Adjustable resistor / indicator
- DISCLAIMER: I DO ELECTRONICS AND 3D DESIGN SOLELY AS A HOBBY. THERE COULD BE ERRORS THAT CAN RESULT IN ALL KINDS OF DAMAGE. USE THESE DESIGNS AT YOUR OWN RISK.
- This design is released under Creative Commons Zero (CC0) license.
- See also:
2 Project description
I needed a way to experimentally find resistance that works best in certain circuits. Usual potentiometers could not handle required power dissipation and were not precise enough.
Solution is to build adjustable resistor:
Logically there is series of resistors that increase in resistance in the power of 2: 0.5, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512. Each resistor can be enabled or disabled by a switch. This makes entire range of 0 – 1023.5 ohms available with the 0.5 ohms precision.
Here is front panel for switches:
Sometimes I would like to use lightbulbs with various parameters as test load/indicator. Current device has 4 of them included.
Here is front panel for light bulbs:
After assembly using prototype PCB:
Following body is used as a case and PCB support:
Cover on the back:
Download: STL file