I want a pushbutton when pressed and released to trigger a 5 second (or x seconds whatever) voltage level change (high to low or low to high doesn't matter) without using a timer ic. Any guidelines? Thanks!
You could use a single MOSFET which has the advantage of a very high input impedance, allowing a larger value of resistance and a smaller value of capacitance then a BJT.
The circuit would be +V\(\rightarrow\)Start Key\(\rightarrow\)capacitor\(\rightarrow\)MOSFET gate & resistor with resistor\(\rightarrow\)ground. Connect the MOSFET source to ground and the drain through a resistor to +V (resistor value determined by load). This will cause the MOSFET drain output to go momentarily low and then back high when the Start Key is pressed. Try R = 10MΩ and C = 0.5μF to start.
To reset the capacitor you will need to add a resistor, 1MΩ or less, from the switch output to ground.
The relay will operate immediately the push switch is pressed, and stay operated until the capacitor discharges,time depends on coil resistance and capacitor value, bigger values = longer time delay.