Could someone please help a newbie design a small transistor circuit to drive a relay (wiring, value of resistors, direction of diode across coil)
I have a 2N5089 transistor
I have 2 relays that I want to drive (separate projects):
- Relay #1 is a NTE R74-11D1-5 (5V, 178ohm coil, 140mw)
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- Relay #2 is an NTE R12-14D5-6 (6V, 160ohm coil, .9w)
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What do you suggest for power supplies? Could I use the PC power supply
5v/12v for the circuit or am I better off with an independent supply?
In both projects I want to tap into an indicator LED on a separate circuit for on/off condition of relay.
If you could give me a rule of thumb for calculating resistor values for different relays I would appreciate it.
TIA