3pcs PWM Low Voltage Motor Speed Controller DC 1.8V 3V 5V 6V 12V 2A 1803BK 1803B Adjustable Driver Switch with Speed Control Knob (Pack of 3)

I bought this because I am using a big "blower" style fan in my PC case but it's just a 12V unit with no tach or PWM wires, just positive and negative. My motherboard can turn it on and off about once per second, but at the full 12V it's super loud and honestly moves way more air than I will ever need. I hooked up the 12V feed to the input terminals of the board and the fan wires to the output terminals. Simple as that. The hardest part was figuring out where to put the board so the wires would reach and the knob would be accessible. If I had to make one complaint, it's that there's not many turns in the knob, so to get exactly the fine adjustment of the speed you want you have to have a steady hand on the knob. Now I can set the fan perfectly so it's exactly the right balance of speed and noise. Five stars!

I have an old 2-speed rechargeable Dremel tool made with four 1.2V Ni-MH cells (4.8V total) that would no longer hold a charge. I removed the mechanical 2-speed switch and replaced the Ni-MH cells with an externally mounted 3-cell (11.1V) Lithium battery and one of these little speed control boards. I used a piece of 3M VHB mounting tape to attach the battery to the case. I happened to have the battery and a suitable charger on hand. (A two-cell battery would have been more than adequate.) It's not pretty, but it holds a charge for a year or more and runs forever on a charge.

ITS IS GREAT AND WORK

I'm using them to control two small 12v motors and gearboxes in a toy I'm building for my grandson. Worked flawlessly. I really appreciate the connectors the manufacturer selected - the screw connectors were extra-easy to use compared to some of the other components I also used. Very well labeled too so absolutely no confusion or soldering is required. I highly recommend them and I'll use them on my next project too.

ok

easy to use; high functionality; value for the money...

Bought these to explain how solar works. It made everyone go “Ah”!

This is a basic low power pwm signal generator. For the most part, it works. The pwm signal is quite a mess, though, as you can see from the waveform from a scope in the photos. It should be a square wave with adjustable duty cycle. With all those harmonics, I am not surprised that I heard a fairly noticeable 13 kHz squeal using a couple of my 2 wire DC fans (yes, this isn't the ideal controller for those). But it did adjust the fan speed of every fan (pwm or dc) I tried. I've switched to a higher-quality pwm 4 pin controller available here at Amazon; search for 'B0BHNC776L' (without the quotes). But in fairness, from that seller, the price of the higher quality part was higher, so YMMV.