Quasi ~ Quasi
Four Output Device QuasiComp PCB without DC detect
Check 200 Ohm pot for orientation! The PCB image should be correct.
There are different board images after Q tweaked his layout. I think the master changed a few other traces when he did his tweak. This image is based off of the original set with a small change for 200 R potentiometer.
Shawn.
quasi said:
Four Output Device QuasiComp PCB without DC detect
Check 200 Ohm pot for orientation! The PCB image should be correct.
There are different board images after Q tweaked his layout. I think the master changed a few other traces when he did his tweak. This image is based off of the original set with a small change for 200 R potentiometer.Shawn.
Hi Shawn,
I have a few, but not many. You probably were shown the 2SA970 and 2SC2240 trays. What you saw is all I have.
My advice, buy lot's (like over 20). They are not expensive really. I will have to buy more as well as I am low. Just match them and store them so you know which pairs are matched and what the gains are.
We can talk about it when I see you next.
-Chris
I have a few, but not many. You probably were shown the 2SA970 and 2SC2240 trays. What you saw is all I have.
My advice, buy lot's (like over 20). They are not expensive really. I will have to buy more as well as I am low. Just match them and store them so you know which pairs are matched and what the gains are.
We can talk about it when I see you next.
-Chris
keypunch said:
Quasi, Ahmad, Shawn,
I am sorry, but I was not back home until 01:45 Tuesday morning from a activity I was running tad late for Monday morning. I started to create the PCBs that could be posted to this forum. Then while extracting the second image my system software went into a tailspin that it did not recover from. Happens at times generally for 40 minutes to couple hours odd time. This came to a terminal end (needed to power off/on my system) 18:40 Tuesday evening. Documenting and various special startup housekeeping I do on my system did not have my system back to post tailspin.
After I started creating the diyAudio "friendly" file size version of the PCBs I realized maybe it was a 2 pair PCB board version you wanted. I have one to 5 pair versions. I was going to post question to ask if the 4 output devices refered to 4 pairs or 4 total that equal 2 pairs. I saw Shawn's posting for 2 pair version. I always reference the designs based on number of pairs not number of output devices in total as most designs of this type only have pairs. This is in part why there was a further delay once I realize perhaps the total output device reference was being used. I had to go back and repeat the conversion process for the 2 pair version I already had as well. I have a number of changes for my own modifications to the board, but these modifications are still work in progress and very time consuming to keep all 1-5 pair versions in sync over and above the several hours to days of editing effort using a graphic editing program the modification have or will entail.
I then fine tuned the diyAudio images and seperated each to a seperate document. I keep the layout and track images in same file which is part of reason for file size exceed the diyAudio 100K limit. The files are vary in the 200K range depending on how many output devices the PCB image has. The PCB images I create will always be larger than those quasi creates. I do not have the software quasi uses so the PDF images I have created are not vector based data, but pixel based data. Pixel based data takes up far more space than a vector based image.
After a unexpect long call I received and a few technical refinements to the 2 pair PCB images to create in Acrobat PDF format the first image I will post is the tracks version to the currently latest version of the quasi PCB, the 20060903 version. The tracks and layout versions I am posting of the 2 pair PCB images will scale to actual size properly no matter what the printer DPI specification is as a result of these imahes being in PDF format. They also have the DC protection on each module board.
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 04:12
10 January 2007 04:32 Corrected file name. jlm
Re: Post #1305
Here is the layout for the 2 pair tracks PCB image I just posted re Post #1305.
My time will be much more limited over the next few weeks in case there are concerns about the 2 pair PCB images with the DC protection on the module baord. These are the "stock" quasi board whose only modifications are number of output devices, a bit of extra part number text and removal a a few "dead" end traces.
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 04:19
10 January 2007 04:34 Corrected file name. jlm
Here is the layout for the 2 pair tracks PCB image I just posted re Post #1305.
My time will be much more limited over the next few weeks in case there are concerns about the 2 pair PCB images with the DC protection on the module baord. These are the "stock" quasi board whose only modifications are number of output devices, a bit of extra part number text and removal a a few "dead" end traces.
