hi.im a mechanical engg student to start with....
id like to know how i can go about filtering and then comparing a voltage signal from a thermocouple...using a cheap, easily available devices.
i want to actuate solenoids frm this signal...do i really want a microcontroller for it....?

 

Ad595 + Lm311 + Bjt

 

The AD595 is indeed a handy chip. No need for the LM311, as the AD595 has an on-board comparator. (See figure 9 of the datasheet.) A BJT may or may not be able to drive the solenoid, depending on specs. A Darlington pair or a MOSFET with driver should work nicely.

Adis, can you share the specs on your thermocouple and solenoid? Also, what are your temperatures of interest?