I purchased this relay on a pcb board and it has a place for a diode, transistor, resistor and a led. These are surface mount except for the diode. I have a bunch of in4001 diodes and I put that on. How do I determine what i need for a transistor and a resistor?
Have you done due diligence in researching the PCB? If there are more of them around, you might find clues on the internet. Look on Ebay for example. Try and track down a schematic. If you can't, the circuit is likely very simple so you can trace it visually and with an ohm meter. Then use generally accepted design principles to choose a transistor and resistor.
I found what I needed.