Homebrew PCBs

> David, You could try making one. The REPRAP group makes pid temperature
> controls for the heated bed and extruder.


Ok, I looked up the RepRap PID, and they use the 'usual chip' for the
thermocouple, the AD595.  Sparkfun - http://www.sparkfun.com/products/306 -
have them for $18.  The other 'usual chip' is the MAX6675, and it's $12.
Ouch.  You still need a display, controls, microcontroller, PID coding,
power supply and a few other bits & pieces.

I think I'll take my chances with the $25 eBay unit.

My only problem with that unit is it doesn't (I think) send a signal when it
reaches temperature, you could use that to start a timer.  It has an alarm,
but that's only for under/over-temperature.  I figure I can do it by
monitoring the heater, and when it switches off for the first time use that
to start the timer.

Oh, and I should mention it doesn't have a SSD built-in, but it can drive an
SSD.  It also has a relay that can handle 240v @ 3 amps.

Tony