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 04:19
10 January 2007 04:34 Corrected file name. jlm
anatech said:
Chris,
What version of the 2SC2240 do you have, BL or GR? Have you measured any of the 2SC2240's or 2SA970 Hfe? I would be interested in what the measured hFE of the ones you have and ther eis no hurry for the request. I am not implying measure the hFE for all the ones you have right now, just a couple from what you have of each of these two.
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 04:45
Chris,
Thanks so much. I know off hand the 2SC2240's I have are the BL's and the few I sampled before I bought them were in the 400 range. This increases my confidence the ones I have are likely OEM, not knock offs. I will need to check my 2SA9xx part. I think it was a 2SA992 as I seem to recall the store did not carry the 2SA970's, but I may be wrong. It appears the 2SA970 is an excellent device like he 2SC2240, though the 2SA992 is not too bad either,
Just out of curiosity what might be the general price you pay for your 2SA2240BL's and 2SA970's? I assume you purchase from a US supplier?
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 10:51
Thanks so much. I know off hand the 2SC2240's I have are the BL's and the few I sampled before I bought them were in the 400 range. This increases my confidence the ones I have are likely OEM, not knock offs. I will need to check my 2SA9xx part. I think it was a 2SA992 as I seem to recall the store did not carry the 2SA970's, but I may be wrong. It appears the 2SA970 is an excellent device like he 2SC2240, though the 2SA992 is not too bad either,
Just out of curiosity what might be the general price you pay for your 2SA2240BL's and 2SA970's? I assume you purchase from a US supplier?
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 10:51
To-220 Layout?
Quasi,
Your proposal of a new layout for to220-fets is very promising.
I always wanted to build your amp, but I never did because of your very good, but also very big PCB, a smaller version (for me without DC-Protection is perfectly ok, I have seperate Pcb for that pupose)
would be great.
The maximum size, I am able to etch is 100x160mm....I think many other diyers also have these limitations.
BTW wich version of the schematic (and layouts) is the latest one?
Thanks for info
Black
Quasi,
Your proposal of a new layout for to220-fets is very promising.
I always wanted to build your amp, but I never did because of your very good, but also very big PCB, a smaller version (for me without DC-Protection is perfectly ok, I have seperate Pcb for that pupose)
would be great.
The maximum size, I am able to etch is 100x160mm....I think many other diyers also have these limitations.
BTW wich version of the schematic (and layouts) is the latest one?
Thanks for info
Black
Latest Schematics and Layouts
Black,
Below I believe are the latest PCB and schematics for the MOSFET version of the quasi amp and related items. It is in your best interests to take the time to read the thread before asking any questions. Many of the questions have already been answered in the thread, and at times different times with some additional insights. I have taken the time to find and collect all of the most related links to your question as it is one of the most often asked questions. Please note I have chosen to link to the posting and not the attachments on purpose so you can find the associated thread discussion before and/or after the related posting:
Table can be used as a guide when trying to determine output configurations for the amp module based only on the IRFP450 (different devices have different power handing abilities and there are many points in the thread that discuss this and how one can calculate with the power handing ability for the device you may choose to use or others have chosen to use), Post #285:
http://www.diyaudio.com/forums/showthread.php?postid=794932#post794932
Latest Schematic, Post #1123:
http://www.diyaudio.com/forums/showthread.php?postid=1008216#post1008216
Latest PCB layout for 3 output pair devices, AKA NMOS350, Post #1034:
http://www.diyaudio.com/forums/showthread.php?postid=996722#post996722
Latest PCB tracks for 3 output pair devices, AKA NMOS350, Post #1035:
http://www.diyaudio.com/forums/showthread.php?postid=996723#post996723
Latest PCB layout for High Power 5 output pair devices, AKA NMOS500, Post #1036:
http://www.diyaudio.com/forums/showthread.php?postid=996725#post996725
Latest PCB tracks for High Power 5 output pair devices, AKA NMOS500, Post #1037:
http://www.diyaudio.com/forums/showthread.php?postid=996726#post996726
R9 to be 33r0 or 39r0 difference between latest schematic and latest PCB images, Post #1102:
http://www.diyaudio.com/forums/showthread.php?postid=999762#post999762
Current R6 values for different supply rail voltages, Post #1025:
