At roughly $20 to build, this 9 digit pulse counter is an excellent example of home built tools. The builder, [Josh] found himself repairing a device and in need of a pulse counter. With the components cheaply available, he just built his own. He says that it has a few limitations, like display brightness, but overall it seems to do the job well. You can download the PCB from his site.
[via MakeZine]
Simply Sweet. Try putting some shades to the display, maybe negative photo film.
or drive the led correctly
anyway good tool
I second using shades on the display, it’ll help a lot!
yes, but it does it’s job, he acknowledges the flaws, and has solutions if he were to do it again. So congrats to him. I like it
A few octal line drivers would up the IC component count but might actually be cheaper than discrete transistors. Feed the enable line with a variable freq clock and you can dim the display.
Maybe I’m not seeing the “hack” here, but most counting ICs have an overflow which can cascade the count into another IC…
@Erik,
if you want a hack take a $2.00 calculator and a couple components and make a 9 digit counter on the cheap.done that back in the 70’s with a high end HP cal.Basically using a transistor to pulse the + and 1 keys.
even easier with most cheap calculators if you enter 1 , press = then add 1 then press the = button again it increments the count so you can wire just the = button
Pedometers can be found at most Dollar stores.
substitute the pendulum switch for the input pulse,
and you have a real cheap counter with an LCD display. But it will probably be limited to 1ppsor so.
Oops!
I meant 1 pps (pulse per second) or so!
Homeland Security will be at your door shortly.