Ok, then just have them checked out every single component you purchase from "China..." suppliers BEFORE installing them in the circuit.
Otherwise there is just yourself to blame for purchasing fake components.
Hi Dear Friend & Experts,
Finally I replaced all transistors of driver PB 649.
Seems ok. Relay ON after few seconds but now Mute is continuosly not working either touch again and again but no output. Please guide how to do next. I will be thankful to you.
Finally I replaced all transistors of driver PB 649.
Seems ok. Relay ON after few seconds but now Mute is continuosly not working either touch again and again but no output. Please guide how to do next. I will be thankful to you.
No DC on the speaker binding posts. Both PCB (2) relays gets ON after blinking stop on the front panel but the LED just above the volume control doesn't glow. It seems that Mute is not functioning.
There has to be a connection between the"main in" and "pre out" RCA terminals, either metal links or an RCA cable.
Otherwise, no sound!
Ok. Understand.
It has two metal links. I will link them as you suggested. My question is that, will it has some link with Touch Mute button. I bypass this system by removing the collector of related transistor and make the ground jump to relay. Then relay gets ON and the LED also lit up. Even then there is no sound. I am out of my lab for three days. One I join that then I will share the circuit diagram how I bypass the touch mute circuit in the PCB. All three relays gets on after some time and blinking of front LED stops. Anyways really thankful to you for your guidance.
It has two metal links. I will link them as you suggested. My question is that, will it has some link with Touch Mute button. I bypass this system by removing the collector of related transistor and make the ground jump to relay. Then relay gets ON and the LED also lit up. Even then there is no sound. I am out of my lab for three days. One I join that then I will share the circuit diagram how I bypass the touch mute circuit in the PCB. All three relays gets on after some time and blinking of front LED stops. Anyways really thankful to you for your guidance.
Dear Mark,
Thanks for the guidance. Actually fault traced. Referred to Power supply PB647 the connector C07S ...C10S is not generating +- 55 volts reference to ground .
As the variable on the same power supply VR901 & VR902 have no effect even if rotating these. Do you have any clue to get required voltage. Where as all the components are tested and are ok. I think some trigger signal like power good signal initiate these volts from the driver cards PB649 connector C11M ... C18M. Please guide if you know with thanks.
Thanks for the guidance. Actually fault traced. Referred to Power supply PB647 the connector C07S ...C10S is not generating +- 55 volts reference to ground .
As the variable on the same power supply VR901 & VR902 have no effect even if rotating these. Do you have any clue to get required voltage. Where as all the components are tested and are ok. I think some trigger signal like power good signal initiate these volts from the driver cards PB649 connector C11M ... C18M. Please guide if you know with thanks.
I unable to understand that why the power supply is som complicated. Power transistors are derived directly and PB649 the driver stage is through regulated power supply from PB647. Very complicated. In present condition DC of -2.9 volts are going directly to speaker terminal. No separate protection circuit or speaker crowbar protection.
Okay, I think I see where you are looking. Its the same area we discussed back at the beginning of this thread, including the circuit description in the service manual. Its around post #30 of this thread. https://www.diyaudio.com/community/threads/luxman-l-100.412994/post-7691761
I would suggest to go back to that post and to the service manual on page 6, and study what it says. It includes a start-up circuit that has to be working for the power supplies to come up. You shouldn't have turned the voltage regulator pots. Now if you get the power to come back on, the voltage may be too high and cause more trouble. I would suggest to set the pots to the middle of their range to start with. The check the start-up circuit. Is it starting up.
Anyway, you need to read the manual and try to understand the power supply circuit. If you try to understand it and you have specific questions, then I and perhaps others will try to answer.
Beyond that, the power supply isn't that complicated. Also, its unlikely that both the + and - supplies would fail in exactly the same way at the same time. Maybe you should focus on the startup circuit to begin with.
Go back at read the posts at:
Didn't you at one time get it to start up using 4.7k resistor? If so, then why screw around with the voltage adjust pots?
Its important to study that whole page 6 very carefully to understand the power supply. Then look at the real circuit on page 17 of the service manual. The transistor numbers on page 6 and page 17 are the same. Locate Q903 and the other transistors on both schematics, Locate the zener diodes on both schematics. When you understand what the service manual is trying to tell you, then we can proceed.
I would suggest to go back to that post and to the service manual on page 6, and study what it says. It includes a start-up circuit that has to be working for the power supplies to come up. You shouldn't have turned the voltage regulator pots. Now if you get the power to come back on, the voltage may be too high and cause more trouble. I would suggest to set the pots to the middle of their range to start with. The check the start-up circuit. Is it starting up.
Anyway, you need to read the manual and try to understand the power supply circuit. If you try to understand it and you have specific questions, then I and perhaps others will try to answer.
Beyond that, the power supply isn't that complicated. Also, its unlikely that both the + and - supplies would fail in exactly the same way at the same time. Maybe you should focus on the startup circuit to begin with.
Go back at read the posts at:
Didn't you at one time get it to start up using 4.7k resistor? If so, then why screw around with the voltage adjust pots?
See bottom of page 6 of the service manual:
Its important to study that whole page 6 very carefully to understand the power supply. Then look at the real circuit on page 17 of the service manual. The transistor numbers on page 6 and page 17 are the same. Locate Q903 and the other transistors on both schematics, Locate the zener diodes on both schematics. When you understand what the service manual is trying to tell you, then we can proceed.
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You have to decide what you want to troubleshoot first. Do you want to know why there is -2.9 volts on the output, or do you want to know why the +-55 power supply isn't starting up? To troubleshoot, you have to pick a symptom you want to focus on investigating, then just work on that and see where it leads you.
Dear Friend,
First is to find why +-55 volts not present at power supply. From here we will move forward.
Thanks.
First is to find why +-55 volts not present at power supply. From here we will move forward.
Thanks.