Free (Almost) MachTach Machine Tachometer

[EdK]

I have this tachometer tested and ready to go out to someone that can use it. All I ask for is the cost of shipping. I programmed in 10 slots or magnets for the testing. You can program it with your actual number. All the ranges tested worked from 2 - 97% duty cycle. I'm pretty sure it's edge triggered, interrupt driven.
The board draws about 60mA of current at 9VDC. Depending on the sensor you choose, the current required will go up. Power it with a 9VDC wall wart, or any other 9VDC source. Just make sure it's an electrically clean power supply. If you have problems with erratic readings you can add a filter choke in between the power supply and the tachometer. Some installations have been electrically noisy and needed the filter choke to stabilize the readings. This particular board is one of the older versions. It had a smaller surface mount 5VDC regulator which got too hot for comfort so I replaced it with one that's in a larger package, TO-220. I epoxied it down to stabilize it to the board. I ran a burn in test on it and the TO-220 barely got warm. The newer boards switched to the TO-220 package.

The connector is a TE Connectivity AMPMODU MTE series 6 pin connector. I can include the mating connector with 12" leads if you'd like.

The frequencies listed below are the PWM frequencies from the signal generator. at 5VDC output.

5Hz = 30RPM
10Hz = 60RPM
20Hz = 120RPM
100Hz = 600RPM
200Hz = 1200RPM
500Hz = 3000RPM
1000Hz = 6000RPM

Ed

P.S. I have two more boards that need to be assembled and tested. Then I will also be offering these for the cost of shipping.

         

[Hawkeye]

Now you've got me going, Ed. I have one on my bench that stopped working sometime after the fire. It lights up when powered. I just don't remember what the symptoms were. I'm already trying to troubleshoot the Arduino tach I made a few years ago. Might as well play with two at once. This one already has the TO-220 regulator bolted to the board. Ver. 2.3 6-25-11

[EdK]

(10-06-2023, 10:27 PM)Hawkeye Wrote: Now you've got me going, Ed. I have one on my bench that stopped working sometime after the fire. It lights up when powered. I just don't remember what the symptoms were. I'm already trying to troubleshoot the Arduino tach I made a few years ago. Might as well play with two at once. This one already has the TO-220 regulator bolted to the board. Ver. 2.3 6-25-11

Send it to me. I'll fix it for you, no charge.

Ed

[Hawkeye]

Thanks, Ed. I think I'll hold it in reserve for the winter - fill in some time between camping and snowshoeing.

[EdK]

Another one ready to go. I had to modify the board a bit because the encoder that this board uses is not available anymore so I had to use a different one that fit the footprint on the PCB.
This one is not as deep but it's obviously taller.

Ed

         

[Highpower]

I should have bought a second half size module unit back when Henry still had them available. That's what happens when you put things off for too long.

I've been nothing but happy with the one I put on my mill.

[EdK]

(10-29-2023, 07:24 PM)Highpower Wrote: I should have bought a second half size module unit back when Henry still had them available.

Post number one of this thread shows a half size module available for the cost of shipping.  

Ed

[Highpower]

I assumed that one was already spoken for since you've posted the second one now.

That being the case, you know where I am so send me what you need to have for it and I'll send it your way.  

[EdK]

(10-29-2023, 07:54 PM)Highpower Wrote:

I assumed that one was already spoken for since you've posted the second one now.

That being the case, you know where I am so send me what you need to have for it and I'll send it your way.  

Will do.

Ed