Completely dead NAD 5000

TheMarco

TheMarco

Thrift Store Audiophile
Subscriber
So I got this NAD 5000 CD player off eBay. Seller wrote it's skipping so I took a chance because it sounded fixable.

I just got it and hooked it up and it's completely dead. Nothing happens when I turn it on.

I have no reason to believe the seller was lying so I'm wondering if there's any basic troubleshooting I can do with this before I ask for a return? Could something have vibrated loose? Not sure where to start.

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Look carefully for a cracked circuit board. (shipping damage ) Cracks usually around any fastener or screws that hold the board in place.
 
Did you look for damage around that little PC board in the rear of the unit, that the power switch is soldered to ?
 
avionic said:
Did you look for damage around that little PC board in the rear of the unit, that the power switch is soldered to ?
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Yup. Looks clean. That orange component measures 7v. That's the only place where I could actually measure any power, besides the actual AC cord when verifying that I was really feeding it 115v.
 
Put your meter on AC Volts and check for voltage on the wires coming from the transformer.
 
TheMarco said:
I guess I'm gonna have to. It's like there's no power anywhere. I'm not very electric savy so not sure what else to try with my multimeter.
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I see two options considering your current skill and knowledge level of electronics and troubleshooting.

1) Return to sender for refund.

2) Use this as a learning experience to increase your electronics and troubleshooting skills.

For option 2, the first step is to download the service manual (HiFi Engine has it). The block diagram on pages 28 & 34 are a good place to start. With the NAD unplugged, trace the circuit from the power plug through the power supply. Identify the actual components in the NAD that correspond to the drawings. Study the drawings to understand how the ac line voltage changes as you traverse the circuit.

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Once you have a good understanding, plug in the NAD and start measuring voltages, starting with the ac line voltage where it enters the case. Don't just willy-nilly poke around checking voltages. Figure out what you should see as a measurement and exactly where you need to measure. A slip of the probe, particularly on the ac line side, can make for a lot of sparks, potentially damaging the unit.

The components between where you measure what you expect and you measure something else are likely where the problem is focused.
 
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RTally said:
With the NAD unplugged, trace the circuit from the power plug through the power supply. Identify the actual components in the NAD that correspond to the drawings.
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That schematic corresponds very well with the posted photo of the secondary circuit.

I'd still start with the mains input; check power is getting into the unit on the 'PS UNIT' board. Check it gets past the switch (they're mechanical, so prone to fail). Should see switched mains across the yellow (Y) and brown (BN) wires.

It's then very easy to check for rectified DC on the bridge rectifier D114; very clear in the photo, and legs easily accessible.
 
I decided to return the CD player and start hunting for a 5100 which matches better with my NAD separates anyway.

Too many audio pieces, too little time.
 
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