Hi guys hope you all doing fine.I have an Onkyo HT-R960 from my uncle that he says he powered it on one day and no sound at all.I took it to try and repair it.I am also using it as an opportunity to start learning how to repair units like these and also amplifiers. When i first brought it home I also realized it wasn't outputting any video and audio tru the HDMI Ports.So followed a youtube video on how to change 5 caps to get HDMI output back.Did exactly that and now i have Picture tru the HDMI Ports.But still no audio. Checked a lot of voltages according to the schematic and also visually nothing looked burnt or any swollen caps on any of the boards. Read on another forum someone saying that if i have voltage on the ''AMUT'' and ''SMUT'' lines this will mute the audio.I measured AMUT and SBMUT and yes i had 4.9v on both lines....So removed all of the MUTE Transistors x9 of them.And measured again and 0v on SBMUT and still 4.9v on AMUT.
I connected speakers and sent audio tru the CD Input and started getting sound on Front Speakers B only. No Sound from Front Speakers A. According to the schematic SMUT (which is 0v now) is connected to the Front Speakers B. But AMUT (which is 4.9v now) which is connected to Front Speakers A gives no sound at all. So I can't understand why AMUT still has voltage on it.Hoping you guys when u have time can check out the schematic and guide me on some things to check in case i might of missed some things. Thanks.
I did all the basic troubleshooting already like factory resetting the unit and checking all cables.I also used a wire and touched the ends with my finger to inject 60hz frequency into the Tone Control IC output to make sure there is a connection straight to the speaker terminals. And yes all traces are fine and cables properly seated. i have a screenshot below of the schematic layout.
I connected speakers and sent audio tru the CD Input and started getting sound on Front Speakers B only. No Sound from Front Speakers A. According to the schematic SMUT (which is 0v now) is connected to the Front Speakers B. But AMUT (which is 4.9v now) which is connected to Front Speakers A gives no sound at all. So I can't understand why AMUT still has voltage on it.Hoping you guys when u have time can check out the schematic and guide me on some things to check in case i might of missed some things. Thanks.
I did all the basic troubleshooting already like factory resetting the unit and checking all cables.I also used a wire and touched the ends with my finger to inject 60hz frequency into the Tone Control IC output to make sure there is a connection straight to the speaker terminals. And yes all traces are fine and cables properly seated. i have a screenshot below of the schematic layout.
Attached Files