Great you are going step by step and the PCB soldering looks very good.
370uH coil should be fine for testing. Do twist the leads from the coil to the PCB together.
Did you short PL2 pins 1 to 2??? as in step #7.
Do try to beg, borrow or steal an O'scope. This makes testing & adjusting much easier.
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Rev A - Stuck in step 7
Hello, my name is Diego, I'm from Argentina. I recently bought a kit from Silverdog and started to follow the instructions step by step. I've cleared them all until I reached the dreaded step 7. Since I don't have access to a scope I've been doing it just with the help of a Multimeter and a Component tester. The test coil i'm using is made of ~30 turns of 0.5 mm ennameled copper wire with a diameter of 10 cm, I guess it's ok for testing puroposes.
In the video you can hear the high inductance speaker resonating with the coil. The thing is that I can't set the 20K Trimmer (R14) to get -2,1V in pin 1 of U7, it's stuck in 0 volts. I tryed shorting the 3 pins of the 10k delay pot insted of using the pot in the lowest resistance, but it's doing the same thing. When I take out the 10k pot connector, pin 1 goes to -3.20V and if a swing a metal over the coil it goes up to ~-3.06V so I guess it's an indication that the coil is picking up something. I don't know what to do now, I inspected the board and everything seems fine. I'll leave some photos for you to see. Thanks in advance, I know that with your help I'll have a nice metal detector at the end.
The power source i'm using is an old ATX with an output of 11.9V DC.
Board: https://i.imgur.com/PPDebq2.jpg
Board back: https://i.imgur.com/lTH6prQ.jpg
Coil tester: https://i.imgur.com/EGALenm.jpg
Video showing the problem: https://youtu.be/RP8zsKQADHo
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