gres
Full Member level 4
I had found diagram of simple headphones amplifier on TDA2822, and I had a lot of substitutes (KA2209). My dvd player is very quiet, that’s why I need amplifier. All construction takes me one night. System works without any problems. Maybe battery power would be easier, but I had unusefull power supply in very good condition. Voltage of that feeder is 12V, so I need 7809 stabilizer in TO-220 casing. Because of small load and big casing I didin’t need radiator. So paradoxically large casing help to safe space.
Diagram from catalogue notes. Only condensers are different – 1mF instead 470uF. At input potentiometers instead resistors.
Inside. Potentiometer at distance board. If I had screwed it directly to casing I would have had 5mm free space – anesthetic.
Elements that you need:
Casing Z23-A
Double Potentiometer 10kB
Integrated circuit KA2209
Jack plug 3,5 stereo KP3
MTS202 micro switch
Stabilizer 9V/1A
Power slot DC5,5/2/5
Wires, leds, pcb, resistors, condensers.
Building process easy, sound effect very nice. Device doesn’t cut low or high frequencies. Only problem is that it is easy to overstear. While listening music form PC – winamp 100% power and 1/3 potentiometer power deformation is large. Firstly I wanted to limit signal by resistors, but not all device has the same sound level, except that, you have potentiometer – use it!