head to head against each other

Great!

Hey I just bought a pickit2 and am learning how program with it. I am working a circuit that uses a pic12f683 and I already have the firmware so it will be good to learn the hardware side with it.

Any ways I was going to ask you if after I get a little more know how on that Pickit2 and get the NEIL V8-9-10 on the PCB if I could squeeez that little bit of code out of you that was suggested  for that PICF675P chip Gov. Now that I took the hard way and actually built the discrete set up, I feel better about trying the easier road with the PIC on later projects.

I just saw that you were asking about the '683.
Now do you have '683 chips, '675s or don't you have any yet?

I can change the circuit to a '683 in no time (I allready added the ICSP connector and have moved the used pins to avoid clashes) and whether I compile for one controller or the other is just a matter of selecting it from a drop-down list.

[wheelyneil]

Hi Soeren

I just saw that you were asking about the '683.
Now do you have '683 chips, '675s or don't you have any yet?

No not yet I am ordering tomorrow and so I will get them ~Wensday. The other circuit I am starting calls for the 683
A buddy of mine ask me to build it for a swimming pool area to put behind a watterfall w/ some High power RBG led's. I thought it would be good to learn using the Pickit2 and my test boards, bread, proto, practice, ECT............. wish they would standardize this issue

Any ways here is a link to it.http://picprojects.org.uk/projects/bigmosfetrgb/ This what I'm up to, making toys for Christmas HO HO HO

[Soeren]

Hi Neil,

No not yet I am ordering tomorrow and so I will get them ~Wensday. The other circuit I am starting calls for the 683

There's also this on the download page:
"V2 HEX file ready to program for 12F629/675"

Any ways here is a link to it.http://picprojects.org.uk/projects/bigmosfetrgb/ This what I'm up to, making toys for Christmas HO HO HO

At least for starters, I'd recommend using just one of the 8 pin PICs and perhaps a larger one like 16F628 for when the smaller ones just haven't got enough I/O.
Better learn one type reasonable well before spreading out, to avoid the possible confusions over their dissimilarities in the initial phase.

Whichever you go for, please tell me, so I can make it for the same type.

[wheelyneil]

Hi Soren

I ordered the 675's today so if you want to work it up that's the chip I am going to learn with
I also grabbed the Hex file today, so it's in my program folder.

Thanks for letting me know I didn't see that!

[wheelyneil]

I got all the componets ordered today, and bought a old laser printer to make my transfers.
 
I printed out a couple copies of the V8 Gov and I had to get the 1:1 factor set, after that it came out great. I put a 4093 on it and the pins were right on the money.

I didn't have any Photo sensitive board yet, so I am going to try the Iron on method w/ glossy paper and see what results I can get.
 
I ordered a few of the 16f628A'S today also as I think you are right that maybe I should learn on a chip that has a little more to give then the 12f's
Just have to wait for the stuff to get here!

[Daanii]

Having kept an eye on this thread since the beginning, I'm glad to see the governor getting close to completion. Soren's hardware solution looks like a good one -- simple and powerful.

Using a microcontroller as an alternative for part of the circuit makes sense too. The PICs work for that. But I like the Arduino and the AVR line of chips. You may want to take a look at those. Very easy to program yet powerful enough for projects.

[Soeren]

Hi Neil,

I printed out a couple copies of the V8 Gov and I had to get the 1:1 factor set, after that it came out great. I put a 4093 on it and the pins were right on the money.

Then this PCB should be a piece of cake to do 

I didn't have any Photo sensitive board yet, so I am going to try the Iron on method w/ glossy paper and see what results I can get.

The PIC circuit shouldn't be a problem for that method and If you go with that, there's no real reason to make a PCB for the discrete build.

 

I ordered a few of the 16f628A'S today also as I think you are right that maybe I should learn on a chip that has a little more to give then the 12f's

If you need X-tal timing accuracy and a couple of inputs and outputs, the more pins on the '628 quickly comes into play.

Just have to wait for the stuff to get here!

Ah, the joy of expecting - Before you know, that baby has grown all mature and you probably forget to talk him/her on a daily basis 

[Soeren]

Hi Daanii,

You may want to take a look at those. Very easy to program yet powerful enough for projects.

I think that you'll agree, that learning one core at a time is the best way, especially for a first time intro?

The PICs are just as easy to program (and code, if that's what you meant) as AVR and other cores based on the ancient 8080. Each time you meet a new core, you have to read up a bit, but if you get the underlying principles and are familiar with the differences of the Harvard and the von Neumann architectures (probably a lack of this is what is feeding much of the AVR ctr. PIC debate), as well as the main principles of interfacing, you can pick up the new stuff pretty quickly. That is, if you developed a sound understanding of the logic way of thinking the first time 'round.

I hope we can avoid the "religious" debates over which hammer is best on a 3" nail - you don't see carpenters argue over oak, fir, hickory etc. as they're all materials which all carpenters should know and be able to work with, although they probably each have their favourites (mine are pokkenholz and ebony, but I'm not a carpenter, so I don't have to care about the price tag ).
When the nail is buried deep in the piece of wood it holds in place, who cares what hammer drove them.

In short.., It's just nail 'em and forget 'em 

[Daanii]

Your point is well taken. I retract my suggestion.

[wheelyneil]

Hello Soren
Well made my first attempt at making a PCB with the Laser print to Iron on process

I learned a lot as to how clean it has to be and soak time to allow the paper to release.

For a first attempt I was happy and to get most of the circuit complete it was great, a couple more tries and I think I'll have a pretty good Idea of what it takes to make it right

I think the pre- sensitized boards would be nice to have. I'm going to order some shortly.

