Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Keantoken's CFP cap multiplier
Keantoken's CFP cap multiplier
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 22nd November 2015, 12:57 PM   #891
rensli is offline rensli  Estonia
diyAudio Member
 
Join Date: Jul 2014
Some fotos:

Filter capacitors are all the same brands in LM and k-mult filter-bank.
All samwha-s, dirty cheap. Capacitance amount is also the same 2200uf + 2x 470uF.

Sound still so different
Attached Images
File Type: jpg 221120151729.jpg (845.5 KB, 520 views)
File Type: jpg 221120151730.jpg (666.0 KB, 494 views)
File Type: jpg 221120151731.jpg (575.2 KB, 461 views)

Last edited by rensli; 22nd November 2015 at 01:02 PM.
  Reply With Quote
Old 22nd December 2015, 02:20 PM   #892
Krissz80 is offline Krissz80  Hungary
diyAudio Member
 
Join Date: Dec 2015
Hi all!

I'm new here, and I have a problem with K-multi (positive version).
I've built the K-multi width BD140-16 and 1 piece of 1N4148 diode.
And I've put in the LED in opposite direction (but theoretically it should not make any difference).

In addition I use a 10nF X7R between the B-E leg of the BC337, and I use one 100nF X7R parallel to each elektrolite capacitor.

The input is voltage came from a stabilizator circuit width LM1084.
This is it's output characteristic measured by Scope.
The output is 12v 1,2A (load resistance was 10 ohm 20W).
After I connected the K-multi to the stabilizator circuit I got the following result measured by Scope.

Can anybody tell me why is it have 25MHz sinus noise on it.
  Reply With Quote
Old 19th February 2016, 10:09 AM   #893
av-trouvaille is offline av-trouvaille  Netherlands
diyAudio Member
 
Join Date: Aug 2003
Location: Near Rotterdam
It seems up to now, the K-multiplier presupposes a power supply with C-filter to smooth the DC input voltage (so an elco of significant capacitance after the bridge rectifier). In terms of function a K-multiplier might be seen as a substitute for a choke. So, the K-multiplier as an electronic choke. Would it be allowed to use a K-multiplier as a choke-input filter? That is, a K-multiplier right after the diode bridge, and the smoothing C after the K-multiplier?
I only ask whether it is technically allowed, not if it would be the optimal place.
  Reply With Quote
Old 19th February 2016, 05:33 PM   #894
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
A large inductor right after the rectifiers can see extreme ripple and negative voltage at the input. This is far beyond the scope of the KM. There must be at least enough capacitance at the input to bring ripple down to it's working range.
__________________
The Kmultiplier rail filter! -=- The Simple Kuartlotron Superbuffer!
Need something built, repaired or modded? PM me and ask what I can do!
  Reply With Quote
Old 19th February 2016, 06:19 PM   #895
av-trouvaille is offline av-trouvaille  Netherlands
diyAudio Member
 
Join Date: Aug 2003
Location: Near Rotterdam
Yes, I am aware that a large inductor right after the rectifiers can see extreme ripple and negative voltage at the input. I notice that in the choke input filters for my tube amps. But its peak would diminish fast as soon as current is drawn. Is it an option to simply add a zener of appropriate voltage between the rectifier and the K-multiplier to tame the peak?
  Reply With Quote
Old 19th February 2016, 06:26 PM   #896
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
Quote:
Originally Posted by Krissz80 View Post
Hi all!

I'm new here, and I have a problem with K-multi (positive version).
I've built the K-multi width BD140-16 and 1 piece of 1N4148 diode.
And I've put in the LED in opposite direction (but theoretically it should not make any difference).

In addition I use a 10nF X7R between the B-E leg of the BC337, and I use one 100nF X7R parallel to each elektrolite capacitor.

The input is voltage came from a stabilizator circuit width LM1084.
This is it's output characteristic measured by Scope.
The output is 12v 1,2A (load resistance was 10 ohm 20W).
After I connected the K-multi to the stabilizator circuit I got the following result measured by Scope.

Can anybody tell me why is it have 25MHz sinus noise on it.
Sorry I missed this. Can you tell me why you made those changes? If anything the 10nF cap should go on the B-E of the BD140. And I think I have seen more than one KM using the BD140 that oscillated.

The KM should have capacitors close to both the input and output, but 100nF film caps are unnecessary and sometimes will even cause oscillation.
__________________
The Kmultiplier rail filter! -=- The Simple Kuartlotron Superbuffer!
Need something built, repaired or modded? PM me and ask what I can do!
  Reply With Quote
Old 19th February 2016, 06:32 PM   #897
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
Quote:
Originally Posted by av-trouvaille View Post
Yes, I am aware that a large inductor right after the rectifiers can see extreme ripple and negative voltage at the input. I notice that in the choke input filters for my tube amps. But its peak would diminish fast as soon as current is drawn. Is it an option to simply add a zener of appropriate voltage between the rectifier and the K-multiplier to tame the peak?
The KM would have to turn on and off to charge the reservoirs, and a zener does not store power and so cannot support the input voltage of the KM when input is low. A zener to reduce the positive peaks would either short the rectifier or it would go across the KM, effectively bypassing it and ruining the goal of filtering.
__________________
The Kmultiplier rail filter! -=- The Simple Kuartlotron Superbuffer!
Need something built, repaired or modded? PM me and ask what I can do!
  Reply With Quote
Old 19th February 2016, 07:56 PM   #898
av-trouvaille is offline av-trouvaille  Netherlands
diyAudio Member
 
Join Date: Aug 2003
Location: Near Rotterdam
Thanks for clarifing. No choke input with the K-multiplier for me, then.
  Reply With Quote
Old 21st February 2016, 12:44 PM   #899
av-trouvaille is offline av-trouvaille  Netherlands
diyAudio Member
 
Join Date: Aug 2003
Location: Near Rotterdam
Another question to explore the versatility of the K-multiplier, when allowed.
The current capability of the K-multiplier is limited to about 1A. Earlier you mentioned it is hard to design for more current.
Would it be feasable to increase the current capability by putting two K-multipliers in parallel?
  Reply With Quote
Old 21st February 2016, 01:13 PM   #900
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
The power can be increased by using parallel degenerated transistors. However you can overload the driver.
__________________
The Kmultiplier rail filter! -=- The Simple Kuartlotron Superbuffer!
Need something built, repaired or modded? PM me and ask what I can do!
  Reply With Quote

Reply


Keantoken's CFP cap multiplierHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Vbe multiplier - bypass cap Donk Solid State 7 22nd January 2008 01:55 AM
Question(s) about CFP. Justcallmedad Solid State 94 20th September 2005 10:08 AM
cap multiplier or not? PederBass Solid State 13 23rd March 2004 06:26 PM
Cap. multiplier or regulated supply ? Buhl Pass Labs 1 8th October 2003 10:51 PM


New To Site? Need Help?

All times are GMT. The time now is 07:09 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki