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JoeSBP

JoeSBP

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Gentlemen,

Needing some help and advice on a little wiring project. Below are the gauges i have decided to go with for my '69 Signet.

vbpgimage.php


These gauges are designed so that you can run either red or white LED back lighting.

vbpgimage.php


As you can see, you wire them up to power the white LED or red LED as you choose, simple.

vbpgimage.php


My idea is to build a harness for the tach so that it is normally back lit by the white LED, but at a certain RPM, power cuts out to the white LED, and the red LED is energized. Basically creating a shift light thats impossible to ignore. I know this can be done, but I'm just an old 11Bravo, so don't know where to start.
Even if there is some type of complete off the shelf module available to accomplish this, I would rather build it myself for the satisfaction and entertainment.

All legitimate responses and smart a$$ comments welcome

thanks in advance
 
Well the easy way I would think is to obtain a tach or other device with an RPM shift light and adapt that

Have you tried hooking up BOTH white and red to see what it looks like. If that is acceptable, you could then simply use the shift light to trigger the red

If you want to shut off the white, that would be a bit more complicated

One way to do that simply would be to use a little relay triggered by the tach light.

Frankly, you might "suggest" to the company that they build that in!!
 
67Dart273 said:
Well the easy way I would think is to obtain a tach or other device with an RPM shift light and adapt that

Have you tried hooking up BOTH white and red to see what it looks like. If that is acceptable, you could then simply use the shift light to trigger the red

If you want to shut off the white, that would be a bit more complicated

One way to do that simply would be to use a little relay triggered by the tach light.

Frankly, you might "suggest" to the company that they build that in!!
Click to expand...



I think that is an excellent idea.
A shift light would read the RPMs and trigger the red LEDs, and go off again under that RPM and automatically switch back to white.
Might be able to swap the inputs to the red and white LEDs in the lighting circuit inside the switching system. (depending on how it's done)

Oh Lord, it sounds like something I would try. :D
Great idea for them to change at a certain RPM.


Oh yea, I almost forgot the smart a** comment: Don't you have anything better to do?

Hows that? :D
 
Two of these would do it. Wire one to provide white led ground up to desired rpm then it would remove ground and wire the second one to have open ground for red until that same rpm is reached where the white goes out, this would provide ground for the red. Never tried it but seems like it should work. Kind of pricey but:dontknow::dontknow::dontknow:


http://m.summitracing.com/parts/sum-830449-1


Instructions
[ame="http://static.summitracing.com/global/images/instructions/sum-830449-1%20.pdf"]Access Denied[/ame]
 
You could users switch dubob found with a relay that has both normally open and closed contacts. Switch would activate the relay white would be hooked to the normally closed tap and red to the normally open. White would be on until rpm is hit and the. Turn off with the red light coming on
 
I like the vintage look of your choice of guages and engine turned panel.
Clever shift light idea also.
 
I do similar using my ECU and graphical display on PC and Android devices. I measure RPM, by measuring the time between cylinder events, for fast update and internal use in fuel and spark delivery. The graphical user interface, GUI displays RPM as a greem bar, turning to red, and also show numeric value. I do that on temperatures and boost indicators too. The GUI is the part there the RPM set points are adjusted, however the ECU has built in RPM limiter. The RPM limiter cuts off fuel as necessary to regulate RPM. It is very smooth, but can be heard. The GUI reports many more real time parameters, AFR, TPS throttle position, intake temperature, engine temperature, injector pulse width, ignition timing, MAP, ECU temperature .... But what I enjoy most is driving, hearing the engine sing, forgetting all the gauges.

After the excessive post above, to do the light change, use a micro controller. If you do not have a conditioned RPM signal (0-5V pulses), then that needs to be done first. My ECU puts out a tach signal, since direct fire systems have multiple coils. The tach out connects to tach, and does not load the ignition like a normal tach does on a coil. Then write a program to measure and compare to settings you desire, and control pins to drive mosfets for driving LED. The Arduino nano board can be purchased for under $10, and can be programmed via a USB connection to a PC. While this may sound difficult, it is not.
 
toplscuda said:
You could users switch dubob found with a relay that has both normally open and closed contacts. Switch would activate the relay white would be hooked to the normally closed tap and red to the normally open. White would be on until rpm is hit and the. Turn off with the red light coming on
Click to expand...

