Marantz CD63 & CD67 mods list - Page 38 - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 19th January 2006, 12:22 PM   #371
6h5c is offline 6h5c  Netherlands
One Seriously Addicted to Audio and Electronics
diyAudio Member
 
6h5c's Avatar
 
Join Date: Apr 2004
Location: Heerhugowaard
Well, here's yesterday's homework: I've added a calculation for the new transformer in my spreadsheet.
The first four windings are required for the player, and i've added three 9,5V/150mA windings for 5V purposes. This will allow even the use of two stage regulators if i'm not mistaken.
The 9,5V nicely corresponds with the already required 9,5V for the player, and i've made the +/-12V windings twice that voltage. It will make the manufacturing easier/cheaper I hope.

I upped the required currents considerably, and still haven't reached 30VA, so there's room for some more, but I doubt if it is needed. But this is just a first attempt, what do you guys think?

Regards,

Ray.
Attached Files
File Type: pdf cd63_67_voltages.pdf (43.9 KB, 196 views)
__________________
Gonna buy my little girl a pink soldering-iron
The new DOS-CFP board is out!
  Reply With Quote
Old 19th January 2006, 12:28 PM   #372
poynton is offline poynton  United Kingdom
diyAudio Member
 
poynton's Avatar
 
Join Date: Mar 2005
Location: A life on the ocean waves when I'm not at home in N. Wales (but I'm not Welsh so no sheep jokes!)
Looks fine to me.

Andy
  Reply With Quote
Old 19th January 2006, 12:31 PM   #373
diyAudio Member
 
Fidelity Audio's Avatar
 
Join Date: Dec 2005
Location: Doncaster England
yep thats good
  Reply With Quote
Old 19th January 2006, 05:28 PM   #374
diyAudio Member
 
Michi124's Avatar
 
Join Date: Dec 2003
Location: Berlin, Germany
Thanks for that homework, Ray

One suggestion:
Since Vf and Vftd use up 165 and 26mA respectively,
I think they should get a little more overhead - what about 300 and 75mA?

To get to 30VA, I raised the other current ratings as well:

+/-12V 2x19V 2x200mA
+/-10Y or +5V 2x9V 2x750mA
Vf display 3,4V 300mA
Vftd display 14V 75mA
Ext. clock+DAC 9,5V 200mA
DAC D 9,5V 200mA
DAC A 9,5V 200mA

This adds up to 29,62VA

Quote:
Originally posted by poynton
what is the minimum order, price, lead time etc??
Is ofc possible? Copper screen?
I have no idea.
As soon as we agree on a winding scheme, I can ask for quotes.

Yes, I would also want this custom trannie to be better than the KI one...
__________________
Brutalized by bass
and terrorized by treble...
  Reply With Quote
Old 19th January 2006, 08:49 PM   #375
6h5c is offline 6h5c  Netherlands
One Seriously Addicted to Audio and Electronics
diyAudio Member
 
6h5c's Avatar
 
Join Date: Apr 2004
Location: Heerhugowaard
Hi Michael,

The main reason I didn't give the display more overhead is because the heater voltage is critical. If you give this winding a higher current, the voltage will become higher because you only draw 165mA. Since it is not regulated, the display will not like that. It's like the heater voltage with tubes. At this low voltage, a small increase can lead to a lot of extra current (the heaters are low-ohmic).

The manufacturer will wind the transformer assuming that when all windings draw their maximum current, the voltages should be as stated. Since that is not likely to happen here, all voltages will be a bit higher already.

I think 200mA is more than enough for the heaters, and 50mA will be fine for the negative display voltage.
The other voltages are all regulated, so 200mA is perfect.

Except for the +/-10V for the CD63.
I would keep that one 9,5V because it is also unregulated. The current for this one is too high, remember that all the stuff that now hangs on the +5V rail is going to be powered by the other windings.

You don't have to reach 30VA, it's not bad to have a 25VA tranny on a 30VA core
It will leave some room for a ground shield and plenty of isolation, since we have a lot of windings on the core.

Regards,

Ray.
Attached Files
File Type: pdf cd63_67_voltages.pdf (43.9 KB, 117 views)
__________________
Gonna buy my little girl a pink soldering-iron
The new DOS-CFP board is out!
  Reply With Quote
Old 19th January 2006, 09:39 PM   #376
diyAudio Member
 
Michi124's Avatar
 
Join Date: Dec 2003
Location: Berlin, Germany
Thanks for pointing that out, Ray.
My knowledge of this is *ahem* rather limited, sorry...
__________________
Brutalized by bass
and terrorized by treble...
  Reply With Quote
Old 19th January 2006, 11:37 PM   #377
diyAudio Member
 
Fidelity Audio's Avatar
 
Join Date: Dec 2005
Location: Doncaster England
nice one ray
  Reply With Quote
Old 20th January 2006, 09:32 AM   #378
6h5c is offline 6h5c  Netherlands
One Seriously Addicted to Audio and Electronics
diyAudio Member
 
6h5c's Avatar
 
Join Date: Apr 2004
Location: Heerhugowaard
Quote:
Originally posted by Michi124
Thanks for pointing that out, Ray.
My knowledge of this is *ahem* rather limited, sorry...
No problem. The drawback of more knowledge is that I have to be careful I don't overdo all this 'engineering' thinking in simple situations that don't require it
I guess the +/10V winding current can be scaled up a bit after all, since the TCA drivers can handle up to 40V! (missed that one...)

With all the voltages covered, i'm very curious about that quote you mentioned!

Regards,

Ray.
__________________
Gonna buy my little girl a pink soldering-iron
The new DOS-CFP board is out!
  Reply With Quote
Old 20th January 2006, 09:54 AM   #379
diyAudio Member
 
Fidelity Audio's Avatar
 
Join Date: Dec 2005
Location: Doncaster England
Now then Ray you mention scaleing up the voltage on the 9.6v winding (cd63) because the TCA can handle up to 40V.
Now the 5v rail also comes from this winding via bridge and reg.

A standard reg can handle a maximum input of 35V and the Audiocom regs (which I use) have a maximum voltage input of 24V.

So a maximum voltage of 14V would be needed so that the TX is a straight swap into a standard player. This should after rectification give approx. 20V.

Hope I made sense. lol
  Reply With Quote
Old 20th January 2006, 10:03 AM   #380
6h5c is offline 6h5c  Netherlands
One Seriously Addicted to Audio and Electronics
diyAudio Member
 
6h5c's Avatar
 
Join Date: Apr 2004
Location: Heerhugowaard
Hi Brent,

Don't worry, it says scaling up the CURRENT
The voltage will only be a little bit higher because of that, and I was just wondering how much the drivers can handle, since the voltage is unregulated.

But you make sense if it would be the voltage

Ray.
__________________
Gonna buy my little girl a pink soldering-iron
The new DOS-CFP board is out!
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 09:08 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2