Thanks for the informative reply!
For another 30-11024 block signal I've never used I'm going to look for the timer with relay in option 2 as it seems a simple and cost effective solution. I have a 12V DC adapter that I will use as the power source.
For my existing block signal I have an old Radio Shack 275-206 relay (12V DC, 3 A, I believe 160 ohms) and a full wave bridge rectifier with the + of rectifier going to + coil of relay and - of rectifier going to - coil of relay. The signals do work correctly.
The problem is I get chatter if the wheels are even slightly dirty. I have a 1000 MFD 35V capacitor across the relay coil with - to -, + to + but I get no delay in signal changing and I get the chatter. I already had this setup in a previous layout several years ago and it worked fine, so I'm wondering why the chatter is there.
I also added 33 ohm 1 W resistor to the wire going to isolated track which I've seen in several threads for this arrangement to eliminate sparks on the wheels. Did not add a diode, but I have some available if needed.
