Night/Day Sensor help

I play tekkit, and since my quarry can't operate at day because it runs off of solar power, I have a splitter cable to allow some saved energy to go to the quarry if i flick a switch. However, I want to use a computer to turn it on manually at night. I tested with Lamps, but two problems occur. Either the lamp will turn on and not turn off, or the program will stop with the message: "Too long with out yielding." Any ideas?

Too long without yielding means you're doing it wrong (usually while loops with no sleeps and such), how does that program look?

For simple day/night setting an alarm using os.setAlarm and waiting for it with pullEvent would probably be best

Yes. But keep in mind that IC2 Solar Cells also not operate if it's raining. If you also want to power the querry when it's raining you'll have to use a mechanism to detect rain or a mod (ccSensors) since CC computers can't serve the needed information.

Doesn't tekkit include RedPower? Why not use the light detector?