Marantz CD-50 and CD-60, TDA1541, CDM4/19

[Mayday]

Hi May-day.

Yep the TDA1549 is a v out dac, and I also tried it briefly with a 6N16 cathode follower, but the soundstage was much smaller and not as accurate.
It also lowered the output too much.

The sound might have more to do with the fact that there was two cheap film caps in the signal path, instead of just one now.

Tomorrow I might try it with a SRPP 6N16 stage with two Obbligato caps instead.
It should give higher output and better sound with the better caps.
And I already have the tube stages build.

I also used lots of Oscon's and they work well and are cheap too.

Regards
Kim

Hi.
I use alot of oscons too, mainly SEPC.
Also use Rubycon ZL, ZLH and ZA.
ELNA Silmic ROS and ELNA RJH.

How did you do the filter? opamps aren't just I/V and buffer, but filter too.
I'll use passive I/V(50R non-inductive resistor) and a 47nF cap across signal and singal-gnd will be filter.

I like that ECC86 can run of a 24VDC supply with 6VDC for heaters(or taken from 24VDC with a power resistor to lower voltage.).

 

[Kim Schultz]

Hi.
The TDA1549 does nearly all filtering needing only one feedback cap for a first order filter. It runs at 4 times over sampling.

Some say the filter cap can be removed without any issues, but I have not tried it yet.

Regards
Kim

 

[Mayday]

Thinking of putting together some small shunt regs for the TDA1541A since it's not as gready for current as the SAA7220. I have a +5VDC schematic, but none for the -5VDC and the -15VDC.

I'll also replace e-lytic's after opamps w 6,8uF MKP's. Did this in the CD-60 w good results, however the e-lytic in that case was bipolar nichicon muse. I think I can swap for MKP's regardless if output cap from opamp is bipolar or standard.

I haven't heard TDA1549, but I absolutely love the TDA1541A(IF it's given the proper circuit and components to match it).

 

[korben69]

Hi Mayday and others DIY'ers

I'm following your work with great interrest, nice "HowTo" for the CD50
I've got one aside ready for cooking, a CD40 too, but later...

I'm wondering about the attached pic posted in the thread, what Marantz CD is it ?
The PCB looks very close to my faulty CD873, Hedphone section not implemented (connectors/AOP).
I'm convinced it's the same PCB, except the fact that some options aren't plugged/populated.
Marantz CD873 is a "Midi' size player : CDM4/11 - TDA1541 - SAA7220...
I've to fix a tray trouble but can't find the Service manual for the board.
Player works fine but refuses to eject the CD when pushed.

Thank for your help

[End of threadJacking]

 

[Mayday]

Hi Mayday and others DIY'ers

I'm following your work with great interrest, nice "HowTo" for the CD50
I've got one aside ready for cooking, a CD40 too, but later...

I'm wondering about the attached pic posted in the thread, what Marantz CD is it ?
The PCB looks very close to my faulty CD873, Hedphone section not implemented (connectors/AOP).
I'm convinced it's the same PCB, except the fact that some options aren't plugged/populated.
Marantz CD873 is a "Midi' size player : CDM4/11 - TDA1541 - SAA7220...
I've to fix a tray trouble but can't find the Service manual for the board.
Player works fine but refuses to eject the CD when pushed.

Thank for your help

[End of threadJacking]

Thanks.
There are pics posted of Marantz CD-50, CD-60 and CD75dx. Some pics can't be seen now since I've exceeded the photobucket bandwith it seems.
The pic you attached looks like a mix between cd-50 and cd-75dx.

Tray trouble? Explain. Could be that it needs new cog and belt? Cleaning and re-greasing?

I don't mind you using this thread to ask about similar players.

 

[Mayday]

Got some work on the CD-74dx done today.
Swapped all PS caps and started swapping the others.

 

[korben69]

Thanks for your kind words Mayday.
It seems that the board is the CD74x.
Do you have the Service Manual or a link to download it ?
Anwerring to myself : http://fileshare.eshop.bg/
But no SM for CD74x...

The CD873 is fully functional except open tray operation.
"Eject button" has no effect, I have to open the tray to change the CD...
Motor try to eject the tray but stops and stay where it is, no more action.
When tray is open, I can move the tray in and out, but carring not to let it go to the end.
If so, the tray reaches the end of the player, the effect is that it can't be opened except manually.

I've checked belt and mechanism, i'ts Ok and works fine.
Any suggestion ?

 

[Mayday]

Thanks for your kind words Mayday.
It seems that the board is the CD74x.
Do you have the Service Manual or a link to download it ?
Anwerring to myself : Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
But no SM for CD74x...

