Sharing information on its completions SDS8202
1. Tired of cheap fan noise. I had to change. The original 60h60h10mm, 12V, 0.2A, powered by 8.4V. It was fixed at the bottom of the metal radiator. In order to reach and change, I had to disassemble 90% of the oscilloscope including a trail of the film, which is very much did not want to disconnect.
As a replacement was selected
http://www.citilink.ru/catalog/computers_and_notebooks/parts/coolers/944770/Which had good reviews on work and noise, but had 60h60h12mm sizes.
Despite the fact that there were doubts whether it will get thicker fan and even on top of the metal-housing land (so that you can replace it without total analysis of the oscilloscope), all successfully. Fans 12mm thickness fit overhead. I had just rewire the power connector from the fan, replacing it with the old one.
However, I think this is still a temporary solution, because I do not see anything too much energy-intensive, that is hitting the fan. Only 2 cases, which suggests to put in place an ordinary radiator fan, although the question remains open of the fastening of a radiator.
I would be very grateful to those who have shown the interior of the oscilloscope with a passive cooling system in the new revisions of the oscilloscope.
2. Current 15mA from the battery in the power supply in the off position, I also did not suit, with the result that I have been able to reduce it to 3mkA using SMD diode Schottky B320B, designed for permanent and 3A to 100A per pulse (which has been removed from the motherboard or graphics card).
It looks like this: (1 photo)
Rosin flux, which the power supply board was just filled, it was necessary to wash long and hard alcohol.
The voltage + VDD to the power supply unit connector terminals 5,6 and plug the battery, of course, it dropped to 8.23V. I began to look divider that controls the setting of + VDD. And here I was waiting for the first TH. The scheme, which I was not consistent with my power supply. (Figure 2)
My power supply is labeled PCB-T115-J Rev6 it lacks the LM393, LM358 is used instead of a quad LM124, a resistor, performing the same function are labeled differently, J2 switch is not paired contacts, but in general a lot of differences. However, I managed to find a resistor that is responsible for voltage control - it was R17, which was parallel to the empty space to install R18. the selection method has been found that setting in the ready-made holes resistor denominated 33kOm, managed to do exactly equal to + VDD 8.4V. (Photo 3 of this resistor location showed a red arrow).
However, the scheme is written that is also required to recalculate R34, R38 (the threshold of extinction of the red LED - charge indicator) for a complete revision. But on its power supply analogues of these resistors I found it was not possible. So the question is: Is someone these dividers on its power supply if they have the same PCB-T115-J Rev6 like me.