It's simple things that get you.
electromanj
Posts: 270
After recieving much good advice from this forum I'm finally able to contribute back. I have made a bs2 oem style board. The stamp part is driving a relay. After making the pcb and soldering all components onto the board I powered it up and to my surprise the thing actually worked...well sort of. I downloaded a simple high pause low pause repeated three times. It went through the first cycle and then stopped. After a closer examination I discovered that I had forgotten one simple thing. The diode across the coil of the relay. After soldering one on I powered up and it's working perfectly!
I hope this helps someone.
I hope this helps someone.
Comments
Well, you get my vote! [noparse]:)[/noparse]
Although I knew you had to have a diode across the coil leads and even understand why because of this forum, I do not know what capacity device you need.
Good work!
--Bill
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You are what you write.
Can you tell me what diode are u using. I also have done my own board and have few relays on it.
The board works fine but there's a little problem that cause my servo to move when I input High to the rlay.
I did'nt use any diode across the relay coil. Mightbe this is the solution.
Thanks for sharing.
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Not only might that be a problem, you run the risk of killing your driver transistor (please tell me that you are using a transistor to switch the relay and are not trying to drive it from the Stamp pin). When a relay "turns off", the energy that was stored in the magnet coil leaves it as the magnetic field collapses. Without a diode, this "back-EMF" has no choice but to try to force its way through your driver...either the transistor or the...gulp...Stamp...doing damage as it does.
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Truly Understand the Fundamentals and the Path will be so much easier...