that's sad
I remember seeing radio shack's packaging during the early day of this thread.
yeah... the shipping cost is ridiculous for small qty electronic components.
but if I'm looking for a TLC, I'd go for something like mouser as well
oh...
I should mention this earlier,
we can determined the required current for the signal by measuring the resistance between PWM line and ground line on the fan.
my 9SG shows around 2.7k Ohm (I use a crappy meter, though).
calculate this value with Ohm's law: I=V/R (5/2.7k)
I get 0.00185A or 1.85 mA
and if I parallel two of this fans together, I'll get 1.35k Ohm of resistance between the PWM line and the ground
so both fan will roughly need 3.7 mA
your fan resistance value may differ, but you'll got the idea to decide which circuit to be used.
if your current requirement came close to the source /sinking capability of the chip (I'll take 10mA as the lowest value stated on the datasheet), then it'd be a good idea to use the dual TLC556 circuit.
as for the NE556, it can do up to 200mA (but always spare some headrooms)
I don't remember precisely on what page, but I can still remember Bobnova build this controller for Miahallen (pardon me if I write you guys' name incorrectly
) to control a wall of fans... was it nine or more
.... it's more than a bunch for sure.
the vid was super epic
I also spotted the issue for the circuit selection on page5, post #88.
pics are gone, but the vids are still there
edit: some vids are gone as well @.@
yep...
the 2-98% is super simple to build.
keep us updated with your project