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Questions tagged [tachometer]

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1answer
67 views

Automotive tachometer signal interpretation

I'm trying to build a custom dashboard for a car (Daewoo Lanos 1998 with Delco ECU). Tachometer signal, that comes to dashboard with a separate wire looks a bit strange to me. It seems that the signal ...
1
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2answers
145 views

Op-amp (LM358N) half-wave rectifier and 3.3V clamp

I was wondering if I could have some feedback on this circuit. The goal is to: Input up to 18VAC sine waves (possibly noisy) up to 20khz. Output 3.3V digital pulses. Minimize discrete part count. I ...
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1answer
67 views

Converting DC Motor's Tachometer Output to DC Using Bridge Rectifier

I have a DC motor that its specification states that "Electric DC motor manufactured by Buehler. Sinusoidal Encoder Output: 11.5 VAC - 870 Hz @ 12 VDC input. No load speed: 6800 RPM. Runs in either ...
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2answers
268 views

Tachometer Signal Voltage Reduction

I am working on a formula style car and creating a digital dash based on an Arduino. I currently have a signal from the ECU running at 12v DC and a varied frequency depending on the RPM of the engine. ...
1
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2answers
261 views

Dimming LED based on 12v signal

I've got an LM358 comparator turning on an LED. What I'd like to add is a way to dim the LED by a fixed amound when a 12v signal is sensed. It's in a tach circuit in a car, and when the headlights ...
2
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1answer
173 views

Spark plug pick up

This is a reformulated question to make it shorter. I would like to build a tachometer for an old moped. Since my moped has a magneto and points for ignition I must obtain the signal directly from ...
1
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0answers
295 views

Component identification from vintage tachometer

For the purpose of understanding how it works, I'm attempting to reverse-engineer the schematic of an analog gauge. For some context, it's an analog tachometer from the 70s, with a scale from 400 to ...
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2answers
2k views

Tachometer vs. Tachogenerator

Could you explain to me the differences between a tachometer and a tachogenerator? For example, is a tachometer just a tachogenerator attached to a dial to display RPM rather than voltage or are they ...
1
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1answer
451 views

12v PWM Fan Seems to Be Running Inversely of What It Should Be

I have a 120mm 12v Fan that is used on an Antminer S7. There are two fans on the antminer, and they both are controlled by the software built in. I had one fan break, so I replaced the fan with a ...
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2answers
363 views

Understanding an Ignition Circuit

I found the below schematic here to while trying to build a tachometer for my motorcycle. What does the circuit element labeled "BOARD" mean (directly left of the 22pF capacitor) - is it just a wire ...
0
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1answer
173 views

Electronic tachometer over reads

The electronic analog tachometer on my small boat diesel has recently started to overread on startup of the engine (e.g. it reads 2000 rpm on idle). After about 5 - 10 minutes it drops back quite ...
1
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1answer
1k views

How to read signal from Crankshaft Postition Sensor in motorcycle

I am trying to build digital tachometer for my motorcycle Yamaha FZS600 Fazer 2002. I have a problem with reading signal from CPS sensor. It is hall effect sensor, I suppose. I found the plug of it. ...
2
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2answers
314 views

12 Vdc Intel fan tachometer output to 24 Vdc PLC input

I'm working on a cooling fan rotation supervision system, and I'm planning to use my old 4-wire Intel E18764 12 Vdc cooling fan to test it (as I don't have access to the 24 Vdc actual fan I'm going to ...
1
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2answers
2k views

Motorcycle RPM counter

My plan is to make RPM counter to my motorcycle. I'm planing to read ignition box signal with arduino. I think that ignition box gives 0-12V (or 14.5V max) square wave signal to coil. I was wondering ...
1
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4answers
5k views

Finding RPM of DC motor

How can we find the RPM of DC motor using the given voltage?. To be clear, I need to find out rpm of a motor using the pwm signal sent from Arduino Uno. In my case i'm using a BO motor, the link is ...
0
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1answer
461 views

Reading ECU tacho signal with PIC MCU - noise issues

Am trying to read the frequency of a 0-12V square signal generated by a motorbike ECU with a PIC. Range 20Hz-300Hz I'm getting strange intermittent noise on the output of my optoisolator, and wondered ...
0
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2answers
791 views

How do I convert voltage square wave signal to 4-20mA signal

At school we are looking for a sensor that is able to count/sense the rpm that the shaft is turning at. I have found a sensor which does this but it sends out a voltage square wave: Datasheet I need ...
1
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1answer
939 views

Photodiode — photoconductive (reverse bias) vs photovoltaic (zero-bias) for tachometer

I'm building a tachometer for speeds 0 to 3600 rpm (various speed motors turning things down to whirligigs blown by the kids.). I've got a photo diode running in photovoltaic mode generating about 50 ...
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3answers
2k views

How do contact type tachometers work? [closed]

In case of contact type tachometers we put the tip into a small hole in the rotating body. Sometimes there is a disc in the tachometer shaft that we touch with the surface of the rotating body. What ...
1
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2answers
708 views

Diodes in Tachometer Circuit

How are the diodes helping in the attached ckt :-
5
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1answer
1k views

Converting a tachometer signal into something a microprocessor can understand

I am attempting to build a digital dashboard for my car (a 1998 honda civic), I have run into a bit of trouble, wherein the tachometer signal is quite hairy. I was wondering if someone would lend me a ...
3
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1answer
2k views

Read out tachometer from PC fan when manually turning the blades ( driven shaft )

I have a problem. I can read out the tachometer of a PC fan and convert it to frequency with just using a simple microcontroller and labview. Does anybody here have an idea how to read out the ...
2
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2answers
837 views

LED tachometer with PIC MCU (requires more current)

I've been working on an LED tachometer that will be installed on an open wheel race car. After putting the order through for the PCB I re-calculated the current draw and turns out the PIC's (16F877A) ...
2
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2answers
1k views

Inductor ground, where to put it

So I'm building a tachometer for my car. It's pretty simple, basically I have a wire wrapped around the spark plug wire about 10 times, and the 30-50k volts travelling through the spark plug wire ...
1
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1answer
708 views

How do i build a laser based tachometer?

I want to build a tachometer that has to be somewhere around 1 meter from the rotating shaft. I'm still to build a prototybe based on IR diode and phototransistor, but I'm afraid, I would get too ...