I moved a circuit from a breadboard to a standard generic PCB prototype board, and the circuit didn't work on the PCB board. Specifically, a small Arduino Wifi device wouldn't even boot while it was on the PCB board.
Naturally, I checked all of my solder connections under a magnifying glass and I triple checked the wiring to make sure it was consistent with the schematic. This is a VERY SIMPLE circuit ... maybe a total of 10 wires are involved at the most ... a couple of pins, a transistor, couple resistors, and an LED.
Ultimately, I discovered that I was getting voltages in some cases almost 2 volts on pins that weren't even connected, so I went through a process of elimination to try and isolate where the voltage was coming from until I accidentally placed my meter onto one of the circles on the board that had nothing on it at all and read 1.6 volts. So then I checked about 15 more various points on the board that was not connected to anything and I was seeing the same voltage... so then, I realized that this stray voltage that seems to exist over the entire board would easily explain why the circuit is not working.
My question is: Is it a known or common problem for these prototype boards to do this? I have no idea how they could possibly conduct electricity to all of the pins on the board when they are specifically engineered to have electrical isolation between connection points.
I did try two other boards that I had laying around, and I pre-cleaned them with rubbing alcohol but got the same results. Granted, these boards I've have in my stockpile for a few years, but that shouldn't cause this problem, should it?
Here is a sample of the board I'm talking about:
Thanks for your feedback,
Naturally, I checked all of my solder connections under a magnifying glass and I triple checked the wiring to make sure it was consistent with the schematic. This is a VERY SIMPLE circuit ... maybe a total of 10 wires are involved at the most ... a couple of pins, a transistor, couple resistors, and an LED.
Ultimately, I discovered that I was getting voltages in some cases almost 2 volts on pins that weren't even connected, so I went through a process of elimination to try and isolate where the voltage was coming from until I accidentally placed my meter onto one of the circles on the board that had nothing on it at all and read 1.6 volts. So then I checked about 15 more various points on the board that was not connected to anything and I was seeing the same voltage... so then, I realized that this stray voltage that seems to exist over the entire board would easily explain why the circuit is not working.
My question is: Is it a known or common problem for these prototype boards to do this? I have no idea how they could possibly conduct electricity to all of the pins on the board when they are specifically engineered to have electrical isolation between connection points.
I did try two other boards that I had laying around, and I pre-cleaned them with rubbing alcohol but got the same results. Granted, these boards I've have in my stockpile for a few years, but that shouldn't cause this problem, should it?
Here is a sample of the board I'm talking about:
Thanks for your feedback,
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