The CD873 is fully functional except open tray operation.
"Eject button" has no effect, I have to open the tray to change the CD...
Motor try to eject the tray but stops and stay where it is, no more action.
When tray is open, I can move the tray in and out, but carring not to let it go to the end.
If so, the tray reaches the end of the player, the effect is that it can't be opened except manually.

I've checked belt and mechanism, i'ts Ok and works fine.
Any suggestion ?

The motor that drives the tray? Bad cap/caps in the motor PS?
I don't know. Try measure the voltage available for the motor.

Sorry, I only have the CD-50 SM

 

[Mayday]

Got some more of my new favorite tools:

Also got two of each, 7815, 7915, 7905.

 

[Mayday]

Got some more caps today.

CD-75dx
-5Vdc reg for TDA1541A (no shorts, though it looks that way in the pic)

-15Vdc reg for TDA1541A

+5Vdc reg for TDA1541A fitted. Stole DC from the same point I stole it to SAA7220 reg.

 

[korben69]

Hi Mayday

The motor that drives the tray works fine, as the belt and puley.
You're right I've to check tray caps in motor PS
It seems that the tray goes wrong when it came inside the mechanism.
When Eject button is pressed, it refuses to operate, it tries but stops immediatly...
Don't worry, I'll find... or not

Maybe UV101 could give me some hints, refering to my previous posted pic, CD873 board looks really really close (CD65SE).

Kim, nice to see you're modding a 1549 player. I've planned to perform it on CD751 and CD753 units, after fixing my CD873 trouble. I've got SM for both players...

 

[Kim Schultz]

eBay is our friend for cheap components.

I have also used nearly two rolls of solder wick after I started working on the old cdp's. Funny how they have been in the drawer the last couple of years, and then they are all used up in a couple do weeks.

I did some tests yesterday using a SRPP tube output stage. But even though I used the same caps as the direct out mod, and had the tube current where is usually sounds good, it was still not the same magic as the direct out.
It might need more burnin time though.

Unfortunately I can't get very much listening done, because the CDM12.1 laser is acting up, refusing to play more and more cd's. So now I have to wait for a new laser

May-day, looking good, I have thought about adding seperate regs for the chips too.

Korben69, I think you will be pleasantly surprised by the TDA1549, it sounds great.
I hope I can get the cdp fixed with a new laser.

Regards Kim

 

[Mayday]

Thanks.

I'm thinking I might need to solder a cap on the In pin of the regs since they are rather far from the PS? Just woke up from a nap, and I need atleast two more cups of coffee before my brain starts working. If I put a polarized cap ELNA RJA 180uF between In leg and PS wire, which way do I point it? Same way for pos and neg supply?

 

[Mayday]

I have also used nearly two rolls of solder wick after I started working on the old cdp's. Funny how they have been in the drawer the last couple of years, and then they are all used up in a couple do weeks.

I found that adding more flux(I have a flux pen that was very expensive but is very good) to the wick even if it has flux already makes a huge difference. I simply drag(?) (drar på svenska) the pen over the piece of wick I'm about to use.

 

[Mayday]

Thanks.

I'm thinking I might need to solder a cap on the In pin of the regs since they are rather far from the PS? Just woke up from a nap, and I need atleast two more cups of coffee before my brain starts working. If I put a polarized cap ELNA RJA 180uF between In leg and PS wire, which way do I point it? Same way for pos and neg supply?

Between Vin and gnd that is(told you I wasn't awake). And the direction of the caps is clear now that I realized that.

 

[korben69]

The motor that drives the tray? Bad cap/caps in the motor PS?
I don't know. Try measure the voltage available for the motor.

Voltage on the motor tray : -4.78V going inside & +4.79V moving outside.
I've to care the tray don't go completely inside, otherwise it's locked and I've to it push manually... searching on the 65DX SM some hints.

Nice caps

 

[Mayday]

ELNA RJH, not RJA. The caps I'm going to put Vin to gnd on the regs.

The oscon sepc are very nice too. But I don't see the benefit of using them here since there'll be a reg between the cap and the digital IC.

What are the voltage supposed to be for the motor? If a cap is bad in the PS it might loose power and not be able to completely move the tray?

 

[korben69]

I've read the SM and it should be 5.00V, maybe 4.78V is a too low value.
I'll check tomorrow, time to sleep.
Thank you Mayday
Cheers

 

[Mayday]

I've read the SM and it should be 5.00V, maybe 4.78V is a too low value.
I'll check tomorrow, time to sleep.
Thank you Mayday
Cheers

Doubt that would be too low on its own. Don't remember if you had cleaned and lubricated the sled(where it should be greased, and only use very little).

I'd check caps and also maybe clean what looks to be switches in the Schematic you posted.

 

[Mayday]

Done with the -5V and -15V regs.