Faulty Naim CD player.

[Luca]

Thank you all for the advices and warnings.

Saturday afternoon I found time to check and measure all with calm.
I turned on the player and after five minutes the problem recurred ... the NADI led went off again. This time I kept the CDI switched on several minutes to measure all the voltages until I found another problem. One of the two heatsinked LM317 runs much warmer than the other and two caps look darker (seem cooked). The voltages on the pins of these two regs are the same and I'm wondering if the hotter one runs on more mA to justify a higher temperature. If not, the concerning caps are a problem that have to be serviced ASAP.

20210828_154743 by Luca B, on Flickr

Casually, while I was touching the heatsinks to check the temperature the NADI led recame back on and all started working again. In the evening, I listened to some Haydn's concerts without issues.

I think that I can't put off a capacitors replacing and I'm going to place an order of TAP106K035s. I've to decide only how many caps to replace (???).

 

[a.palfreyman]

All of them unless you want to play Russin roulette! You'll invariably end up having to do a similar process down the line so "do it once and do it properly' should be the motto.

 

[337alant]

I think that I can't put off a capacitors replacing and I'm going to place an order of TAP106K035s.

Ticking time bomb Luca, tants often fail short and could take out an IC
Alan

 

[337alant]

You can just replace all the tants in the power and control circuits with a low leakage electrolytic such as Nichicon FL.

Alan

 

[Pete MB&D]

Sounds like you have a dry joint on one of the regs if it came on while you where touching the heatsinks.

Pete

 

[Luca]

All of them unless you want to play Russin roulette! You'll invariably end up having to do a similar process down the line so "do it once and do it properly' should be the motto.

I am aware and agree that a full service, replacing all the tants and electrolitics at once, would be the best way to go.

Ticking time bomb Luca, tants often fail short and could take out an IC
Alan

Alan, you have made me remember what Jez said me when I showed my Teddy reg. clones stuffed of bead tants. I'll consider electrolytics for the replacement. Thanks!

Sounds like you have a dry joint on one of the regs if it came on while you where touching the heatsinks.

Pete

This fact happened twice. It may be not casual.
I will remember to check the quality of the welds. Thanks for pointing this out to me.

 

[Luca]

I will be very busy on the weekends in September with all the DIY works I have in progress and the cd player service is in queue.