Last Gaussmeter Problem? (solved!)

[Jeff Callahan]

Sorry to start a new thread, I find it hard to navigate through the original.

Here's the pics, just to sum it up...
1. I hired an electronics engineer to put this together (I didn't feel 100% undertaking this by myself)
2. I open the box when I got the package to see everything was there, but I did not open the bags.
3. When turned on, it shows blocks on the top row, and is blank on bottom.
4. The engineer who put it together says the chip is defective, or not programmed.

Sorry for the delay elepro, I posted as soon as I could.
Any help, suggestions, or comments are appreciated.

Thanks, Jeff

[David King]

I'd start with the probe wiring. Anyway you can disconnect the probe from the board and see if it jumps back into action?

[Jeff Callahan]

Thanks, I'll try that, I was the impression that the probe would not effect the initial start-up.

[David King]

It just seems that all other problems seem to have come from the probe being incorrectly wired. That would be a natural place to start.

[Joe Gwinn]

Thanks, I'll try that, I was the impression that the probe would not affect the initial start-up.

Unsolder and remove the probe. The unit should then be able to come up normally, but will yield random gauss readings.

Measure the voltage across the probe Vcc and Gnd solder pads. The answer should be very close to 5 volts dc.

These tests will eliminate all probe-related problems, and will also detect power supply problems.

[Jeff Callahan]

I unsoldered the probe and still the same screen, I am not getting 5 volts when I measure the pads. It is the outside two pads, right?

Jeff

[-Elepro-]

I unsoldered the probe and still the same screen, I am not getting 5 volts when I measure the pads. It is the outside two pads, right?

Jeff

yes you must have 5 volt in outside pads.... are you sure you haven't?

[Jeff Callahan]

Yes I'm sure, measured 0 volts no matter what range I used. Does anything in my pictures look problematic?

[-Elepro-]

in picture seems all ok... but could be some micro-cut in pcb trace....
try to take measure in 7805 pads... and then on the cap of PIC (near display connector)

[Jeff Callahan]

I don't get anything in the cap or the 7805. I might be doing this wrong, but can't imagine what. The only volts I get are from the battery itself.

[-Elepro-]

The only volts I get are from the battery itself.

impossible because your display (led+ driver) are on.... try between f and g

[Jeff Callahan]

Go easy on me! I'm sorry, with my limited experience in this kind of work, I failed to turn the switches on. I now have 5.06 Volts when I measure the two outside pad of the sensor. Sorry for the ignorance.

What's next?

Thanks for the support,
Jeff

[-Elepro-]

ok.... do you have 5 volt between 8 and 9 too?

[Jeff Callahan]

Yes, 5.06.

[RedHouse]

Are you certain that your guy handled the LCD module with proper anti-static proceedures? that one-line display thing looks like the LCD module might be fubar.