Re: Yamaha RX A3020
Fascinating.
At 50 degrees C, DSP1 (IC911) is happy, everything works,
at 45 degrees C, it stops.
Regular and repeatable.
Using a thermostatically controlled heat gun, I baked the chip at 150 degrees C for 15 minutes.
So far the bakeout appears to have been successful and all channels are running again.
Thanks SlimMoses !
Andrealikescaps
Member
Last Activity: 06-15-2023, 12:29 AM
Joined: 12-31-2013
Location: Perth
-
Re: Yamaha RX A3020
C2.1 on this one is network check. Shows all ok so long as you connect it to a network switch.
C1.7 however is more interesting as it shows NG.
BUS DSP1 is reporting an error then.
IC911 on the DIGITAL (1) board.
Will take a look around there.Leave a comment:
-
Re: Yamaha RX A3020
Thank you for your questions.
I'm testing with the tuner input.
I have access to a function generator.
I have a scope.
Not checked pre-outs.
Display output is normal, no errors, not in fault mode....Leave a comment:
-
Re: Yamaha RX A3020
No BGA's fortunately.Leave a comment:
-
Re: Yamaha RX A3020
Thanks Victorcas, no sign of liquid spills, but just in case I sprayed out the boards with IPA and compressed air.
Removed quite a bit of dust but unfortunately the problem remained unchanged until....
The circuit shows Q1810 and Q1809 conduct the entire +-60V supply to the amplifiers.
So they are likely to run hot anyway, so I'm putting that down as a red herring.
For the sheer pleasure of it, i went through the Idling current adjustments.
Once this was complete and all the channels were within the 15+-2mV spec...Leave a comment:
-
Yamaha RX A3020
Hello friendly Badcaps community.
I have one of these on my desk today, and I have attached a [URL="https://elektrotanya.com/yamaha_rx-a3020_rx-v3073.pdf/download.html"]service manual[/URL] if it is beneficial to anyone.
It turns on OK but no audio output to speakers unless the 'pure direct' button is pressed, and even then after 30 seconds, audio stops.
There is no relay click when the sound stops, so not a relay control problem.
Headphone audio stops when speaker audio stops, so not likely a power amp problem.
It does not appear to be in any protection... -
Re: RME Octamic II input circuit anyone
BTW if RME ever get around to reading this post (they said they would when I contacted them), please understand that sharing technical information on your products helps to increase your standing in the community. This has value beyond measure if you want to survive in the long term.
This is something you will learn if you stay in business long enough.Leave a comment:
-
Re: Pioneer Magnetics PM33 5000W switchmode supply
No takers i see, well Meanwell make similar supplies so I will look into shoehorning one in for now, but if anyone in Australia would like to try to repair one of these supplies I'm happy to offer to pay.Leave a comment:
-
Re: RME Octamic II input circuit anyone
"That 1510 preamp IC" was indeed the problem. Replacing it fixed all.
Unfortunately this preamp has left the building jantoman, so it can't pose for a picture, but when another comes in I will take a picture.Leave a comment:
-
Re: RME Octamic II input circuit anyone
"That 1510 preamp IC" may be the problem.
Tis an 8 pin package.
Pinouts and recommended circuit attached.
I measure:
Pin 1 Rg1 -9.8VDC
Pin2 -in -9.1VDC
Pin3 +in -9.1VDC
Pin4 V- -15V
Pin5 Ref 0V
Pin6 Out 0V
Pin7 V+ +15V
Pin8 Rg2 -9.8VDC
So. How is it possible for Rg1 and 2 to have a higher (absolute) potential that +-in other than the chip is faulty and conducting some of the -15V supply to Rg1 nad 2.
Does this seem plausible...Leave a comment:
-
Re: RME Octamic II input circuit anyone
Thanks again. I have measured the same voltages at the board as on the Caps can. I know there isn't necessarily a hard connection to the can, but it makes an easy measuring point, besides for a high impedance voltmeter, 1Mohm is no obstacle to measurement.
The stray 9V seems to be coming from the IDS connector pictured, 5th pin from the top right.
I'll pull the front panel board, also pictured, and follow this stray DC voltage in.
You are correct. The 1G transistor is 48V power feed and since that is disconnected,...Leave a comment:
-
Re: RME Octamic II input circuit anyone
Thanks for the suggestions. I've uploaded more photos. No signal on ADAT or analog output on channel 4. All the rest OK.
All the caps except the largest and smallest on the left have around +9VDC on the can, as pictured.
Disconnecting the 48V power feed to the board does not make the stray 9V go away, so not caused by those diodes. Removing the ADAT board makes no difference either.
To answer Capleakers sensible question, there is nothing under the board as pictured. The 3 legged device is marked "1 GM"...Leave a comment:
-
Re: RME Octamic II input circuit anyone
Thank you Khron, is this photo ok?...Leave a comment:
-
RME Octamic II input circuit anyone
Hello Badcappers.
I just finished wasting time contacting RME for any useful information on the Octamic II preamp. We have been repairing these for some years (with no help from RME). These are expensive devices with cheap unreliable components inside. Caveat emptor.
Anyway, we are managing to repair them all the same, usually by replacing the dodgy switchmode power supply with something reliable, but recently I thought it would be nice to actually repair one of these devices, rather than replacing boards in them. A likely candidate came along with just one channel out of 8 showing... -
Pioneer Magnetics PM33 5000W switchmode supply
Hello friendly Badcaps community. I'm repairing a 5000W switchmode power supply. Pioneer Magnetics are being incredibly unhelpful, so I'm all the more determined to fix it anyway
. Would anyone have experience with these supplies or know where a circuit diagram may be found?
Cheers. -
Re: Board view for Asus UX32VD Rev. 2.1 60-NYOMB1100-C02
Hi folks. I've tried those board view files & can't run them in windows and linux using OpenBoardView R534. Any possibility of their being corrupt? I'm just looking for the charge circuit?Leave a comment:
No activity results to display
Leave a comment: