electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Articles  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links  |  Store
Forum with support of Syndicator RSS
 FAQFAQ   CalendarCalendar   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   LinksLinks
 RegisterRegister   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in  Chat RoomChat Room 
Live streaming at radio.electro-music.com

  host / artist show at your time
  Various Artists ~ 2014 Autumnal Equinox ~ live streaming radio ~
Please visit the chat
 Forum index » DIY Hardware and Software » Lunettas - circuits inspired by Stanley Lunetta
LED rate blinking confusion
Post new topic   Reply to topic Moderators: mosc
Page 1 of 1 [7 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
animalman



Joined: Jan 21, 2013
Posts: 9
Location: out past midnight

PostPosted: Wed Nov 20, 2013 4:12 pm    Post subject: LED rate blinking confusion Reply with quote  Mark this post and the followings unread

Hey all, been lurking for quite a while after building some MFOS stuff.
First, big thanks for the deep well of information and charing inspiring work.

What has confused me a bit, is having a LED on the output of LFO/Osc.
You get a LED flash when the square is HIGH but never on the LOWs right? But I hear a tick (slow LFO) on both states of the cycle (high and low) but only LED indication on the high state of the cycle. So what I hear and what I see don't match up. Flashing at half the rate of the ticking SOUND.
Is this me doing something wrong. Or should I get me ears checked? Wink

Thanks in advance
-animalman
Back to top
View user's profile Send private message
Blue Hell
Site Admin


Joined: Apr 03, 2004
Posts: 20568
Location: The Netherlands, Enschede
Audio files: 147
G2 patch files: 318

PostPosted: Wed Nov 20, 2013 4:33 pm    Post subject: Reply with quote  Mark this post and the followings unread

What you actually hear are the state changes ... low->high and high->low ... the LED makes those same changes on->off and off->on. Maybe looking at it this way will solve the confusion?
_________________
Jan
Back to top
View user's profile Send private message Visit poster's website
analog_backlash



Joined: Sep 04, 2012
Posts: 391
Location: Aldershot, UK
Audio files: 21

PostPosted: Wed Nov 20, 2013 4:58 pm    Post subject: Reply with quote  Mark this post and the followings unread

You beat me to it Jan!

I'd add a welcome to animalman and say that being a square wave, the cone of your speaker moves in suddenly on the low-high transition and out suddenly on the high-low transition, producing two clicks. The LED only comes on during the high phase.

Hope that helps,

Gary
Back to top
View user's profile Send private message
Blue Hell
Site Admin


Joined: Apr 03, 2004
Posts: 20568
Location: The Netherlands, Enschede
Audio files: 147
G2 patch files: 318

PostPosted: Wed Nov 20, 2013 5:33 pm    Post subject: Reply with quote  Mark this post and the followings unread

Hah, and you beat me to that Gary Laughing

welcome animalman

_________________
Jan
Back to top
View user's profile Send private message Visit poster's website
animalman



Joined: Jan 21, 2013
Posts: 9
Location: out past midnight

PostPosted: Thu Nov 21, 2013 10:42 am    Post subject: Reply with quote  Mark this post and the followings unread

thanks for the warm welcome! Very Happy

Wow you guys are quick to answer. And both of your replies really makes
perfect sense.
Back to top
View user's profile Send private message
JingleJoe



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Thu Dec 05, 2013 5:07 am    Post subject: Reply with quote  Mark this post and the followings unread

I also feel the desire to add that when the LFO is in the high or low state, there is nothing to hear because it's essentially DC (if we're talking about a square wave here). You hear the transitions because they have more high frequency harmonics than something which is, for all intents and purposes 0Hz.
_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
analog_backlash



Joined: Sep 04, 2012
Posts: 391
Location: Aldershot, UK
Audio files: 21

PostPosted: Thu Dec 05, 2013 8:08 am    Post subject: Reply with quote  Mark this post and the followings unread

Hi

JingleJoe wrote:
I also feel the desire to add that when the LFO is in the high or low state, there is nothing to hear because it's essentially DC (if we're talking about a square wave here). You hear the transitions because they have more high frequency harmonics than something which is, for all intents and purposes 0Hz.

That's perfectly true JingleJoe. In theory, it should be all of the odd harmonics. It reminds me of a (slightly sad) Fourier series program I did in QBASIC many, many years ago. If you add sine waves of frequency f, 3f, 5f etc together, you get a square(ish) result (see screen dump).

Gary


20 odd sines.gif
 Description:
 Filesize:  13.2 KB
 Viewed:  37 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

20 odd sines.gif


Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: mosc
Page 1 of 1 [7 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
 Forum index » DIY Hardware and Software » Lunettas - circuits inspired by Stanley Lunetta
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
e-m mkii

Please support our site. If you click through and buy from
our affiliate partners, we earn a small commission.


Forum with support of Syndicator RSS
Powered by phpBB © 2001, 2005 phpBB Group
Copyright © 2003 through 2009 by electro-music.com - Conditions Of Use