Hi,
Not sure why im stuck with somthing so simple as this, but i really cant work out what's wrong - <phew> i have admitted defeat! :?
Looking at the picture attached, the transistor is driven from a PIC ( 0V or 5V o/p ).
When R1 is driven with 5V, the transistor *should* turn on, and in turn, switch on the relay.
The relay is a 12V / 400R (30mA) type, and is functional - so is the transistor.
I have checked the relay by shorting out C -> E on the transistor, it switches as expected.
The transistor has been checked in a DMM, and tested OK.
When the PIC drives the Base, the voltages in the transistor are as follows:
B: 5.1V
C: 12.32V
E: 4.5V
Not sure why the emitter is so low...
Help !