http://www.diyaudio.com/forums/showthread.php?postid=996556#post996556
One part of background to R6 (known as R7 on much older schematic) item 2 reply in posting, Post #159:
http://www.diyaudio.com/forums/showthread.php?postid=600848#post600848
Bench Setup Guide for module once completed, Post #644:
http://www.diyaudio.com/forums/showthread.php?postid=945215#post945215
Schematic very close to current schematic above missing some a couple corrections to current schematic but this one has the currents shown on the schematic that are still valid and correct that may be useful, Post #325:
http://www.diyaudio.com/forums/showthread.php?postid=818662#post818662
Slow Turn On Schematic, Post #224:
http://www.diyaudio.com/forums/showthread.php?postid=784687#post784687
Slow Turn On PCB layout, Post #217:
http://www.diyaudio.com/forums/showthread.php?postid=783781#post783781
Slow Turn On PCB tracks, Post #218:
http://www.diyaudio.com/forums/showthread.php?postid=783783#post783783
The DC Detect schematic which is not in the amplifier schematic, but is part of the amplifier PCB modules for the amplifier (except for the first posting of the PCBs), Post #191:
http://www.diyaudio.com/forums/showthread.php?postid=776114#post776114
A standalone version of the DC Detect PCB (layout and tracks) used on the amp module board and has two DC Detect circuits on the one PCB, Post #853:
http://www.diyaudio.com/forums/showthread.php?postid=972400#post972400
As footnote one can make a standalone version of the DC Detect as a single board with a bit of effort using the base module PCB using a graphics editing program or (I have not tried) actually cutting it out from the printed paper images.
How to mount T8, the TO-92 (cbe) Vbe, to heatsink, Post #321:
http://www.diyaudio.com/forums/showthread.php?postid=800468#post800468
There is a BiPolar version of the amplifier as well known as the "Brother of Quasi".
http://www.diyaudio.com/forums/showthread.php?threadid=88258
Last posting of the BiPolar version schematic in the MOSFET thread, Post #1149:
http://www.diyaudio.com/forums/showthread.php?postid=1029087#post1029087
For the BiPolar version please refer to the dedicated thread for the "Brother of Quasi", but to save duplicate questions on things like PSU, slow start, DC Detect, Input stage and perhaps the predriver and related alternate part values you should consult this thread as much of the design and related questions could be duplicates of what has already been well covered on the base design.
I am not sure if the same alternate values for the R6 like resistor in the BiPolar design apply for different PSU rail voltages. You will need to ask quasi that question.
I trust this is not just helpful to Black, but to other current and future builders of the quasi MOSFET amplifier. After I post this I will double check I have all the links matched up with the link description and hope I can validate and do any required corrections before the post time limit for editing a post expires.
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 18:00 - 20:24
10 January 2007 20:33 Corrected link copy/paste for Post #224
10 January 2007 20:44 Typo correction and new point re R6 like resistor for BiPolar design.
10 January 2007 20:48 Minor spacing correction. Hopefully all links for post are correct now as I have checked all the links in the posting as best can without going crossed eyed.
10 January 2007 20:50 Opps, corrected typo error missed
BlacK_Chicken said:
Black,
Below I believe are the latest PCB and schematics for the MOSFET version of the quasi amp and related items. It is in your best interests to take the time to read the thread before asking any questions. Many of the questions have already been answered in the thread, and at times different times with some additional insights. I have taken the time to find and collect all of the most related links to your question as it is one of the most often asked questions. Please note I have chosen to link to the posting and not the attachments on purpose so you can find the associated thread discussion before and/or after the related posting:
Table can be used as a guide when trying to determine output configurations for the amp module based only on the IRFP450 (different devices have different power handing abilities and there are many points in the thread that discuss this and how one can calculate with the power handing ability for the device you may choose to use or others have chosen to use), Post #285:
http://www.diyaudio.com/forums/showthread.php?postid=794932#post794932
Latest Schematic, Post #1123:
http://www.diyaudio.com/forums/showthread.php?postid=1008216#post1008216
Latest PCB layout for 3 output pair devices, AKA NMOS350, Post #1034:
http://www.diyaudio.com/forums/showthread.php?postid=996722#post996722
