Hey Ogdento,what's it drawing for current?
the two rows of blocks on the LCD (which has 4 rows) indicates that the LCD isn't initializing... so I bet the microcontroller isn't running.
It's really just a diagnostic/confirmation check... if it's drawing too much current then the board likely has a blown part.
You'd set your meter to DC current, on the highest range (and use the highest rated input jacks too - some meters have a 10A and a 400mA or similar inputs... use the 10A), and connect it in series with the power supply positive output.
When you measure current you "interrupt" one of the supply lines with your meter. In other words, you would leave the GND from your board to your power supply alone, but "break" the 12vdc supply and connect your meter in between... you connect the neg wire of the meter to the 12vdc supply positive output, and then the pos wire on the meter (the one that's in the current jack) to the board. The current will then flow "through" the meter. Google is your friend here if this doesn't make any sense.
I don't know what kind of meter you have, but if you don't use the highest rated input you risk blowing a current fuse inside the meter..
The power supply is working , I had a 12 v plug laying around I am using. I am really new to this , a picture of what the regulator looks like. What setting do I use on my multimeter. Commercial Electric MS8301B Auto Ranging Digital Multimeter Commercial Electric Ms8301b Auto Ranging Digital Multimeter - Google Search. Any help would be greatly appreciated! This is the power supply I am using.With your board I'd start with the power supply... nothing's going to work until you can get 5vdc out of the regulator.
Test the inputs/outputs of the two bridge rectifiers (BR1, BR2), and the output of the 5v regulator (U2). Then do the current check I mentioned above... if it's too high, pull those two socketed uln2803 chips (transistor arrays that drive the relays) and test current again. If it's still too high you'll want to look for shorts and start testing parts, and I would pull the lcd so I could then pull the comm chip. A thermal camera comes in handy at finding parts that draw too much juice - they heat up!
If you get the power supply working, with some fairly inexpensive tools you can sniff the outputs of the real time clock, the comm circuitry, and the lcd while you're at it. You can do a lot with these boards without ever hooking up the 18/24ac input.
I don't have any videos but I've posted a bunch of info here, probably more to come since we're all stuck at home
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Tinkering with Electronics
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