Restore a Marantz 2275 for me - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 29th August 2008, 04:40 PM   #1
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
Default Restore a Marantz 2275 for me

Hi, I live in Australia and would be welcome to some helpful advice on where I could get components for such an old beast.

I'm considering restoring a pretty good condition Marantz 2275, I've heard it play and it sounds just fine, except for every now and again it generates some crackling, no doubt one of the many components which have reached and exceeded their useful life expectancy...

So I've decided to start a list of components to purchase, first off is capacitors, But I've already hit a snag, the two main filtering capacitors, both rated at 13,000uF at 55 volts with package dimensions of 51mm W x 70mm H.

They don't exactly have a modern counterpart, closest i can find is a 15,000 uF, so its clearly different to what I've got available today.

My first question in regards to the replacement capacitor is, is it a close enough drop-in component or will the rectifier be overly stressed enough to warrant upgrading? a Toshiba 6C3.

Also will voltage drop significantly or is there no trouble in this reguards?

In addition to that, is there anything else I should be concerned about, I'm not exactly an electronics expert, I'm just starting out infact, this is my first real restoration project..

The main goal of this restoration project is to bring it up to at-least working condition and maybe towards modern specifications, without too much loss in the original tonal quality, however no doubt a lot of the resistors will be in terrible condition, swaying out of value, so that will be the next step..

By the way, a schematic/service manual scan would be greatly appreciated.

Thanks in advance.
  Reply With Quote
Old 30th October 2012, 10:51 PM   #2
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
just resoldered the LHS amp board, going to try it out to see if it (the output transistors) still work.

When I pulled it out of storage the left hand channel was completely gone.

EDIT: Eureka!, I now have audio from the left channel, however it is distorted when the volume control is turned up and it is at a very low level, nothing like the right hand channel which is loud and undistorted.

Last edited by freax; 30th October 2012 at 11:17 PM.
  Reply With Quote
Old 30th October 2012, 10:59 PM   #3
diyAudio Member
 
Join Date: Jan 2011
Location: Fosser, Aurskog-Holand, Akershus, Norway.
The filter caps have typically a tolerance of -20% to +50%

This means that a capacitor labelled 13000uF may have an actual value between 10000uF and 20000uF.

So feel free to put in any cap you can find place for within lets say 63V rating.
(55V caps are rare) If a 30000uF (therytically) Cap fits mecanically, Its just fine.
Give You some more powerreserve in the bass region.

Please appology my poor English, I'm just a Norwegian
__________________
Sooner or later you end up with TANDBERG
  Reply With Quote
Old 30th October 2012, 11:03 PM   #4
DUG is offline DUG  Canada
diyAudio Member
 
Join Date: Jan 2003
Location: mississauga ontario canada
This might help:
http://akdatabase.org/AKview/albums/...e%20Manual.pdf

http://akdatabase.org/AKview/albums/...0schematic.PDF
__________________
Doug We are all learning...we can all help
"You can't stop the signal, Mal. Everything goes somewhere..."
  Reply With Quote
Old 30th October 2012, 11:25 PM   #5
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
Thanks for the help gents, after some google searching I have discovered these links:
Electrolytic Capacitor Shoot-Out - AudioKarma.org Home Audio Stereo Discussion Forums

Marantz 2275 Restoration - 1974 - Overclockers Australia Forums

I have a Ortofon Super OM 10 Stylus on its way to go with my Technics SL-1300 that I've just recently fixed by resoldering every soldered contact inside and a MJ vinyl arriving soon too.

Would be nice if someone could release a bias psu kit to go with my Matsushita EPC-451c (Got it for free out of a discarded turntable) cartridge too but alas I'll have to wait until I can build one myself from scratch.

Which has sparked off the need for a vinyl preamp or an amplifier which can support a turntable...

Hmm this looks interesting: http://forums.overclockers.com.au/sh...9&postcount=33

Panasonic THA series 15,000uF 80v caps

I might put an order in for some more capacitors aswell.

Last edited by freax; 30th October 2012 at 11:32 PM.
  Reply With Quote
Old 30th October 2012, 11:47 PM   #6
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
http://i.imgur.com/ucB7C.jpg
http://i.imgur.com/3UKKe.jpg

