Well Guys, I was messing around with my tank today and had to remove the lighting to gain access. When got everything back together and reconnected the power I noticed something weird. Two out of the three SmartyCats would not turn the leds back on. I rechecked all my connections and could find nothing wrong, so I figured the problem had to be internal to the SmartyCats themselves. I connected them to my PC and soon found that the System time had been reset to an earlier time? I did some further checks and found that the DS1307 RTC's weren't keeping time with the power interrupted. After another hour or so of trouble shooting, this is what I found- There's a defect in the PCB at the DS1307 RTC. Pin #7(SQW), which should have been left "floating" according to the schematic and PCB design files, is in reality grounded
. This defect was not caught at the PCB factory and may be present in some of the SmartyCat's that some of you are using. I found the same defect in 2 more of the units that I haven't even built yet.
If any of you guys notice the same problem with the clock, here's the fix- Remove Pin#7 from the DS1307 and the problem will be fixed. I used a fine point soldering iron to heat the pin and a small jeweler's screw driver to lift the pin from it's pad. Here's a photo-
If your unit suffers from this defect and you can't tackle the repair yourself, send me a PM and we'll make other arrangements.