where to connect audio input on the chip of XR-3324


2010-01-08 7:14 am

With your help i got XR-3324 Manual (Perry helped me).

I tried to input(from a mp3 player) using 3(LFIN), 34(RFIN) and 21(GND) but audio quality was not good. then i tried with 11(LTOUT), 26(RTOUT) it worked, but the volume control option is not working. Though i change the volume it doesnt affect.
I have to adjust the volume in my mp3 player.

Can anyone please help me where to connect the left, right and ground, (audio input ) on the PCB.
I have attached Chip Diagram
If you need the Service Manual below is the link




  • IC402.JPG
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Have you checked the output level of your MP3 player and compared that to the input level spec of the chip you have posted. most likely you dealing with a level mismatch issue where your Mp3 player output is either too high or a mismatched impedance issue..... it appears that you selected the correct input pins to begin with, so this is why I jump to the conclusion that there is a signal level issue.
Another possibility is a DC offset issue, are you capacitor coupling your connection to block any strange DC offsets that may be occurring ??? if I were you I would not be making any direct connections without the use of a DC blocking cap inline with the signal before it enters the HU circuitry....hope this helps some...:)
On IC501, solder a bridge between pins 1 and 2. Solder another bridge between pins 6 and 7.

Break connections to the tape head at points 9, 10 and 11 on CNP901.

Connect the RCA shield to the line that was connected to pin 10 on CNP901. Insert a 10uF cap between the RCA shield from the mp3 player and the circuit. The value is not critical but the positive terminal has to connect to the op-amp side of the circuit.

Connect the left and right signal lines to the side of C501 and C502 that were originally connected to pins 9 and 11 of CNP901.

You'll have to insert a tape to get the audio to switch to cassette.

Don't expect it to work perfectly. It will likely take a bit of tweaking to get it right.