A bit rusty atop of that transformer, will have to wait.
  Reply With Quote
Old 31st October 2012, 01:39 AM   #7
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
Just incase oc.com.au change their forum site/software whathaveyou I've copied the parts list from there to here:
# Quantity P.no.
1 2 P10247-ND CAP 470UF 16V ELECT FC RADIAL 0 0.47000 $0.94
2 2 P11258-ND CAP 330UF 50V ELECT FC RADIAL 0 1.30000 $2.60
3 2 P10347-ND CAP 220UF 63V ELECT FC RADIAL 0 0.90000 $1.80
4 2 P11183-ND CAP 220UF 10V ELECT FC RADIAL 0 0.39000 $0.78
5 2 P10323-ND CAP 100UF 50V ELECT FC RADIAL 0 0.44000 $0.88
6 6 P11196-ND CAP 47UF 16V ELECT FC RADIAL 0 0.34000 $2.04
7 2 P11230-ND CAP 22UF 35V ELECT FC RADIAL 0 0.34000 $0.68
8 12 P11250-ND CAP 10UF 50V ELECT FC RADIAL 0 0.18800 $2.26
9 2 P13197-ND CAP 15000UF 80V ELECT THA 0 23.93000 $47.86
10 1 Z2633-ND RELAY PWR DPDT 5A 24VDC 0 7.26000 $7.26
11 22 P11212-ND CAP 10UF 25V ELECT FC RADIAL 0 0.12500 $2.75
12 2 PF2105-ND CAP 1.0UF 250V METAL POLYPRO 0 0.79000 $1.58
13 26 P10312-ND CAP 1UF 50V ELECT FC RADIAL 0 0.13700 $3.56
14 2 P10294-ND CAP 100UF 35V ELECT FC RADIAL 0 0.38000 $0.76
15 2 P10271-ND CAP 220UF 25V ELECT FC RADIAL 0 0.38000 $0.76
16 2 P11199-ND CAP 220UF 16V ELECT FC RADIAL 0 0.48000 $0.96
17 4 P10290-ND CAP 33UF 35V ELECT FC RADIAL 0 0.34000 $1.36
18 12 P11213-ND CAP 22UF 25V ELECT FC RADIAL 0 0.13700 $1.64
19 16 P10315-ND CAP 4.7UF 50V ELECT FC RADIAL 0 0.13700 $2.19
20 12 P10269-ND CAP 100UF 25V ELECT FC RADIAL 0 0.15300 $1.84
21 2 P11181-ND CAP 100UF 10V ELECT FC RADIAL 0 0.34000 $0.68
22 10 P4540-ND CAP .22UF 63V STACK METAL FILM 0 0.13300 $1.33
23 10 P4671-ND CAP .47UF 50V STACK METAL FILM 0 0.18200 $1.82
24 4 P5560-ND CAP .22UF 50V ELECT NHG RADIAL 0 0.24000 $0.96
25 2 P10296-ND CAP 220UF 35V ELECT FC RADIAL 0 0.48000 $0.96
26 2 P10776-ND CAP 100UF 100V ELECT FC RADIAL 0 1.01000 $2.02
27 10 P10314-ND CAP 3.3UF 50V ELECT FC RADIAL 0 0.13700 $1.37
28 10 P1175-ND CAP ELECT 4.7UF 25V SU BI-POLAR 0 0.15300 $1.53
29 2 P1195-ND CAP ELECT .47UF 50V SU BI-POLAR 0 0.24000 $0.48
30 5 478-1890-ND CAP TANTALUM 3.3UF 35V 10% RAD 0 0.65000 $3.25
31 5 478-1834-ND CAP TANTALUM 1UF 25V 10% RAD 0 0.46000 $2.30

NOTE: These are digikey.com parts numbers and you will need to use the .au digikey site (http://www.digikey.com.au/?curr=AUD) if you are ordering from AU, and pay $34 for shipping, so might aswell save up about $180 and buy them all at once.

ty, aokman for the hard work!

Last edited by freax; 31st October 2012 at 01:42 AM.
  Reply With Quote
Old 31st October 2012, 03:43 AM   #8
DUG is offline DUG  Canada
diyAudio Member
 
Join Date: Jan 2003
Location: mississauga ontario canada
"A bit rusty atop of that transformer, will have to wait."

soft cloth and some oil
__________________
Doug We are all learning...we can all help
"You can't stop the signal, Mal. Everything goes somewhere..."
  Reply With Quote
Old 31st October 2012, 05:31 AM   #9
diyAudio Member
 
Join Date: Apr 2010
Do not buy 0.47uF bipolar electrolytics. Instead replace with the cheapest 470nF polyester caps you can find.

Your weak channel sounds like a loose wire somewhere. Happens a lot when working in these old pieces.
  Reply With Quote
Old 2nd November 2012, 12:56 AM   #10
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
Quote:
Originally Posted by Coconuts 500 View Post
Do not buy 0.47uF bipolar electrolytics. Instead replace with the cheapest 470nF polyester caps you can find.

Your weak channel sounds like a loose wire somewhere. Happens a lot when working in these old pieces.
roger, thanks for that, I'm redoing all of the solder joints on the tone board today... waiting for my deoxit to arrive.
__________________
"It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away" - Antoine de Saint Exupéry

Last edited by freax; 2nd November 2012 at 01:07 AM.
  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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Marantz 510m Restore Photos GUROL Solid State 51 2nd September 2011 01:19 AM
Mcintosh MA 2275 burbeck Tubes / Valves 2 24th April 2009 11:00 AM
Restore muting on Marantz CD85 after NOS mod (Help!) Orion1 Digital Source 3 3rd December 2006 04:50 PM
Marantz 2275 - trouble in mono billinchile Solid State 1 23rd April 2004 06:33 PM


New To Site? Need Help?

All times are GMT. The time now is 07:43 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