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

Equipment & Tools From test equipment to hand tools

High pitched noise that isnt being picked up on scope?
High pitched noise that isnt being picked up on scope?
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 20th June 2020, 01:19 AM   #21
PRR is offline PRR  United States
diyAudio Member
 
PRR's Avatar
 
Join Date: Jun 2003
Location: Maine USA
High pitched noise that isnt being picked up on scope?
Quote:
Originally Posted by MarcelvdG View Post
Not being able to change the triggering sounds very 1950's.
"the scope is DSO188."

DSO188, mostly $35-$47.

It may just be too small to set trigger mode, with human fingers....

Trigger mode: Auto
Size: 57 x 34 x 11 mm
Weight: 40 grams
Attached Images
File Type: gif DSO188.gif (24.1 KB, 70 views)
  Reply With Quote
Old 20th June 2020, 08:08 AM   #22
MarcelvdG is offline MarcelvdG  Netherlands
diyAudio Member
 
Join Date: Mar 2003
Location: Haarlem, the Netherlands
Apparently it has a suspend button: "At any time, the waveform display (pause function) is frozen". If it then only displays the last trace it has captured, you may be able to see something that's too small to trigger on.
  Reply With Quote
Old 20th June 2020, 09:17 AM   #23
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
High pitched noise that isnt being picked up on scope?
I don't think you stand much chance of seeing this on the scope you mention, but if it is audible then it should be pretty easy on a conventional scope of decent bandwidth if you handle the controls correctly.
  Reply With Quote
Old 20th June 2020, 10:14 AM   #24
phofman is offline phofman  Czech Republic
diyAudio Member
 
Join Date: Apr 2005
Location: Pilsen
I do not know in this case, but often faint signals are audible because ear is averaging the noise. There are tests with audible signals encoded in dither. I do not think such signal would be discernable on single scope trace. But any soundcard with Arta/REW/even spectrogram in audacity will identify the peak easily.
  Reply With Quote
Old 20th June 2020, 11:35 AM   #25
Mark Tillotson is offline Mark Tillotson
diyAudio Member
 
Join Date: May 2018
Location: Cambridge UK
Have you compared it with a 15kHz test tone of the same perceived volume?

Is the scope in full bandwidth mode with probe set to 10x mode?

Could this be an intermodulation product from some higher frequencies beating?
  Reply With Quote
Old 20th June 2020, 03:20 PM   #26
MarcelvdG is offline MarcelvdG  Netherlands
diyAudio Member
 
Join Date: Mar 2003
Location: Haarlem, the Netherlands
Quote:
Originally Posted by phofman View Post
I do not know in this case, but often faint signals are audible because ear is averaging the noise. There are tests with audible signals encoded in dither. I do not think such signal would be discernable on single scope trace. But any soundcard with Arta/REW/even spectrogram in audacity will identify the peak easily.
You can definitely look deeper with a narrower noise bandwidth, so just about any kind of spectrum analyser (hardware, software or biological) will beat a scope when it comes to detecting faint tones in noise. Still, you usually need more SNR to properly trigger a scope than to see something on a single-shot trace.
  Reply With Quote
Old 22nd June 2020, 02:27 AM   #27
givemeyoursoul is offline givemeyoursoul
diyAudio Member
 
Join Date: Mar 2020
Quote:
Originally Posted by laserscrape View Post
There is a high pitched ringing (~15khz) coming from my system which seems to fluctuate in volume slightly, almost like tinnitus , which I assumed it was after checking on scope and seeing absolutely nothing.

But after checking more thoroughly it is definitely the system, test tones of any frequency show up clear as day, rapidly changing waveforms like music or noise still show up clearly even if the scope cant track them.
How could it be that this noise is not being picked up at all on the scope?

Also I could still hear the noise through the headphones as the scope was attached.
"The capacitors in the 35th precinct are screaming..."
  Reply to this post

Reply


High pitched noise that isnt being picked up on scope?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
high-pitched noise from vox amp theinkysquids Instruments and Amps 2 12th January 2020 02:11 AM
Xonar DX high pitched noise snow43 PC Based 6 19th June 2016 11:29 PM
High pitched noise heard in my Hyundai loninappleton Car Audio 0 16th December 2010 07:04 PM
Marantz 2235B with high pitched noise ... tchiwam Solid State 2 31st October 2010 03:43 PM
high pitched noise candyman122 Car Audio 7 7th January 2010 02:13 AM


New To Site? Need Help?

All times are GMT. The time now is 03:11 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki