The realization of my voltmeter Bluetooth need a reference voltages for testing. I suggest mounting around a PIC16F690, LCD display, adjustable by buttons and ADC (24 bits) and DAC circuit. The voltage would be 0 to 10V with an accuracy of 0.1% with 100mA and relay to connect or disconnect (reset button). What do you think?
21th Fevruary 2014
it's easy to increase the temperature. But against, with a fan, it is obtained that the ambient temperature. Is it really necessary to make a Peltier cooling system and therefore the cost?
3rd June 2014
The box begin to look fine