Hi Jordan, Love your commentary in video, very informative. I have a Rotel 985MK1 with one dead channel. And fluctuating DC on output(0-4V). I checked all the power and driver transistors and non of them are found faulting. Opamp is fed with +15 and -15 and one of the outputs from op amp is almost at around +/-15v. I swapped this op amp from a working channel but still the same issue. All resistors, electrolytics test ok. Styroflex capacitors are not checked(Could these cause such problem). Kindly help me with any lead on where can i start troubleshooting. I am just a hobbies and have little experience fixing.
Hi Nadimpalli Thank you for the comment, I'm glad you enjoyed the video, Part 2 will be out shortly! Without looking at your amplifier directly it is possible that a bad styroflex capacitor(s) could have something to do with your issue . In my amplifier on the video it had a few of these on the 49v rail near the transistors responsible for bias. I would not suspect an opamp to cause DC on the speaker terminals, I'd be looking further down the chain. When you check the bias test point with your multimeter on DC what does it read? Please be carful when working on your amplifier, you could get a nasty shock from charge stored in capacitors even when switched off,. Having said that I'm sure you know this if you have come this far. Talk to you soon!
@@jordanclarke2996 sir, could you please share me the voltage details of the rotel RA 971 toroidal transformer, mine transformer got blown up. So i have to wind new one, in online and in service manual not able to get. I got part number . Can you help me?
Hi Jordan,
Love your commentary in video, very informative.
I have a Rotel 985MK1 with one dead channel. And fluctuating DC on output(0-4V). I checked all the power and driver transistors and non of them are found faulting. Opamp is fed with +15 and -15 and one of the outputs from op amp is almost at around +/-15v. I swapped this op amp from a working channel but still the same issue. All resistors, electrolytics test ok. Styroflex capacitors are not checked(Could these cause such problem). Kindly help me with any lead on where can i start troubleshooting. I am just a hobbies and have little experience fixing.
Hi Nadimpalli Thank you for the comment,
I'm glad you enjoyed the video, Part 2 will be out shortly!
Without looking at your amplifier directly it is possible that a bad styroflex capacitor(s) could have something to do with your issue .
In my amplifier on the video it had a few of these on the 49v rail near the transistors responsible for bias.
I would not suspect an opamp to cause DC on the speaker terminals, I'd be looking further down the chain.
When you check the bias test point with your multimeter on DC what does it read?
Please be carful when working on your amplifier, you could get a nasty shock from charge stored in capacitors even when switched off,.
Having said that I'm sure you know this if you have come this far.
Talk to you soon!
@@jordanclarke2996 sir, could you please share me the voltage details of the rotel RA 971 toroidal transformer, mine transformer got blown up. So i have to wind new one, in online and in service manual not able to get. I got part number . Can you help me?
@@jordanclarke2996rotel ra 971 toroidal transformer secondary voltage and ampere specification?