digi thermo
hi godwin,
as mention by k7elp you can try the LM34 for your temp. sensor. as an added info there are i believe 2 kinds of LM34, they are LM34CH in a TO-5 casing and LM34Z in a TO-92 casing. both are fahrenheit temp sensor. the LM35CH & LM35Z are centigrade sensors.
if the above items are not available there is another way of making a simple temp. sensor, that is if accuracy of temp. reading is not of utmost importance.
you can use the 2N2222A as your temp. probe configured to act like a diode. then feed the output to an op-amp like the 741, from the emitter connect it to the inverting input, from the base/collector connect to the non-inverting input thru a variable resistor. this variable resistor is used to adjust the output of the op-amp from 2 - 3v. connect your output to your DMM. whatever is your reading, multiply that by 100, you have your F* temp.
am sorry i cant post the schem, its lost somewhere, what am doing now is just look at my pcb. by the way am using this sensor to test the temp of a heatsink to check whether i have used the appropiate heatsink size.
hope this could help.
p.s. i almost forgot to mention, this device should have a 5v supply. if you are interested with this i could draw up the schem and post it here or thru email. :wink: