problem with Mryad CD player

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My Myryad T10 CD player completely stops very frequently. :crying:
The led above the power switch turns off and I hear two relais click,
If I wait for a little while and switch it on again, it wil work for a few seconds up to an hour.

I've opened the case and measured the voltage on one of the PCB's
When the player has fallen out, the voltage of the power supply on the analog part is the same as printed on the PCB
The voltage of the power supply of digital part is less than a volt while it should be 5 Volt. So that seems to be the part with problem.
The main components of the defunct power supplya are: elco of 4700uF, a 5 volt voltage regulator (L7805) and a couple of transistors (A1015 en C1815)

When the player has started working again the L7805 Voltage regulator of the power supply of the digital part becomes very hot, but the is no heatsink mounted on it . (the L7805 of the analog part does have a heatsink but only gets handwarm)

Can anyone tell me what's wrong? I tried to find a service manual but haven't found one. So if there is someone out there that has one please send it to me.
 
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I would replace the 7805 that's been overheating... it may just be that with no contributing factors, and perhaps look to add a clip on heat tab as well. Replacing it proves one way or the other, and these regs can fail in the way you describe.
Also check for dry joints. Those transistors are common low power signal types.
Less likely might be something like a motor (drawer) etc thats trying to run and pulling the rail down but I'm sure you would know about something like that.
 
After an e-mail to Myryad I received a service manual.
This made it a lot easier to measure the voltages.
In a second e-mail I received the suggestion to replace a rectifier bridge.
This seems to solve the problem.

So a big applause to Myryad for their excelent service on an eight year old CD player!!!
 
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