CD63 display died, please help

[SimontY]

Hi everyone,

After performing further modifications to my player (16 resistors and 2 decoupling caps in analogue section) my display has stopped working.

I turn it on, it works, plays CDs (and sounds amazing!), but the display is dead. I had thought of adding a switch to turn this off before...but always off is not what I had in mind!!!

Has any CD53/63/67/etc. owner had experience in fixing a faulty/dead display?

(I remember reading on Thorsten's tweaks on tnt, he had a problem with his display after some modding, maybe I should e-mail him? (don't really want to just out of the blue though) )

----------------
Zombie,
if you are reading this, the resistor changes I made were (all) the 10k and 27k resistors. I used 1% metal film, and matched L+R to ~0.1% tolerance (best I could get with my DMM). (I also changed two decoupling caps to spare Elna Silmics, as tnt did)

The sound: incredible improvement! - everything is better: imaging, detail, smoothness/sweetness, control, huge drop in harshness/coldness/crap-cd-sound/white nastiness, much less over-hyped. Same or even greater magnitude than removing output caps, changing op-amps, or reclocking using a dedicated psu. This player is now probably as good as players like the Arcam FMJCD33 or Linn Genki. (maybe I will take it into the shop and compare!)


TIA,
-Simon

 

[Elso Kwak]

Dead Display

Hi SimontY,
Check the zener diode in the Display supply.

 

[SimontY]

Hi,

Check the zener diode in the Display supply

Elso,

Thanks for the suggestion, but I have no diode tester, is there another way to test it? If you have a good suspicion it's this I will buy one and change it anyway - I, ahem, *need* to order more caps for the player anyway...


-Simon

 

[hifi]

You dont even got a multimeter?...I say get one =)


/micke

 

[SimontY]

You dont even got a multimeter?...I say get one =)

I have a multimeter, it just doesn't happen to have a diode tester - bought the wrong one damn it

I also have an old 2nd hand 'scope in my possession right now, but I don't really know what to do with it -I just like to look at 60hz sine waves from a test disc, and watch the valves glow


-Simon

 

[hifi]

meassure the voltage across the zener, that should show you if it is working propperly

/micke

 

[SimontY]

meassure the voltage across the zener, that should show you if it is working propperly

I guess you mean whilst it's on, what am I looking for, just any reasonable voltage? (yes, I know it sounds stoopid...)


-Simon

 

[jean-paul]

The voltage that is written on the zenerdiode itself should be measured over it. It has 0.6 to 0.7 V in forward direction ( to be measured when power is off with a diodetester !!!! ) and the written voltage in reverse direction. For example a 6.8 V zenerdiode is used for creating a reference voltage of 6.8 V. The zener in your cdplayer will be about 22 to 30 V for creating a voltage for the display-tube. I suggest you google for the exact explanation of how zeners work and what purpose they are for.

To be honest I think when you lack the basic skills you better leave the repair and modifications to a more experienced person to avoid further damage. This is not meant as a negative remark but to save you from further costs. A small error can cause costly repairs or even a dead cdplayer

Basic skills and at least a decent multimeter are required for any job on electronic gear.

 

[hifi]

yes, Jean-Paul is right sorry for being so unprecise.


/micke

 

[SimontY]

Thanks guys,

leave the repair and modifications to a more experienced person to avoid further damage

Yes, but there is no-one! This is how I learn. I have performed many mods to the player, and as a result it sounds excellent. The player was worth little to me unmodified.

I have had to pay for repair once already, but £50 is nothing when the player sounds like £1000+. Make any sense? It does to me.

I will take the advice and learn some basics, I think an electronics course is on the cards...

Btw, I do know roughly what a zener diode is - voltage flows more easily in one direction than the other - I just don't know much more than the VERY basics - but I would know nothing if it wasn't for the desire to achieve real music from my system...and DIY audio


-Simon

 

[jean-paul]

I just don't know much more than the VERY basics - but I would know nothing if it wasn't for the desire to achieve real music from my system...and DIY audio

You have a point there and to be honest I started the same way too. Then I learnt the basics and errors became less and I actually started to understand what I was doing.

Continue with the mods but work tidy and thoruoghly think over what you want to do before doing it. This forum can be of great help when you're not sure what to do.

Please measure the display tubes voltage as I guess it doesn't function as it should.

 

[SimontY]

I started the same way too.

That's encouraging

-Simon

 

[jean-paul]

That's encouraging

And I burnt some cdplayers too

You can find the service manual here:

http://www.alw.audio.dsl.pipex.com/Downloads/CD43_53_63_Service_Manual.pdf

Check the voltage at Q581's output ( -24.4 V ) and between VF1 and VF2 ( 3.6 V ). Be careful not to short pins when you measure.
VF1 and VF2 have -19.5 V with repect to ground. If voltages are OK there is probably one of the transistors blown that switch on the display voltage like Q852 etc.

Mmm, my 1000st post ! Time for a

 

[SimontY]

You can find the service manual here:

Thanks for getting the link, but I got that (from a thread on here) already!

I was looking at it only 30 minutes ago

-Simon

 

[SimontY]

Just in case you're interested, here is a pic from yesterday, just before the display fault occured.

You can see the CAT5 lead, input cap, rearranged Elna caps, Audiocom DVC-1 clock and power input with black gate, changed output caps, ic shielding with blu-tac etc etc. Its so much fun, isn't it? (apart from when it goes wrong...)

Congratulations on your 1000th post!!!

I will hopefully check the thing tomorrow, I'm too tired now

 

[psarin]

moot point

Hi

In the process of fixing this problem, you may want to add a switch to manually turn off the display My Denon DCD-1560 cd player has a front panel button to do just that. Apparently turning off all the display LED's leads to a quieter playback circuit (since all the switching diodes are now off). I have seen a few other older high-end cd players that have the same facility.

Good luck with the solder iron!

Cheers -

Pradeep

 

[jean-paul]

CD63 doesn't have a multiplexing ( and terribly interfering ) LED display, it has a display tube.

Please study the schematic if nothing can blow while switching the display off and on. Better repair it first before adding a switch to switch it off again

IME there is a small difference when the display isn't lit but it can be darn impractical now and then

 

[SimontY]

So, 1.5 years has gone and I feel like trying to fix my cd player display again, lol

Today I actually removed the display/control board from it's plastic surroundings (the player's fascia). The display tube has a sort of stained, dark area in one corner - could it be burnt/broken?

I plucked up the courage to measure the voltage going in to the display/control umbelical socket - this was 5v as it's meant to be, so I've narrowed the problem down now.

Perhaps a photo of the display will help, I'll go and take one...

 

[SimontY]

Righto, can anyone who knows what these are meant to look like please tell me if it's supposed to have that cr@p in the corner?

 

[Ruach]

I may have the solution to your problem.

I had the same problem on my CD63 some years back when I was modding it.

In my situation, everything on the CD63 worked except the display.

After one day/nite of troubleshooting, I discovered that one of the copper threads supplying 5V to the microprocessor and data i/c has broken contact. A simple hardwiring fixed the problem.

You may have lifted the thread when you are installing a bigger capacitor at C815.

Hope this helps.