shelf oscilating psu - diyAudio
Go Back   Home > Forums > Amplifiers > Power Supplies

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 25th July 2011, 03:45 PM   #1
diyAudio Member
 
east electronics's Avatar
 
Join Date: Jan 2006
Location: Athens GREECE
Default shelf oscilating psu

simple as that ...

just seen the revox B251 power supply unit .... i may also post a schematic

that is actually a simple oscilator and more actually the circuit that was was used as an "inverter" inside the first "economic" lamp SL 18- SL25 from philips ( if memory serves properly )

only adopted to higher power ..

any comments about this circuit ? it doesnt feature none of super functions like PWM or PFC but still worked quiet well ...for long time ..

Question is asked since "we" normally power amplifiers ... not spaceships
Attached Images
File Type: jpg b251 psu.JPG (136.3 KB, 324 views)
__________________
SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr

Last edited by east electronics; 25th July 2011 at 03:47 PM.
  Reply With Quote
Old 25th July 2011, 03:53 PM   #2
diyAudio Member
 
east electronics's Avatar
 
Join Date: Jan 2006
Location: Athens GREECE
or it could be the other way arround

what could possibly go wrong when a circuit like that is used next to a high tech supply ?

i see no regulation and that i can live with .... anything else ???
__________________
SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr
  Reply With Quote
Old 25th July 2011, 05:43 PM   #3
luka is offline luka  Slovenia
diyAudio Member
 
luka's Avatar
 
Join Date: Sep 2005
Location: in Slovenia :)
Send a message via Skype™ to luka
If the oscilator part is not to complex to make, I don't see nothing too bad about it. So what if it doesn't have regulation, really depends on application you need it for... But this days, IC are so cheap, I think I would still go with it, instead of only parts you see on schematic
__________________
home page @ http://www.classdaudio.tk/ @ 24/7 all year long
I FEEL SLOVENIA
  Reply With Quote
Old 28th July 2011, 09:27 PM   #4
sesebe is offline sesebe  Romania
diyAudio Member
 
Join Date: Jan 2011
Location: Iasi
If I'm right this power supply have some advantage. It is a resonant one, ZVS type, the current is sinusoidal and the harmonics are very low, so less noise to the amplifier.
A SMPS with IC need to be a resonant one to have the same shape of current and is not so easy to made.
  Reply With Quote
Old 28th July 2011, 09:40 PM   #5
diyAudio Member
 
east electronics's Avatar
 
Join Date: Jan 2006
Location: Athens GREECE
i have seen this type of psu made before but failed all the time i think poor choise of transistors or make of transformer ... but since im going to repair the revox i might take alook to see if its possible to get some expirience from that .

i will post my results here ...

regards sakis
__________________
SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr
  Reply With Quote
Old 12th January 2012, 11:11 PM   #6
sesebe is offline sesebe  Romania
diyAudio Member
 
Join Date: Jan 2011
Location: Iasi
Hello,

Any news with this power supply?
  Reply With Quote
Old 13th January 2012, 12:39 AM   #7
ontoaba is offline ontoaba  Indonesia
diyAudio Member
 
ontoaba's Avatar
 
Join Date: Nov 2009
Location: Kudus, Malang, Dieng
Hi, sakis.
For high power use, that self oscillating will need much bigger transistors to make it not breaking down at repetitive starting operating mechanism. While controlled switching PSU need much smaller switching transistors.
This transistor size differences will affecting many of its performance, efficiency, speed, and cost, so there are few people using that type of self oscillation in high power.
  Reply With Quote
Old 13th January 2012, 03:07 PM   #8
diyAudio Member
 
Join Date: Oct 2011
Location: Tauberbischofsheim, Germany
Quote:
Originally Posted by sakis View Post
that is actually a simple oscilator and more actually the circuit that was was used as an "inverter" inside the first "economic" lamp SL 18- SL25 from philips ( if memory serves properly )
Hi Sakis,

those pioneering Philips energy saving lamps didn't feature any electronics at all, they simply were miniaturized switch-start fluorescent lamps with in-built chokes, which made them so heavy (about 1 pound).

Modern economic lamps feature inverters comparable to your schematic.

Best regards!
  Reply With Quote
Old 13th January 2012, 06:23 PM   #9
jitter is offline jitter  Netherlands
diyAudio Member
 
jitter's Avatar
 
Join Date: Aug 2004
Location: Eindhoven, The Netherlands
Indeed, those first generation energy saving lamps had magnetic ballasts. They earned the nickname "jam jar" in Holland.

The circuitboard in the attached picture does show similarities to the left part of Sakis' schematic.

The pic, BTW, is of an end of life CFL from a well known Dutch department store, but it's acually a Philips Genie CFL.
Attached Images
File Type: jpg Dscn1783_small.jpg (202.7 KB, 158 views)

Last edited by jitter; 13th January 2012 at 06:33 PM.
  Reply With Quote
Old 22nd November 2012, 01:57 AM   #10
diyAudio Member
 
Steerpike's Avatar
 
Join Date: Jan 2006
Location: Johannesburg, South Africa
Old thread, but interesting. Also interesting: Revox abandoned this switching supply and went back to a conventional one (with 4x22,000uF capacitors!) in the B251's successor, the B250.
__________________
Steerpike's Toybox
  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
How to create self oscilating SMPS luka Power Supplies 10 7th January 2007 07:41 PM
Aleph P oscilating or something else!!! bbakota2000 Pass Labs 4 30th August 2004 05:17 PM
Looking for self oscilating class D lumanauw Class D 14 2nd March 2004 04:14 PM
And what about those shelf systems? r_s_dhar Everything Else 2 1st December 2003 11:18 PM
oscilating in capacitive load borisov57 Solid State 3 24th January 2003 01:29 PM


New To Site? Need Help?

All times are GMT. The time now is 01:37 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