In Reply to: Re: circuit help wanted posted by John Flint on 09/25/03 at 9:11 AM:
OK. Since the coil is 200ohms, the 3055 only needs to drain 60mA or so. The 3055 may be overkill but it will work.
Check out Fairchild's data sheet for the 6n139. The hookup will be like Fig 2 or Fig 3 depending on how you hook up the transistor. (ignore the output gate)
Relay coil+ to 12V
Relay coil- to 2n3055 collector
2n3055 emitter to 12V return
2n3055 base to pin 5 or pin 6
If you use pin 6 tie pin 5 to 12V return.
Use about 150ohm for R2 and 1K should be ok for R1.
Let me know how it goes. And ... just wondering ... are there no electrical engineers there at Dawson that you can talk to?