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.

Valve Itch phono
Valve Itch phono
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 13th August 2013, 05:13 PM   #1221
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Valve Itch phono
By setting delay and measuring time you can "zoom" into the startup phase to look for if the caps are sucking energy from the transformer that starts ringings.

I dont see any such tendencies here. Of course this has to do with many factors like the speed and size of caps etc. Inductors in the filter chain can also start interfere with caps and trannys in a bad way to show this edgy behaviour under startup.

Snubbers can be good but its very hard to test them out. There is no "one size fits all" value there. So if you cant test them out leave them out. They can certainly cause more harm then good.
Attached Images
File Type: png psudVIPh3.png (75.7 KB, 140 views)
  Reply With Quote
Old 13th August 2013, 05:21 PM   #1222
merlin el mago is offline merlin el mago
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
I ont' understand why the voltage at the load varies depending the ms and the delay?
  Reply With Quote
Old 13th August 2013, 05:30 PM   #1223
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Valve Itch phono
Quote:
Originally Posted by merlin el mago View Post
I ont' understand why the voltage at the load varies depending the ms and the delay?
I presume that you by "voltage at the load" meen V(I1) in this case. It shows minimum value and maximum value over the voltage over load (I1). Third column "Diff" is "Max minus Min voltage over load".

If you set the measurment with a delay long enough so caps has charged and startup phase is over then "Diff" is "ripple under run".

If you set it with no delay "Diff" is "Zero to Max voltage" which is not very interesting if youre looking for ripple.

Does that make sense?
  Reply With Quote
Old 13th August 2013, 05:39 PM   #1224
merlin el mago is offline merlin el mago
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
Yes I wanna say V(l1) as voltage at the load.

Diff is only ripple at the start up or is continous ripple when run?
  Reply With Quote
Old 13th August 2013, 06:07 PM   #1225
stajo is offline stajo  Sweden
diyAudio Member
 
Join Date: Jun 2011
Location: Stockholm
Valve Itch phono
I made some pix for you. Maybe those say more then words. Look at measured time and delay at every picture and how the curves and measures change.

Its all the same circuit, just different measuring time and delay.
Attached Images
File Type: png psudVIPh4.png (113.2 KB, 140 views)
File Type: png psudVIPh5.png (90.4 KB, 131 views)
File Type: png psudVIPh6.png (98.7 KB, 127 views)
File Type: png psudVIPh7.png (111.7 KB, 123 views)
File Type: png psudVIPh8.png (114.8 KB, 50 views)
File Type: png psudVIPh9.png (109.4 KB, 52 views)
  Reply With Quote
Old 13th August 2013, 06:21 PM   #1226
merlin el mago is offline merlin el mago
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
Thanks for your work
  Reply With Quote
Old 13th August 2013, 06:46 PM   #1227
RCruz is offline RCruz  Switzerland
nhinstruments
diyAudio Member
 
RCruz's Avatar
 
Join Date: Sep 2006
Location: Wallis
Valve Itch phono
Hi Merlin

I remember you placed some small caps in the inputs of your itch... why ?
__________________
RC
  Reply With Quote
Old 13th August 2013, 06:47 PM   #1228
merlin el mago is offline merlin el mago
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
10nF between signal an ground to avoid antenna efect caused by the cables.
  Reply With Quote
Old 13th August 2013, 06:50 PM   #1229
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Valve Itch phono
Maybe between RCA ring and chassis?
  Reply With Quote
Old 13th August 2013, 06:59 PM   #1230
merlin el mago is offline merlin el mago
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
Actually I don't have any cap connected because the Itch runs dead like a tomb
  Reply With Quote

Reply


Valve Itch phonoHide 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
Got the build itch again. 80w kt88 itsmejto Tubes / Valves 44 26th September 2008 11:49 PM
valve phono stage wanted for mc brobarrie Swap Meet 1 13th August 2007 08:17 PM
Basic DIY Valve Phono Stage matthew2456 Tubes / Valves 5 29th March 2007 04:11 AM
Phono pre, valve or jfet lndm Analogue Source 7 4th April 2006 02:11 PM
phono preamp design for c3m postie valve fergs1 Tubes / Valves 1 29th May 2005 02:12 PM


New To Site? Need Help?

All times are GMT. The time now is 05:05 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki