Arduino Forum

Using Arduino => General Electronics => Topic started by: Bert-CWB on Feb 08, 2011, 03:57 pm

Title: Anyone work out whats on here?
Post by: Bert-CWB on Feb 08, 2011, 03:57 pm
Hi there,

I am trying to figure out exactly whats happening on this board?

It is used to generate a frequency at a voltage which is 12v DC I believe but can anyone work out the components?

Yes I know its in B&W, this is the problem.





Thanks in advance :D
Title: Re: Anyone work out whats on here?
Post by: liuzengqiang on Feb 08, 2011, 04:25 pm
Not very clear why you posted a B/W picture after a color one. The rectangles are possibly relays that are switched on and off by the transistor (black little hat), together, as there is not a second transistor in sight. The black tubes are diodes to prevent some back EMF from the coils on the relays (correct me if I'm wrong). A few resistors for the transistor. I can't tell what the black chips are. No way on your picture. My guess is whatever comes in from the two wires side is power. The chips decide when to turn on the right side with 2 set of two wires. But when to turn on or off depends on what chips they are. I'm guessing they are 555 or something that generates the driving frequency. Who knows, you pics are so poor. ]:D
Title: Re: Anyone work out whats on here?
Post by: Korman on Feb 08, 2011, 04:36 pm

... but can anyone work out the components?


Yes, you can.

Start out by making a circuit schematic by following the traces on circuit board and see what components are linked together. For unknown components make little boxes. This is very obvious and only takes a little paper and a pencil.

Then identify those components you can with the type and the value. This must include all resistors, the relays and the diodes next to them, the transistor and most likely the capacitors. If they didn't sand off all markings on the IC on the track side, you should be able to identify those too.

Last, if that diagram with all components properly labelled is still a mystery to you, make a picture of it and post it here. You'll get a lot more useful feedback that with what you posted up to now.

Korman