Debugging my Aikido - Page 3 - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 5th July 2005, 09:40 PM   #21
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
Quote:
moamps may be right on the mark about your transformers- saturating trannies throw out an amazing amount of field.
In that case I would expect the other channel to have the same amout of hum.

Quote:
I suppose you've tried swapping valves between channels just in case its heater/cathode leakage
Yes..
  Reply With Quote
Old 5th July 2005, 09:41 PM   #22
moamps is offline moamps  Croatia
diyAudio Member
 
Join Date: Oct 2002
Location: Croatia
Quote:
Originally posted by Bas Horneman
1/100 would be .1 sec/div right?
It's .01sec/div.

Quote:
It only has one channel..that is Y right?
Yes.

Quote:
or should it go on X..x says trigger..
The trigger should be set to internal, or to X input if the external trigger signal is used.

Regards,
Milan
  Reply With Quote
Old 5th July 2005, 09:46 PM   #23
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
Quote:
It's .01sec/div.
So with my scope I would have to set it to 10m and then X10 ?

If I do that I get roughly one wave on my display!

The scope is a Tektronix T921
Quote:
The trigger should be set to internal, or to X input if the external trigger signal is used.
Ok..I had it on there but now I understand why it is there!

Thanx Milan..
  Reply With Quote
Old 5th July 2005, 09:58 PM   #24
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
I am using the 12Volt part of the ECC99 i.e. 12 volt to pin 4 and 0 to pin5....but I have left pin 9 disconnected...should I have earthed it?

[edit] earthed it ...does not make one iota difference.....funny would at least expect to see something...
  Reply With Quote
Old 5th July 2005, 10:06 PM   #25
EC8010 is offline EC8010  United Kingdom
diyAudio Moderator Emeritus
 
EC8010's Avatar
 
Join Date: Jan 2003
Location: Near London. UK
If you listen and switch (only) the pre-amplifier off, does the hum go away immediately?
__________________
The loudspeaker: The only commercial Hi-Fi item where a disproportionate part of the budget isn't spent on the box. And the one where it would make a difference...
  Reply With Quote
Old 5th July 2005, 10:13 PM   #26
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
Quote:
If you listen and switch (only) the pre-amplifier off, does the hum go away immediately?
yes
  Reply With Quote
Old 5th July 2005, 10:37 PM   #27
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
I don't know why..maybe because I've set the scope according to moamps...but now at least a part of the puzzle is falling into place.

If I measure now before the cap the sine wave is exactly the same as after the cap....!!!!

I've compared both channels with each other...I now seem to be able to test ripple on the b+ ...which I could not do before on the milliamp level....

all measurements are exactly the same except on pin 6 where the one channel is quiet and the other has one has hum..

b+ of 10mV peak to peak is not too bad is it? The ripple on the output looks to be around 1/2 that of the b+ ripple.
  Reply With Quote
Old 5th July 2005, 10:52 PM   #28
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
OK, that's more sensible. Now you can chase more logical sources of ground loops and induction.
__________________
The more you pay for it, the less inclined you are to doubt it.- George Smiley
  Reply With Quote
Old 5th July 2005, 11:07 PM   #29
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
B I N G O !!!!!

Don't know why I did not spot it before...it took a resistor from pin7 to loosen............ to spot that the other 100k resistor was connected to pin 6 instead of 7. (In other words the bottom 100k resistor was connected to pin 6 instead of 7..duh)
  Reply With Quote
Old 5th July 2005, 11:08 PM   #30
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
Thanks ALL for helping me!

Now for the listening test
  Reply With Quote

Reply


Hide 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Debugging hiss in old receiver mashaffer Solid State 39 13th February 2012 03:34 PM
Debugging a Sony TA-1055 oddbjorn Solid State 19 24th October 2010 11:24 AM
Debugging a PIMETA headphone amp Atilla Headphone Systems 3 23rd April 2009 05:12 PM
Debugging TDA1541a DAC PSU FibCouple Digital Source 13 19th November 2008 01:59 AM
Debugging Quasi amp cm961 Solid State 7 3rd February 2004 11:54 PM


New To Site? Need Help?

All times are GMT. The time now is 05:23 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2