Harman/Kardon AVR (all) free download

File name Harman AVR Receiver Diagnosis.pdf

harman/kardon TECH TIPS Troubleshooting tips and solutions to common service problems TIP# HKTT2004-03 Isolating audio problems in an AVR receiver Using 6/8 Direct In Models covered: The following charts are used to help the tech quickly isolate audio problems in an AVR receiver. Use the following AVR210 AVR310 procedures to help find what is working, then to quickly locate AVR220 AVR320 the problem area. AVR520 AVR225 Equipment needed: AVR125 AVR525 AVR130 AVR230 1 set of (RCA) Y adaptors. Function/signal generator. AVR330 AVR430 Oscilloscope. AVR630 Procedure: 1) Do a factory reset of the receiver. (This will eliminate any common micro processor problems.) Reset List can be found near the last page or check the service website; www.harmanservice.com for the latest info. 2) Print the block diagram from the service manual. 3) With no inputs or speakers attached to the AVR turn on the receiver and turn the volume all the way down. 4) Turn unit off. 5) Hook up an oscillator to the 6/8 Direct in jacks using the Y adaptors. Adjust the oscillator to about 0db (.775Volts RMS). 6) Hook up an oscilloscope to monitor the line out jacks. Or, if there are no line out (preamp out) jacks monitor the input to the power amps or the speaker outs. (AVR125, 225, 130 do not have preamp out jacks) 7) Turn the AVR on. Select 6 or 8 direct in, depending on the receiver. 8) Slowly turn the volume control up until you can easily measure the voltage at the line out jacks. ( -40 to -25db ) Harman Consumer Group 250 Crossways Park Dr. Woodbury, New York 11797 Email [email protected] Isolating audio problems in an AVR receiver Using 6/8 Direct In 9) At this point you will be able to check and assure all output levels are the same. 10) IF THE OUTPUT LEVELS ARE NOT THE SAME STOP! Go no further. At this point you will need to use the charts to see where you are losing your signal. The chart shows the analog signal flow from the input jacks to the output jacks. 11) If the output levels are the same check the power out stage at the speaker out jacks. 12) If you find the levels at the speaker out jacks are OK, your problem will be in the DSP part of the receiver. Congratulations! You have now eliminated 90% of the electronics in the AVR and confirmed that the problem is