I have searched and found identical posts and referred to snook to no avail. I need some tech assistance. I have steady power 12vdc power supply to relay. My trigger signal is pulsed from a flasher which originally powers LED emergency lights in a quick strobing pattern. I do not know the exact speed or frequency but it is fast with milliseconds in between power pulsed. I have installed an approximate 500uf 35wdc capacitor inline with the signal which has helped slow the relay chattering but not completely eliminated it. The relay is a common Bosch style 35/40 12vdc. Is it the lack of power pulse to sufficiently charge the capacitor to full power or is the capacitor too small to retain enough voltage to supply steady current to relay coil? I figured the relay coil is in the range of 500ma to hold, nominal. I would ideally like the relay to hold steady while signal is sent and draw off of capacitor for a sec or more after input is off. If it stays closed, active, for up to ten seconds is fine too. Any tips, ideas? I want something reliable and the cheaper the better. A few dollars for a simple circuit will suffice, I don't want a $30 circuit to power a few LED's for my specific application. Thanks in advance for any insight.