possibly conflicting info, cap values

i have been back around the site for a few days to find more answers.however i have come across some information which seems to be a little confusing.on a relay circuit diagram i find the use of a 10K uf capacitor. This seems a little high. And the size is not quite readily available to buy in public stores. It has also been stated in one of my previous posts by another member that this value i am seeking seems to be very high. It was suggested to me to try a smaller one.here is the link for the diagram... pulsed to steady output...calling for the 10K uf.upon further reading i find that the capacitance values are different in another application and times are stated for expectant voltage holding...this is found here.... time controlled circuitcould someone clarify this to me please.i am failing to grasp where such a large difference could be.i'm probably not even asking this right but i do not want my project to fail and buy the wrong value of parts.any help much appreciated.thanks

Two completely different circuits. The first is using a relay. The second is using transistors. No conflict in information at all. The coil of a relay will require a much larger capacitor to stay energized for the same duration of time. the12volt • Support the12volt.com

ok. i see. thanks for clearing me up on that there 12volt. and by the way...great site....masses of information.