If it’s cheap & compact, it’s not user friendly.
If it’s compact & user friendly, it’s expensive.
If its high quality, it’s expensive and huge.
And all I need is compact and relatively cheap resistor decade for my projects.
I don’t need 5W metrology grade elephant to see what series resistor is needed for LED not to burn my eyes.
By some chance I stumbled upon a project from “tardate” on GitHub:
https://github.com/tardate/LittleArduinoProjects/tree/master/Electronics101/DecadeProgrammableResistor
The idea of thumbwheel switches from Aliexpress and set of resistors was excellent, with some modifications of course.
Ordered parts (from Aliexpress):
Thumbwheel switches 22x8mm Black, Decimal Code Output (10pcs)= 8,35€
1206 SMD resistors 1%: 1, 10, 100, 1k, 10k, 100k (100pcs of every value) = 5,5€
ABS Plastic enclosure: 65x50x55mm = 3,3€
Banana sockets, 4mm which I already had in my stock
Total cost = 17,5€
I’ve cut out the hole for switches, and installed the banana sockets with 19mm distance for the compatibility.
Out of 100 resistors from each value I’ve selected 10 closest to desired value.
Resistors were then soldered and everything assembled.
Resistor decade described in article is max. 999 kOhm, 1/4W.
I will also build another decade in slightly bigger box which will contain 7 thumbwheel switches for range up to 9,9 MOhm with 1210, 1/2W resistors .
