Relay Question

[yukanti]

I have this 9VDC relay (attachment)<p><p>the question is:
it's a 5-pin relay... which is output and input?
i've searching for the datasheet, but can't find it anywhere... someone help?<p>one more question... anyone knows what kind of equivalent component that can substitute transistor MPS6531 ?<p>thanks for the helps....

[Yerry]

Most likely:<p>The end with three pins: the two outers are the coil, the center one is the common for the contacts.<p>the other end, one is NC, the other is NO (normally closed & open).<p>An ohmmeter can verify this in seconds.

[philba]

use a simple process of deduction. <p>0) lable all the pins (1..5)
1) 2 pins are likely to the coil. it will have some resistance (coil resistance). write down which 2 have a non-zero resistance.
2) the remaing 3 pins are probably to a spdt switch. One pair should have zero resistance (N.C.) and 2 pairs should be open. Measure and write down
3) set up a circuit to energize the coil with 9V. Then repeat #2. The N.O. pair is now closed should have 0 resistance and the other 2 pairs should be open. The common pin is the one that the N.O. and N.C. pairs both have. <p>The transistor is a general purpose NPN. If you look at the first page of the datasheet, you will see "This device is designed for use as a medium power amplifier and switch requiring collector currents to 500 mA. Sourced from Process 19. See PN2222A for characteristics."<p>Just a guess but PN2222A or 2N2222A should be a decent replacement. I'd think a 2N4401 (03? which ever is NPN) would be good, too.<p>[ March 12, 2005: Message edited by: philba ]</p>