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 24th November 2010, 01:14 AM   #141
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
A jfet current source will improve specs dramatically.

- keantoken
Attached Images
File Type: png Kmult10A_CCS.png (87.2 KB, 722 views)
__________________
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 24th November 2010, 06:06 PM   #142
Joshua_G is offline Joshua_G  Israel
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by keantoken View Post
A jfet current source will improve specs dramatically.

- keantoken
1. The circuit diagram is unreadable.
2. There is no indication what the different colors mean.
3. The JFET current source isn't drawn in the diagram, only general current source is drawn.
  Reply With Quote
Old 24th November 2010, 09:06 PM   #143
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
The color scheme is no different than the last image. If you can't read it, hover the mouse and you will see a zoom button in the lower left.

Perfect or not, some sort of current source will improve performance. That was the point I intended to make.

- keantoken
__________________
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 24th November 2010, 09:14 PM   #144
Joshua_G is offline Joshua_G  Israel
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by keantoken View Post
The color scheme is no different than the last image. If you can't read it, hover the mouse and you will see a zoom button in the lower left.

Perfect or not, some sort of current source will improve performance. That was the point I intended to make.

- keantoken
There is a possible difference between "some sort of current source" and a detailed, specific current source. Either you are into simulation exercises, or you present a circuit that others can build.
  Reply With Quote
Old 24th November 2010, 09:57 PM   #145
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
I never told anyone to build that circuit. Be patient if you will, I'm not done!

Firstly, all of these circuits are hardly stable. If you built them in real life, they would go insane. Right now I'm determining how best to stabilize them.

- keantoken
__________________
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 24th November 2010, 11:08 PM   #146
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
Okay, the pictures are crappy. It doesn't matter much, because they're not final either. Sorry to be short, but if you can't read the picture, don't try building it. I'm just trying to spark some helpful conversation.

I'm switching gears to the 300mA version again. I was conservative with the original design, but as it turns out, being conservative has bit me in the **** every time. The single best thing you can do to increase performance is to increase the current through the driver transistor. This increases the transistor's transconductance, which the slave's impedance is divided by to produce the final output impedance value. I put the maximum at 20mA, as this is as far as most good small-signal TO92's go that still have good Ft. Decrease to 15mA, considering the Ib of the outputs.

A Jfet should decrease noise, but I don't know much about that. In any case we need a Jfet with low noise and high Idss (20mA max), and tempco is not important.

BTW, my 2SC5171 and A1930 models are VERY broken, I wish I had seen this earlier. I've substituted different models.

Schematic and Zout plots at 300mA. There is actually little difference between the resistor and Jfet. I think this is because at such low currents, there is little voltage variation across the resistor.

- keantoken
Attached Images
File Type: png Kmult_47R_Jfet_Schem.png (101.0 KB, 735 views)
File Type: png Kmult_47R_Jfet_Zout.png (55.1 KB, 689 views)
__________________
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 25th November 2010, 12:29 AM   #147
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
I believe both versions will work, and I built the resistor version which was stabilized with electrolytic bypass (NOT film, but I want to make it stable with films).

- keantoken
__________________
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 25th November 2010, 12:54 AM   #148
Joshua_G is offline Joshua_G  Israel
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by keantoken View Post
I never told anyone to build that circuit. Be patient if you will, I'm not done!

Firstly, all of these circuits are hardly stable. If you built them in real life, they would go insane. Right now I'm determining how best to stabilize them.

- keantoken
This is a DIY forum. Why wouldn't you publish a schematic only after finishing playing with simulations and actually building one?
  Reply With Quote
Old 25th November 2010, 01:41 AM   #149
MJL21193 is offline MJL21193  Canada
Account disabled at member's request
 
MJL21193's Avatar
 
Join Date: Mar 2007
Quote:
Originally Posted by Joshua_G View Post
This is a DIY forum. Why ....?
Here is a good question: What is your problem?
Strive to answer that and then come back and see if you can make a relevant contribution instead of constantly picking fights.
  Reply With Quote
Old 25th November 2010, 02:07 AM   #150
keantoken is offline keantoken  United States
diyAudio Member
 
keantoken's Avatar
 
Join Date: Aug 2006
Location: Texas
Here Joshua, I built it, and it works EXCEPTIONALLY WELL!

56db input isolation, which was better than last time (tested at about 200mA). Input ripples are 63mV, output are 100uV. Noise is >10uV as far as I can tell.

Josh has a point, but despite that others here don't mind me posting untested schematics just to see what I've been doing as of late. This forum is a casual place, so if you want a scrupulous design team you'd better say so from the beginning, before the mood of the thread is set.

I have to extend great thanks to HiFi as he spent his own money to get me the parts this reg was made from.

So the question is, why were HiFi's results not as good?

- keantoken
Attached Images
File Type: jpg DCP00890.JPG (361.1 KB, 620 views)
__________________
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 02:55 AM
Question(s) about CFP. Justcallmedad Solid State 94 20th September 2005 11:08 AM
cap multiplier or not? PederBass Solid State 13 23rd March 2004 07:26 PM
Cap. multiplier or regulated supply ? Buhl Pass Labs 1 8th October 2003 11:51 PM


New To Site? Need Help?

All times are GMT. The time now is 07:04 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki