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Hi, Michael!
I received you clock, all was packaged perfect. I solder all, checking several times polarity and chips orientation. Use only 6 AA batteries and several times check polarity (central positive). Then lots of bugs begins.
1) First switch on: display shows all 0000, then 3-d digit blinks shortly and still never work. I never hear beeper. All buttons (alarm, det, hour, min) doesn’t work.
2) Diods near DET button and alarm never lights. “Alarm” diod blinks several times (actually I didn’t understand, what must to do to make it blink – seems it blinks randomly). DET diod shows nothing – no lighting, no blinking.
3) No light on top dot between “hours” and “minutes” digits
4) Voltage regulator is extremely hot and both 4 transistors above LEDAfter resoldering (did it accurately and will send you pictures this weekend) LED works, but only bottom right “element” of each digit, regulator extremely hot, and after 25 sec of work one of semi-round transistors above LED burn (I hold board and see small blink of fire on the opposite side of it where I solder items).
I,m not an engineer and understand nothing in electronics, so I’m very sad. I can send you photos and send assembled unit back, so you can check it. I beleive you make a great device but need your help.
UPD: I find a shop with lots of components near my house, so may be you can help me with an advice, what’s wrong and send me list of components you use (with tipes of components, specifications and indexes to buy). So I can show it in shop and choose component I need.
It sounds like there is a short between +5V and GND. If the voltage regulator is very hot, then something is very wrong. Some components are probably damaged, so it’s not worth trying to repair the clock.
Since you are in Russia, you don’t have to send the unit back. I will send you an assembled/tested replacement. Sorry for the bad luck.
I’ll send you photos, may be I did something wrong… I really solder all very carefully and cool the front side of the board with components with a cold fan all the time. No big leaks or drops of soldier and soldered together nearby units 🙁
That sounds good. It is possible that the board had a defect and caused a short. Or, sometimes a little extra solder will cause a short to the ground plane if the solder mask is melted away a little bit. Or maybe one of the transistors was defective. I’m sure you were careful, but these things happen sometimes.
endlessplanet, your soldering looks good. I think your microcontroller may have failed. I will ship you an assembled/tested defusable clock. Sorry for this inconvenience and delay.
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