This is something I considered also, and could very well do the trick.



KitCarlson said:
I do similar using my ECU and graphical display on PC and Android devices. I measure RPM, by measuring the time between cylinder events, for fast update and internal use in fuel and spark delivery. The graphical user interface, GUI displays RPM as a greem bar, turning to red, and also show numeric value. I do that on temperatures and boost indicators too. The GUI is the part there the RPM set points are adjusted, however the ECU has built in RPM limiter. The RPM limiter cuts off fuel as necessary to regulate RPM. It is very smooth, but can be heard. The GUI reports many more real time parameters, AFR, TPS throttle position, intake temperature, engine temperature, injector pulse width, ignition timing, MAP, ECU temperature .... But what I enjoy most is driving, hearing the engine sing, forgetting all the gauges.

After the excessive post above, to do the light change, use a micro controller. If you do not have a conditioned RPM signal (0-5V pulses), then that needs to be done first. My ECU puts out a tach signal, since direct fire systems have multiple coils. The tach out connects to tach, and does not load the ignition like a normal tach does on a coil. Then write a program to measure and compare to settings you desire, and control pins to drive mosfets for driving LED. The Arduino nano board can be purchased for under $10, and can be programmed via a USB connection to a PC. While this may sound difficult, it is not.
Click to expand...

Kit, although your solution would be one of the electronic ways to do it I think we are trying to figure out a way that most anyone could do it without a degree in electrical engineering. :D (he did ask for "electronic guru's though, didn't he?)

I have been interested in the Arduino capabilities myself, but just started looking into it recently.
Some of it is pretty interesting, but hard to figure out exactly what it can be used for.
It's kind of like having the internet and not realizing a lot of the things we can do with it.
One idea pops up and leads to another, and then another and on and on. :D
 
Trailbeast,
Arduino for me is cheap hardware, it has the micro and support stuff assembled, for less than I can buy parts. I do not use the Arduino development software. I use CodeVisionAVR and write directly in C. It is a trivial project, in my world someone could ask for it a 10:00 AM, I could get it done and go for early lunch.

Here is how it is done. Start with a tach signal that is conditioned for the input capability of the micro. An internal timer, is set up to trigger on an edge of the tach signal. There is a feature called an interrupt, when the edge happens, the code associated for using the timer gets run. The timer has adjustable clock rates based on a crystal oscillator. The timer is constatly counting up, reaching a maximum, and starts at zero .... It is what is called a free running timer. The time between edges is 1/4 revolution of engine for a V8. The reciprocal of time is frequency, RPM is frequency. The time is measured by taking the present timer count, minus the prior count. Each count is based on the clock rate that was set. So just simple grade school math. Subtraction, division, multiplication, yes the micro does that. With that said, if you are not displaying RPM, put the compare point directly, and just use raw difference of period. No division, or multiplying required by micro.

The next even easier part is the compare, "if (rpm >= SHIFTRPM)" a couple code lines control LEDs in the desired way, or the following "else" controls for normal LED condition. The >= is greater than or equal to.

So excluding the start code that initializes the micro, put there automatically by the compiler, the code written for the indicator is just several lines, at most. There are even setup wizards for timer and pin settings.

There may be a learning curve the first time. It may take a bit, to figure out methods, like how to incorprate features of the micro. That often involves using timers to measure time, output signals, read inputs, measure voltage, or communicate with other devices. Sometimes it takes a few parts, but often much can be done with a few resistors, capacitors, diodes, and transistors. Small part like those cost pennies.
 
KitCarlson said:
Trailbeast,
Arduino for me is cheap hardware, it has the micro and support stuff assembled, for less than I can buy parts. I do not use the Arduino development software. I use CodeVisionAVR and write directly in C. It is a trivial project, in my world someone could ask for it a 10:00 AM, I could get it done and go for early lunch.

