Ive searched high and low looking for an answer to which resistor to use. I know it is the 10K-Ohm resistor, but is it the 1/4 watt or the 1/2 watt resistor? Thanks for your time.

 

According to Voltage = Current * Resistance, assuming 12 volts and 10k ohms, your current through the resistor will be 1.2mA. Wattage is Voltage * Current, so 12*.0012 gives you 0.014 watts that will be dissipated through the resistor. That's 5.6% of the 1/4 watt resistors maximum power dissipation. So go with either one really, but the 1/4 will be fine.

Sorry to get all technical on you... I was studying for my Physics 2 exam when I ventured over here.

Oh and I haven't done the tach mod yet, but make sure you know whether you're wiring it in series or in parallel...it matters quite a bit!

 

well there is a write up that tells you where to solder it. And i've used 1/2 and 1/4, both work fine.

 

https://www.yotatech.com/forums/f160...l#post51339142

 

The 1/4w maybe a better fit. I think its a tad smaller than the 1/2.

 

How about 1/8 watt?

I'm starting to get really frustrated with how difficult it is to find something so simple and common..

Have a whole bag of 1/8 watt resistors and I'd really like to get the tach working!

 

1/8 = 0.125

0.125 > 0.014

You should be fine

 

Yeah, figured that after I posted.. its only about 11% of the total capacity.

So for anyone wondering it doesn't matter if its 1/8, 1/4 or 1/2 watt.