Hello all,
Another day another amplifier. This time it is a Kenwood Kr-2300 integrated amplifier. The unit I have has a problem where upon initial turn on the unit has a voltage of 20V (yes Volts, not milivolts) on the speaker terminals and slowly goes down to ~.300 - .500mV on the terminals. I have found 1 kinda grainy schematic online, but no service manual.
Here is the following I have done to it:
- Cleaned / dusted it out, it was super dust
-De Oxited all controls just in case there was something wrong with them, didn't change anything but all the controls are scratch free now
-Tested C42 and C41 for capacitance, both were above 1000uF. Replaced them with two 1000uF caps I had on hand with slightly lower voltage ratings (25V instead of 35V) and the problem still persisted. Put in the original Elna caps because no change was noted. As an aside note, would a capacitors ESR increase or decrease the voltage noted on the speaker terminals, or are there to many other factors?
I am kinda stumped here and don't know where to go. I am unsure if this is a transistor issue, or a passive component issue. If anyone has any input / has the service manual floating around your help would be greatly appreciated! Thank you!
Another day another amplifier. This time it is a Kenwood Kr-2300 integrated amplifier. The unit I have has a problem where upon initial turn on the unit has a voltage of 20V (yes Volts, not milivolts) on the speaker terminals and slowly goes down to ~.300 - .500mV on the terminals. I have found 1 kinda grainy schematic online, but no service manual.
Here is the following I have done to it:
- Cleaned / dusted it out, it was super dust
-De Oxited all controls just in case there was something wrong with them, didn't change anything but all the controls are scratch free now
-Tested C42 and C41 for capacitance, both were above 1000uF. Replaced them with two 1000uF caps I had on hand with slightly lower voltage ratings (25V instead of 35V) and the problem still persisted. Put in the original Elna caps because no change was noted. As an aside note, would a capacitors ESR increase or decrease the voltage noted on the speaker terminals, or are there to many other factors?
I am kinda stumped here and don't know where to go. I am unsure if this is a transistor issue, or a passive component issue. If anyone has any input / has the service manual floating around your help would be greatly appreciated! Thank you!