Latest PCB tracks for 3 output pair devices, AKA NMOS350, Post #1035:
http://www.diyaudio.com/forums/showthread.php?postid=996723#post996723
Latest PCB layout for High Power 5 output pair devices, AKA NMOS500, Post #1036:
http://www.diyaudio.com/forums/showthread.php?postid=996725#post996725
Latest PCB tracks for High Power 5 output pair devices, AKA NMOS500, Post #1037:
http://www.diyaudio.com/forums/showthread.php?postid=996726#post996726
R9 to be 33r0 or 39r0 difference between latest schematic and latest PCB images, Post #1102:
http://www.diyaudio.com/forums/showthread.php?postid=999762#post999762
Current R6 values for different supply rail voltages, Post #1025:
http://www.diyaudio.com/forums/showthread.php?postid=996556#post996556
One part of background to R6 (known as R7 on much older schematic) item 2 reply in posting, Post #159:
http://www.diyaudio.com/forums/showthread.php?postid=600848#post600848
Bench Setup Guide for module once completed, Post #644:
http://www.diyaudio.com/forums/showthread.php?postid=945215#post945215
Schematic very close to current schematic above missing some a couple corrections to current schematic but this one has the currents shown on the schematic that are still valid and correct that may be useful, Post #325:
http://www.diyaudio.com/forums/showthread.php?postid=818662#post818662
Slow Turn On Schematic, Post #224:
http://www.diyaudio.com/forums/showthread.php?postid=784687#post784687
Slow Turn On PCB layout, Post #217:
http://www.diyaudio.com/forums/showthread.php?postid=783781#post783781
Slow Turn On PCB tracks, Post #218:
http://www.diyaudio.com/forums/showthread.php?postid=783783#post783783
The DC Detect schematic which is not in the amplifier schematic, but is part of the amplifier PCB modules for the amplifier (except for the first posting of the PCBs), Post #191:
http://www.diyaudio.com/forums/showthread.php?postid=776114#post776114
A standalone version of the DC Detect PCB (layout and tracks) used on the amp module board and has two DC Detect circuits on the one PCB, Post #853:
http://www.diyaudio.com/forums/showthread.php?postid=972400#post972400
As footnote one can make a standalone version of the DC Detect as a single board with a bit of effort using the base module PCB using a graphics editing program or (I have not tried) actually cutting it out from the printed paper images.
How to mount T8, the TO-92 (cbe) Vbe, to heatsink, Post #321:
http://www.diyaudio.com/forums/showthread.php?postid=800468#post800468
There is a BiPolar version of the amplifier as well known as the "Brother of Quasi".
http://www.diyaudio.com/forums/showthread.php?threadid=88258
Last posting of the BiPolar version schematic in the MOSFET thread, Post #1149:
http://www.diyaudio.com/forums/showthread.php?postid=1029087#post1029087
For the BiPolar version please refer to the dedicated thread for the "Brother of Quasi", but to save duplicate questions on things like PSU, slow start, DC Detect, Input stage and perhaps the predriver and related alternate part values you should consult this thread as much of the design and related questions could be duplicates of what has already been well covered on the base design.
I am not sure if the same alternate values for the R6 like resistor in the BiPolar design apply for different PSU rail voltages. You will need to ask quasi that question.
I trust this is not just helpful to Black, but to other current and future builders of the quasi MOSFET amplifier. After I post this I will double check I have all the links matched up with the link description and hope I can validate and do any required corrections before the post time limit for editing a post expires.
Regards,
John L. Males
Willowdale, Ontario
Canada
10 January 2007 18:00 - 20:24
10 January 2007 20:33 Corrected link copy/paste for Post #224
10 January 2007 20:44 Typo correction and new point re R6 like resistor for BiPolar design.
10 January 2007 20:48 Minor spacing correction. Hopefully all links for post are correct now as I have checked all the links in the posting as best can without going crossed eyed.
10 January 2007 20:50 Opps, corrected typo error missed
Mini - Quasi
Here's the mini board. Could be used for multi-channel amplifiers, but also compact stereo units. Has been designed for rails up to +/- 55v (FET dependant).
Not built or tested so please check layout against schematic if you decide to use it before I build one.
As promised PCB is 75mm x 90mm (not including heatsink bracket). Have fun....
Cheers
Q
Here's the mini board. Could be used for multi-channel amplifiers, but also compact stereo units. Has been designed for rails up to +/- 55v (FET dependant).
Not built or tested so please check layout against schematic if you decide to use it before I build one.
As promised PCB is 75mm x 90mm (not including heatsink bracket). Have fun....
Cheers
Q