Here is how it is done. Start with a tach signal that is conditioned for the input capability of the micro. An internal timer, is set up to trigger on an edge of the tach signal. There is a feature called an interrupt, when the edge happens, the code associated for using the timer gets run. The timer has adjustable clock rates based on a crystal oscillator. The timer is constatly counting up, reaching a maximum, and starts at zero .... It is what is called a free running timer. The time between edges is 1/4 revolution of engine for a V8. The reciprocal of time is frequency, RPM is frequency. The time is measured by taking the present timer count, minus the prior count. Each count is based on the clock rate that was set. So just simple grade school math. Subtraction, division, multiplication, yes the micro does that. With that said, if you are not displaying RPM, put the compare point directly, and just use raw difference of period. No division, or multiplying required by micro.

The next even easier part is the compare, "if (rpm >= SHIFTRPM)" a couple code lines control LEDs in the desired way, or the following "else" controls for normal LED condition. The >= is greater than or equal to.

So excluding the start code that initializes the micro, put there automatically by the compiler, the code written for the indicator is just several lines, at most. There are even setup wizards for timer and pin settings.

There may be a learning curve the first time. It may take a bit, to figure out methods, like how to incorprate features of the micro. That often involves using timers to measure time, output signals, read inputs, measure voltage, or communicate with other devices. Sometimes it takes a few parts, but often much can be done with a few resistors, capacitors, diodes, and transistors. Small part like those cost pennies.
Click to expand...

Thanks for the very clear explanation (that helps) :)

All these cool things we can do with electronics but so little time and brain space left at the end of the day.
I'll still check into it more as time allows.
I assume (hope) there is an online or downloadable list of command lines for that software, right?

Thanks Kit.
 
Right now, I am actually working on an example to show how to use an arduino nano as a distributor signal simulator, and a RPM based trigger unit, using a second nano. A nano has an on-board LED, that will be turned on, when the RPM reaches and exceeds set point. I will make a new thread in this forum.
 
Yeah. And you are comfortable with programming LOL. For us old guys, "this is hard"
 
Like most things, learn by doing. I started by programming HP calculators in the early 70's. The manuals had good examples. Start there, make changes, see what happens.

I got ignition simulator and shift point indicator working. The shift indicator also displays RPM via serial port, so it can be used to calibrate tachs. I need to document and add comments. That is more difficult, than the few lines of code.

This forum does not have code tags, so the formatting of code will be messed up. Project files are not readable, so not sure a post here will be good to use. I may have to post a link to a technical site called AVR FREAKS, for the micro I use.
 
KitCarlson said:
Like most things, learn by doing. I started by programming HP calculators in the early 70's. The manuals had good examples. Start there, make changes, see what happens.

I got ignition simulator and shift point indicator working. The shift indicator also displays RPM via serial port, so it can be used to calibrate tachs. I need to document and add comments. That is more difficult, than the few lines of code.

This forum does not have code tags, so the formatting of code will be messed up. Project files are not readable, so not sure a post here will be good to use. I may have to post a link to a technical site called AVR FREAKS, for the micro I use.
Click to expand...

If it's avrfreaks.net I found it.
 
I decided to do ahead and post here the best I could. Many of the AVR freaks guys are much better programmers than I, exposing my code there could be a disaster :).

Here is my post http://www.forabodiesonly.com/mopar/showthread.php?t=326021

TailBeast,
You know there are some hints in all this, for you to make electronic advance control for the GM HEI....

The period between ignition cycles on a V8, is 1/4 revolution is 90 degrees. The period measurement gives you timer counts, subdivide that for timing control. That is the basis for my ignition control, except my timing sensor is more usable, it gives me an edge for max and minimum timing. That puts the target in the desired range, increasing accuracy.
 
There's a lesson here for you "youngsters." Don't be like this old man "a hardware freek" do yourself a favor and learn some programming.

Arduino, Rasberry pi, "Basic" and "C"
 
Life is too short for me, I am skipping Raspberry pi, went directly to Android, and use B4X.

If you learn any programming language, the rest are similar enough you can wing it. Do not worry about learning it all before starting, learn as you go. Most start by turning an LED on and off, then build from there.
 
KitCarlson said:
TailBeast,
You know there are some hints in all this, for you to make electronic advance control for the GM HEI....
Click to expand...

That and possibly a rev limiter. :D
I was thinking this days ago.

Thank you very much for putting the time into this.
 
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