Ren4Flood

[Hogfather]

Okay, I am at a lose. The LED is not lighting up and I confirmed it is installed the right way. I get zero voltage on the PIC (pins 1 & 14) or either RS-485 sockets (pins 1 & 8). I've tried two different power supplies (12v & 18v). I inspected my solders even resoldered the capacitors and regulators.

The weird thing is that I have the DIYCFlood already attached and whenever I power the board 12 of the LEDs light up and stay on (6 reds and 3 blues). That boggles me.

Any suggestions?

[budude]

It sounds like there is a problem with the regulator - measure the input between pins 1 & 2 - it should match the input at the terminal block. Measure the output of the regulator at pins 2 & 3 - it should be 5v but I suspect it's probably 0. Check if it's hot - it may be trying to power up but you may have a short. Follow the +5v trace around the board looking for shorts (it's a fatter trace so easy to follow). I suspect your oscillator might be installed incorrectly as well - double check the orientation - the squared corner should be pointing to the lower right (there is an "arrow" point to it on the silk).

[chelmuth]

Photos are always helpful too if you have the ability to take some.

[CaptKirk]

This bit me in the butt- the pinout for all voltage regulators is NOT the same. Standard voltage regulators vs Low Drop Out (LDO) is very different. You might want to check the pinout for the regulator you are using vs the one called for on the BOM if you got a different one!!

[budude]

It should be a standard 7805 - normal IN/GND/OUT pinout...

[CaptKirk]

Yeah and I got "smart" and ordered some LDO and they are GND/OUT/IN and you can make them work if you cross pin 1 and pin 2 and then insert the device backwards from the standard way you would install a non LDO regulator. *OR* you can also install forward but shifted over one set of pins then bringing pin 3 back over to pin 1 like the pic (red is a wire)
to220_LDO_to_VR.jpg

I *believe* this will work. can anyone verify??