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

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, etc.

Simplistic NJFET RIAA
Simplistic NJFET RIAA
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 9th August 2014, 07:40 PM   #13151
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Simplistic NJFET RIAA
Quote:
Originally Posted by stajo View Post

I also think this is how I will arrange R1+ Rx1-4

47 47 18 18 6,8

This gives me those combinations:

47//47 = 23,5
47//18 = 13,5
47//47//18 = 10,2
47//18//18 = 7,55
47//6,8 = 5,94
47//47//18//6,8 = 4,08
47//18//18//6,8 = 3,58
47//47//18//18//6,8 = 3,33

And 47 alone ofc. Thoughts about that?
That's a very nice load range to listen to the Dyna 10X5.
  Reply With Quote
Old 9th August 2014, 07:45 PM   #13152
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Simplistic NJFET RIAA
Quote:
Originally Posted by stajo View Post
Polaris Electronics.

Ok, I'll arrange it like this:
Ch1 Q4 8,44 Q5 7,14, Q6 8,27
Ch2 Q4 8,56 Q5 7,71, Q6 8,72

tomorrow
I would swap the Ch2 Q5, Q6 to Ch1. Since Ch2 Q4 will drop a bit more than Ch1 Q4 from B+ not to continue the trend.
  Reply With Quote
Old 9th August 2014, 07:49 PM   #13153
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Simplistic NJFET RIAA
Quote:
Originally Posted by Salas View Post
I would swap the Ch2 Q5, Q6 to Ch1. Since Ch2 Q4 will drop a bit more than Ch1 Q4 from B+ not to continue the trend.
Right, thanks. Q5-6 is a follower just adding current, not gain right?
  Reply With Quote
Old 9th August 2014, 08:06 PM   #13154
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Simplistic NJFET RIAA
Right. So it will drop some voltage across R11 analogous to Q5 IDSS.
  Reply With Quote
Old 10th August 2014, 07:47 AM   #13155
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Simplistic NJFET RIAA
Just found out that I had ordered some extra K170 from Mike. Those had better coherence to my measuring method. Unfortunately none in the Q4 region.

So if I arrange it:
Ch1 Q4 8,44 Q5 7,71, Q6 8,72
Ch2 Q4 8,56 Q5 7,14, Q6 8,27

Is there any reason for me to change for example Ch 1 Q4 from 7,71 to a 7,14?

The 9ers is ordered as a quad. I dont remember what project I had in mind but maybe I should keep that as a quad and not use it as Q6es.
Attached Images
File Type: jpg FSP 001 (2000x3000).jpg (287.4 KB, 223 views)
  Reply With Quote
Old 10th August 2014, 01:04 PM   #13156
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Simplistic NJFET RIAA
Soldered up and tested the PSU meanwhile. 41,5 AC sec unloaded, about 49,5 VDC@127 mA (390R dummy) and 48,5@145mA (335R). Might eventually sneak up to the 50 depending on the final setting. Am I clear with that or do I need to us the RD/Link?
Attached Images
File Type: jpg FSP 002 (3000x2000).jpg (652.8 KB, 217 views)
File Type: jpg FSP 003 (3000x2000).jpg (774.8 KB, 201 views)
File Type: jpg FSP 004 (3000x2000).jpg (651.2 KB, 196 views)
File Type: jpg FSP 005 (3000x2000).jpg (448.9 KB, 191 views)
File Type: jpg FSP 006 (3000x2000).jpg (470.0 KB, 119 views)
  Reply With Quote
Old 10th August 2014, 01:08 PM   #13157
AndrewT is offline AndrewT  Scotland
R.I.P.
 
Join Date: Jul 2004
Location: Scottish Borders
What output voltage do you get at maximum supply voltage as the input?
__________________
regards Andrew T.
  Reply With Quote
Old 10th August 2014, 01:18 PM   #13158
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Simplistic NJFET RIAA
Quote:
Originally Posted by AndrewT View Post
What output voltage do you get at maximum supply voltage as the input?
Do you meen unloaded, with just the C and the bleeders?
  Reply With Quote
Old 10th August 2014, 02:41 PM   #13159
AndrewT is offline AndrewT  Scotland
R.I.P.
 
Join Date: Jul 2004
Location: Scottish Borders
yes, if the supply rail fuses blow, or you turn the quiescent current right down, or you disconnect one amplifier and test the other one.
__________________
regards Andrew T.
  Reply With Quote
Old 10th August 2014, 02:51 PM   #13160
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Simplistic NJFET RIAA
Aha. I dont have the boards all populated yet. Still figuring a few LCD and FET measures out before soldering. Later
  Reply With Quote

Reply


Simplistic NJFET RIAAHide 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


New To Site? Need Help?

All times are GMT. The time now is 04:12 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki