Marantz DVD player power supply fault?

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Hi there - I have a marantz dv6400 which has just given up the ghost. the problem is on power-up, i suspect is a PS prob. there is a push button start, lately it has been shutting off by itself instantly and took several hits of the power buttin to get going. now it momentarily powers up and shuts down instantly and doesnt stay on at all.

There is a strange noise coming from the PS section of the PCB for the brief time the unit stays on, kind of a high pitched squealing noise. the suspects where the noise could be coming from are a 33uF 400v electro PS cap, an inductor which is just in-line after the 240v input, and the transformer.

I think i have heard capacitors make funny noises sometimes? my suspicion (after i read this on the net) is the electrolyte in the cap has dried up and it has stopped working. i reckon this coud be the prob as i have consistently left the unit on for about the 3-4 yrs i have owned it - maybe not the best.

Would the best be to replace this cap and see how things go? Any help much appreciated!
 
Judging by the low weight (2.2 kg) and low stand-by power consumption (0.4 W) I'm assuming the DV6400 has a switch mode power supply (SMPS).

These are known to make squealing noises if there is a fault (often this happens when there is an overcurrent). Yes, it could be the capacitor you mention but IMO it's also possible something else has failed that is now drawing too much current. Overcurrent trips the protection of the SMPS and makes it switch off.

It's not only caps that can make noise. Esp. switching transistors or coils/transformers can also be pretty noisy (and a SMPS has them too).

It's cheap and relatively easy to put in a new cap and see if the problem persists or not. If not :up:, otherwise things become more tricky and you should first try to find out if the cause lies in the SMPS or another part of the DVD-player.
 
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