June 12, 2014 at 11:21Treat Chinese usb audio card
I ordered two USB audio cards for a long time (they are listed on them as “Virtual 5.1 Channel Track 3D External Mic Speaker Audio Sound Card Adapter”):
But for some reason they were afraid of removing it “hot” from the PC. As a result, one failed, and the second after the same symptoms and soldering still managed to be restored. To this day, it is not removed from the PC and works.
Photo of motherboard number 1 (without two capacitors (100mkFh10V), they will be discussed below):
However, the second PC was left without sound. I ordered 3 more cards from different sellers. They came all as one (identical boards), but not the same as in option No. 1. Board number 2:
When checking, it turned out that it works well with monitor headphones and speakers with an amplifier, but there was a lot of noise with mobile headphones (earbuds, drops, etc.). Apparently, the matter is in resistance, for monitor headphones it is two times higher than mobile, and for an amplifier it is thousands +.
If you look closely at the board number 2, you can see the holes for the capacitors C4-C5 (the polarity is indicated by silkscreen), but they are not. Capacitors (100mkFh10V) were soldered from the board number 1. I did not immediately pay attention, but the contacts of the capacitors are closed between each other by a track:
It must be cut, and the capacitors soldered according to the polarity.
After the above manipulations, the audio card began to work properly - the noise disappeared.
By the way, the option of the audio card No. 2 turned out to be more resistant to extraction "hot", although it may still be lucky ...
But for some reason they were afraid of removing it “hot” from the PC. As a result, one failed, and the second after the same symptoms and soldering still managed to be restored. To this day, it is not removed from the PC and works.
Photo of motherboard number 1 (without two capacitors (100mkFh10V), they will be discussed below):
However, the second PC was left without sound. I ordered 3 more cards from different sellers. They came all as one (identical boards), but not the same as in option No. 1. Board number 2:
When checking, it turned out that it works well with monitor headphones and speakers with an amplifier, but there was a lot of noise with mobile headphones (earbuds, drops, etc.). Apparently, the matter is in resistance, for monitor headphones it is two times higher than mobile, and for an amplifier it is thousands +.
If you look closely at the board number 2, you can see the holes for the capacitors C4-C5 (the polarity is indicated by silkscreen), but they are not. Capacitors (100mkFh10V) were soldered from the board number 1. I did not immediately pay attention, but the contacts of the capacitors are closed between each other by a track:
It must be cut, and the capacitors soldered according to the polarity.
After the above manipulations, the audio card began to work properly - the noise disappeared.
Photos of cards redone in this way:
By the way, the option of the audio card No. 2 turned out to be more resistant to extraction "hot", although it may still be lucky ...