I don't know what size a couple of those spots between the trace lines were, but let just say a needle had a hard time getting in between to clean stuff up  "TIGHT"

I almost got the ID stamp to come out it was small

Well more fun tomorrow, after some sleep.

[wheelyneil]

HI Soren
Got all my goodies today Pickit2 and all the componets, just like Christmas all excited and couldn't sleep!

I got the first 675 programmed w/ the RGB HEX file using the pickit2 it was pretty easy , now just have to build the circuit and give it a try  

I am working on a couple more attempts at getting that PIC Gov Board finished and no lift marks would be nice

I am going to drill out the circuit below I think it will work fine for the job at hand

Hope that issue with the 675 timing isn't being a Hugh pain while making the code

And I don't care what everybody says about you! Your still okay by me.  

"REALLY ALWAYS LOTS OF THANKS TO YOU FROM HERE"

Talk at you later!

[wheelyneil]

Hey Soren

I am needing your opinion. When drilling PCB's w/ say w/a dremel tool  are HSS or Carbide bits a better choice to use.

I have a feeling that breaking a few is possible @ 1.2mm

[Soeren]

Hi Neil,

Nice job with the PCBs (although the first one is the nicest IMO).
When you do toner transfer, set it to "very black" (without overdoing it of course) and do touch up with a Sharpie or similar etch resistant pen - and a scalpel or similar can be used to scrape off toner in places where there should be none.
Pieces of broken hacksaw blades is really useable for making scrapers to break connections between traces, whether before or after etching.

I am needing your opinion. When drilling PCB's w/ say w/a dremel tool  are HSS or Carbide bits a better choice to use.

I have a feeling that breaking a few is possible @ 1.2mm

If you have a drill stand, carbides are best, as they cut clean holes, while the HSS variety will be dulled pretty fast and start drawing the copper upwards in a little volcano shaped dimple.
Perhaps an HSS will last an entire board when using phenolic board, I shy from that, as glass fibre board is "impossible" to crack, but it does kill HSS drills.

But... If handheld, only use HSS or you will break them faster than dulling a HSS as the wolfram has no give. Don't trash carbides when broken, but save them for scribes. Mounted in a piece of tube (i make a hex-crimp on a copper tube), they just need a short trip to a grinder and you have a perfect scribe that marks any metal.

1.2mm is OK for the larger holes, but 0.8mm gives a more solid fit for ICs, resistors and caps - the components shouldn't be carried in solder, but drawn sideways, cut and soldered and it's the bend that should lock the component in place. The solder is just for electrical conductance.

Btw. If you need to redrill a hole to a larger dimension in a partly populated board, don't use carbide - much to easy to kill them that way.


I'm still trying to figure the best solution for the program, but have been busy on family matters - Still on it every second I get to be online.
 

[wheelyneil]

Hi Soren

I'm still trying to figure the best solution for the program, but have been busy on family matters - Still on it every second I get to be online.

  You have givin up a lot of your time for me on this so,No rush here!     

And yes the first PCB was a lot cleaner, I will drill both and use as needed. I have learned a lot and yes there is a great need for some extra tools to clean the jobs up also.

If by chance there is a different PIC, that would make things easier to write for, let me know and I'll order anyone that's needed if it makes it any easier on your end and I can still program it with the Pickit2.

I know this project is running a long time and I am sure you wouldn't' mind it getting wrapped up

Night Soren

[Soeren]

Hi Neil,

And yes the first PCB was a lot cleaner, I will drill both and use as needed. I have learned a lot and yes there is a great need for some extra tools to clean the jobs up also.

The missing pad can be replaced with a wire formed into an eyelet and soldered onto component and trace. That shouldn't detract from stability if done carefully.

As I mentioned, hacksaw blades can be used for a variety of scrapers. I have a range of odd shapes for this and that, all made similar to this:

This was made from a 10mm acrylic rod and about 5cm of a hacksaw blade (the type with cobalt and wolfram in the steel). Araldite was used to bind it in a hole with "jagged" walls (made with a small ball shaped router in a "Dremel") and the blade was serrated along the edges as well to bind the glue better.
A cutting wheel was used for the rough shaping and a wet grinder for the edge.
Every now and then I hone it on an oil stone (finishing off on a well oiled slab of Hard Arkansas) and then it's razor sharp.
I mistreat it a lot, since it's easy to get it back in shape and this particular one (the only one of them I have here at my GFs place), have seen around 20 years of bashing, which explains the color tone of the Araldite.

If by chance there is a different PIC, that would make things easier to write for, let me know and I'll order anyone that's needed if it makes it any easier on your end and I can still program it with the Pickit2.

I'm about to have a solution I think - found some code snippets that I have to toss around and add to, to keep both timing requirements in check.
Another way to do it would be to use two controllers to get mint timing and let one control the other, but that's bottoming out I think - I think I'll have something for test in a couple of days (Oh, there's a birthday party tomorrow, but anyway).

One thing that you could do, to familiarize yourself with the stuff and to prepare...
Controllers like the '675 that is made to be able to run from an internal RC oscillator is individually calibrated in manufacture. The calibration data is embedded in the code space at the top addresses and must not be overwritten (or you'd have to recalibrate it yourself).
If you take the ones you got, mark them in some way (like 1, 2, 3 etc. don't know how many you ordered) and read the entire code space and save as a file for each (number them in a way that you can differentiate them, the calibration data will be different from one to the next).

Whether this is necessary or not, depends on the programmer and whether it will write the entire space, but it's not a bad idea to have saved the data - just in case.

I know this project is running a long time and I am sure you wouldn't' mind it getting wrapped up

It's not that it bores me or nothing, but I think it should be mounted on that warm lump of shaky metal for a cosy time soon

Btw. Have you considered how you wanna box it in?