Jump to content

Marantz SM500DC power amp issue


Recommended Posts

Hi - wondering if anyone has any idea's - having a issue with my Marantz DC500DC Power amp.

 

Amp powers on - but no sound output - meters not moving - Lights on.

Turning off and on repeatedly eventually gets it going - all good.

 

Leave it on and it works fine - Turn it off and back on works.

 

Leave it off for a few hours - now does not work again - until you repeat the above.

 

Just wondering if a repair is feasible or just leave it turned on?

 

Any advice is greatly appreciated.

 

Thanks

Lance

Link to comment
Share on other sites



Posted (edited)

Sounds like it's not working till after it warms up a bit. This often indicates electrolytic capacitors being out of tolerance for ESR.

 

Check all electrolytic caps for high ESR, especially in the power supply, and the speaker protection relay driver IC.. If you don't have an ESR meter, you'll need to take it to a tech, but is should be repairable without too many dramas.

 

 

SM500DC-sch.thumb.png.d0485577ab9f05d6262a8c718d347ea8.png

 

SM500DC-layout.thumb.png.85cd09c42ef544b004385bde4c437bcd.png

 

SM500DC-sch-full.thumb.png.996c09c98f074f618e15e223ae5d819d.png

Edited by bob_m_54
more info
Link to comment
Share on other sites

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...
To Top