Veglia Tachometer digital conversion

...the tach in my car has something like that, before I got obsessed with this myself I sent the tach to PA speedometer to 'just have them restored' and it came back with a board hot-glued in like this...

The Dino circuit is simple (as are other '555 tach circuits), the surprising thing is that (with the billions of Veglia tachs) that the beautiful circuit board isn't immediately available on Ebay...Even, not a universal board. But I suppose one reason is that most people aren't going to have a function generator around to set the input frequency and calibrate needle/trim pot.... But making the circuit itself with a universal PCB could be simple...

  The original Veglia circuit is not complicated either, just a couple transistors--but for me trying to test it (here in my Townhouse in Taiwan....) the issue was getting the 'trigger' to work--and trying to build an inductive amplifier (to take the frequency generator) should have been simple but failed me. So instead I took the Stepper Motor challenge. https://pantera.infopop.cc/top...93#19905352128593293

But another idea is to buy a cheap 2" 8krpm universal tach, make sure its triggering--then gut it and use the PCB or even the whole movement. Or (assuming the question is just the trigger), try that tach amplifier for $30...Lee

(oh, and in case the idea of transplanting a whole movement into the Veglia can is interesting, 2 things; (1) re-use the Veglia plastic bracket. (2) be patient beyond patient in fitting the Veglia needle onto the replacement shaft...the replacement motor is almost certainly bigger diameter, which then means either micro-surgery to drill out the female end on the needle and if break the 1mm or so drill bit into the needle, the only donor is another DeT gauge...)

Jon Haas (Pantera Electronics) has his own tach repair technique that is effective and less expensive than other repair methods.

Here is another solution that I used to correct the Tachometer readings on my TVR.  It was reading double the actual RPM after a Pertronix module was fitted…

https://spiyda.com/smiths-rvi-...onversion-board.html

...Mike, I'm guessing that your problem is just that you need to adjust the Tach to the "V10" mode...probably just a tweak of the trim pot. You could try this on your Fiat piece and avoid one step under the dash...

   Here is a schem taken from the reliable internet for the Veglia, it is simple. the only place that things go 'wrong' when mixed up on the ignition source is the filtering section there the south-west quadrant. Otherwise, the Q1 transistor pulses vaguely with every spark and pulls a current thru the meter, with a final gain set by the trim pot (R10). I think its possible that All veglia car tachs (no matter 4,6 or 9  cylinder) just twist the trim pot.

  The Dinoplex circuit is simpler than it looks, the part internally has its own schmitt trigger to clean up the noise and react to the edge (not just the 'weight' of the spark, as the Veglia) and send a single pulse. (and something I'd be likely to do, the pin names on the CD14538 are a bit messed up...and come on, man, CMOS inputs should never be left floating... . But yup, its about $8 worth of parts....Lee

My take on these diagrams...

https://youtu.be/Ac7G7xOG2Ag

MH

...that is so awesome, I have new hero in a "take my word for it..." engineering role model. And clearly filmed a long time ago, because now $750 million would not be considered expensive, esp for the government..."

https://en.wikipedia.org/wiki/Turbo_encabulator

  And Mike, that is the beauty of trim pots...when I was in college, other guys were making measurements of their sacred transistors, drawing load lines, whatever and I would just grab a potentiometer and tune it till it worked.  Maybe I have Italian blood somewhere there...

@leea so you're saying that even if i build the turboencabulator, I will still need to trim it's pots...?   Ok, if I'm trimming pots I'll start with the Fiat tach and get a feel for it...  Then try the REAL tach if i get foolishly overconfident...  (seems inevitable).

Updates will follow...

MH

Well, I just have to add this but in doing due diligence, i.e., research, it is difficult for me to believe that a Pantera owner would never have heard of Pantera Electronics?

P-E is in fact Jon Haas. One of the many Pantera specialty products that he has made is a plug in ignition controller that unlike the MSD (might suddenly die) is 100% reliable, is a plug and play AND get this, works with the Veglia tach.

Now considering some of the issues that get posted here on this forum, I am not entirely shocked that he goes undiscovered by some. I just don't get this situation where people can find this forum after crawling out from under their rocks but not P-E?

That really is unfortunate but somewhat troubling to me. I envision some owners as have "obtained" their Panteras because they really wanted a pickup truck and thought that the rear decklid kind of resembled one and just traded "Bossie" their milk cow for it?

Strange. Very strange.

@panteradoug I've never found insulting the intelligence of potential customers to be the most effective form of promotion...  But that is just based on my own experience.

I would also imagine that many of the people in a "Tech" forum are here because they want to know how something works and enjoy building and repairing things themselves, as opposed to the complex procedures involved with clicking "add to cart" .

While not all Pantera components are shared with the Mangusta (this was posted in the Mangusta section BTW), many are...   and hopefully PE can be of help to those that have reached an impasse...

Here is a link for those that are interested:

https://www.pantera-electronic...ectricalproducts.htm

MH

Oh, I've bought stuff from Pantera Electronics before, and traded mails with Jon just to chat...And he reminds me of the kind of engineer I always dreamed to be--Lee

Insulting? Hum? A rose by any name would smell as sweet.

When the car won't start and the solution is just that they didn't know they had to turn the key, and this repeats and repeats and repeats, I tend to side with the Ford perspective (and to me that is shocking because I normally call them out) that there was no market for a car that did not conform to the expected results.

It may simply have to do with the relatively radical thought of the car to begin with for it's time? It is shockingly different then a Camaro or even a Mustang of the time.

It is also a result of obtaining a "Horse of a Different Color" at the absolute bottom of it's value?

But I can't help but wonder how some owners wound up with the car and how so many have such little insight in to it? How they can immediately come to the conclusion that an MSD is the proverbial solution to all without an iota of even a Google search for options?

I openly admit that I'm no genius. Not the brightest star in the night sky, but the vision of putting the body on the frame of a four wheel drive Toyota and running the Baja is just so ridiculous that it turns my gut sour.

How someone comes here essentially yelling rape because the car won't start and not know the battery ground needs to be connected?

I don't think that a Pantera was something to start with for a first car. Perhaps one of those kiddie pedal cars is more appropriate?

OK, maybe it's just me and perhaps I should feel flattered that they come here even if they didn't know where to put the gas in the tank? But sometimes I just loose the patience that others expect and not realize that it too is a gift, a talent to be able to hold ones cool to have to explain what A, B, C's are when it should be how to solve a simple quadratic equation and I just don't have that talent?

I suppose it is just a peeve of mine and I should apologize  to those attempting to crawl out of the turnip fields and find the light? Yes, that should count for some Brownie Points.

Doug -

You should own of those British cars, where all they do is take their vehicle to high-end restorers, and give them 80,000 Quids, and then get it back two years later.

Only a few of those dudes ever work on their own cars.

You could have a field day with them! At least our original poster was able to get his car fixed, even after he asked some questions. Good for him.

Everybody’s gotta start, their journey to enlightenment somewhere!

Rocky

...Doug, I think your point is aimed to someone other than us? Rocky, you cannot believe how far 80k quid -doesn't- go on a car restoration, at least in the world my brother lives where 3000 hours is the minimum spend. And his story is like I think just about everybody on this forum, starting as a teenager with a Craftsman wrench and hammering on a rusty Corvair in a borrowed garage. Mike's point is that the learning and doing is inseparable from this hobby of ours.  And what a blast it is, a barrel of monkeys, even when we all clearly have a much more affordable path to just pay for a solution...Lee