I work as a "mr fixit" in a university research lab. I'm more of a problem solver, arguably an electronics novice, definitely not an EE.
I've been asked to update the design of a vintage solenoid driver circuit that uses an SK4935-98209 opto-isolator and a 2N3053 NPN transistor to take a TTL input and drive a 24 VDC solenoid. I've found that the NTE3044 opto-isolator and NTE128 transistor work fine, but these NTE items are marketed as replacements for out-of-date parts, and I wonder if there is a way to use more contemporary parts, and any VALUE in using newer parts if replacements are still available.
I've been asked to update the design of a vintage solenoid driver circuit that uses an SK4935-98209 opto-isolator and a 2N3053 NPN transistor to take a TTL input and drive a 24 VDC solenoid. I've found that the NTE3044 opto-isolator and NTE128 transistor work fine, but these NTE items are marketed as replacements for out-of-date parts, and I wonder if there is a way to use more contemporary parts, and any VALUE in using newer parts if replacements are still available.