Repairing an SMPS, taking apart my camera and Earthing

Today was pretty awesome. Since I started studying SAP/ ABAP , there is only two days left for myself each week. Today the SMPS that was repaired have been powered up, the Canon A710IS has been opened and got myself back to the earthing thing I had postponed for months. I have a tendency to postpone things and usually will not get some stuff done, ever! Considering that, it was rather good today.

SMPS repairing

I have about 6-7 computer power supply lying around. Two my own, one from a friend, and the rest from a computer shop of my neighbor. All are broken and most of them are crappy low cost ones. They usually have a common schematic that is widely available on the new. Here is the schematic for those who have yet to find it. Since the SMPSs are from different timeline, the degradation of quality is profound. The first ones used rather good quality capacitors and the input had a connector and fuse holder. The later generation ones have got some of the worst Cps I have seen, does not have the input connector and the fuse is soldered directly to the PCB. And last but not lease, there is NO EMI filter!

I am all for low cost, but cost cuttings should always come after quality assurance. And this is exactly why I hate places like India and China. we build the cheapest and lowest quality goods, throw them away once it breaks down, thus increasing the resource usage and littering. This is why low cost products suck. I will write more about the SMPSs later.

All I did was replace all the electrolytes with some quality ones available. I was pretty sure it was the electrolytes because one was blown and electrolytes in SMPS are famous for dying an early death. Everything went fine, I shorted the Green (Power ON’ ) pin to GND (Black) and voila, it just powered up. Always feels great to see things work.

Canon dissection

My digital camera is a Canon A710IS brought from the UK (my sister bought when she went to UK). I grabber a screw driver and finally opened it up. And it was rather neat. I have some PICs. All are extremely low quality since they are from a webcam.

Canon A710 IS LCD and buttons.

Canon A710 IS lens, AF assist and motor.

Canon A710 IS Lens closeup

As expected, the design was brilliant. I always admire the people who design enclosures, products. There is certain amount of sex appeal for a well designed and assembled product. And I am a fan.

Earthing.

About 4-5 months ago, my PC Power Supply, motherboard and HDD got damaged. It didn’t occur to me that it could be a ground fault. Ground faults are famous for causing RAM damage (I do not know the truthfullness but it seems so). But when the New SMPS that I installed also was damaged, I thought about the earth connection. And, it turns out, our electrician had done an amazing job of earthing – 2 feet 1/2 inch GI pipe driven to earth connected to the Mains ground by a 1mm copper wire. If he was around when I found this out, I would have shot him. WTF was this. A 1mm single strand copper that is more than 100ft total would never carry much current. So I decided to do a new earthing myself. In the end I have about half a meter square pure copper sheet burried with three 4mm copper wire connecting it to the mains ground. The total distance of this from my PC has also been reduced greatly.

The final connection was made only today, and now I need to power up my PC after a looong time. All this time I have been working on my laptop. Powering up the PC means I can get much more involved in electronics, mainly because it would provide a ready RS-232 port and a full table to work on.