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jimfun
03-28-2005, 12:44 AM
Hope everybody had a nice Easter. Visit with the family, get closer to God, or just relax. However you spent your Easter I hope it was good for you.
I also need some eletronics help. I bought a steper motor controll kit. It's one of those little ones. Came with a little motor and circuit board and all electronics and what is the worst assembly instructions I have ever seen. I was hoping that it would explain all the workings of the board...yea right...it bearly identified all the parts. Anyway...I have two parts that I don't know which pin is the positive lead. If anybody can identify the pos lead I would be greatly appreciative. Thanks a bunch, http://bbs.homeshopmachinist.net//biggrin.gif
Jim
http://i2.photobucket.com/albums/y7/jimfun/electronics.jpg

JRouche
03-28-2005, 01:06 AM
Looks like a transistor and what? A diode? Dunno?

The switch can be used as designed. Oh right, alotta help there, no papers.

Basically the base, collector and emitter.

Scavenged transistor test (it's fairly simplistic if you think about the circuit).
JRouche

"""Testing a transistor with a multimeter

Testing an NPN transistor
Set a digital multimeter to diode test and an analogue multimeter to a low resistance range such as × 10, as described above for testing a diode.
Test each pair of leads both ways (six tests in total):

The base-emitter (BE) junction should behave like a diode and conduct one way only.
The base-collector (BC) junction should behave like a diode and conduct one way only.
The collector-emitter (CE) should not conduct either way.


The diodes are reversed in a PNP transistor but the same test procedure can be used."""

3 Phase Lightbulb
03-28-2005, 01:08 AM
The 7805 is a 5V voltage regulator.

Pin 1: Input
Pin 2: Ground
Pin 3: Output

Pin 1 is to the left.. In your image, Pin 1 is under the "7". Pin 2 is in the middle. Pin 3 is to the right.

The

jimfun
03-28-2005, 01:27 AM
I used all the parts but these two. Yes the 3 piner is a 7508 the 2 piner is suposed to be a .001 uf cap. I need to know the positive pin on both of these so I can finish soldering these into the board.

3 Phase Lightbulb
03-28-2005, 01:34 AM
<font face="Verdana, Arial" size="2">Originally posted by jimfun:
I used all the parts but these two. Yes the 3 piner is a 7508 the 2 piner is suposed to be a .001 uf cap. I need to know the positive pin on both of these so I can finish soldering these into the board.</font>

The cap is just a little decoupling cap that isn't polarized so it should not matter.. The 7805 is a voltage regulator. Pin 1 on the 7805 would connect to the Positive side of your power source, Pin 2 is the common ground, and Pin 3 is the regulsated output +5V that will power your stepper controller. Pin 2 is the common ground on your Input (+5-+12v) and is the same ground for the +5V output (pin 3).

-3Ph

jimfun
03-28-2005, 01:43 AM
Thanks for the help. It is greatly appreciated. Now I can finish this project. Can't wait to see if it works.