Homebrew PCBs

"Stefan Trethan" <stefan_trethan@...> writes:
> Or you could simply use a thermistor, pot, transistor, and solid state
> relay, throw that together and be done with it. If you think about it,
> there really is no need for rocket science here.

What's the working range for thermistors?

I was thinking of using a MAX6675 chip, which goes from type K to SPI
readout of degrees directly, with no extra math or hardware needed.
An R8C MCU with an ADC pin reads the pot, and the LCD displays the set
point and the roller temp in actual degrees (rather than just 0..10 :)

I figure for $50 in parts (including power supply module) it lets me
know it's set to the right temperature, something I see only in
laminators costing hundreds of dollars.  My thought is that I can set
the desired temperature to a specific setting according to the specs
of whatever I'm laminating, and know when it's at that temperature.

> I know you like to play with software so it probably doesn't pain
> you as much as me.

There is that :-)