no voltage on X1

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annegerben
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no voltage on X1

Post by annegerben »

I've just finished building my OTGW, but is does not seem to work.
I followed the troubleshooting steps for the website and I have no voltage (1mV) on X1 and pins 5 and 14 of IC1 give 6,2 volts instead of 5v.

What could be wrong?

Update on this,
When I connect the gateway to the computer using usb, I can upload firmware to the PIC
hvxl
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Re: no voltage on X1

Post by hvxl »

If you have no voltage on X1, then there's probably a bad connection on R7, R11, Q2, or X1. It's also possible that Q2 is the wrong component or that it is broken.

A Vcc voltage reading that is too high has been discussed on this forum before. Please look at the information provided in those topics.
Schelte
annegerben
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Re: no voltage on X1

Post by annegerben »

Thanks for pointing me in the right direction.

First I replace Q2, but without succes, after that I also replace Q3.
Now X1 give 24v and 5,9mA
hvxl
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Re: no voltage on X1

Post by hvxl »

Right. My reasoning was that if you only have the components I mentioned, you should already have some voltage on X1. But a short circuit on Q3 could "throw soot in the food" and create the same result.
Schelte
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