Thermal printers and (cheap) power supplies
Why does a thermal printer need a good power supply?
Because heating dots need a lot of power! With my cheap ‘5V – 2A’ wall transformer, here is what happens to the supply voltage when I print a picture.
My thermal printer draws a lot of current, and as you can see, the voltage can drop as low as 3.7V! It’s clearly not enough to print a beautiful, deep black:
Next mission: buying a better power supply. (Like I said in my previous post, reducing the number of heated dots is a workaround.)