electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links
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 
 Forum index » DIY Hardware and Software
Super Simple Quad Saw/Pulse VCO out of one 40106
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [6 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
synthmonger



Joined: Nov 16, 2006
Posts: 578
Location: flada
Audio files: 3

PostPosted: Wed Jun 10, 2009 11:13 am    Post subject: Super Simple Quad Saw/Pulse VCO out of one 40106 Reply with quote  Mark this post and the followings unread

I haven't tested more than three VCO's running at a time from a single 40106 but it works pretty darn well! There is some very minimal bleed-thru but only really noticeable if you're trying to hear it. Tracking can be a bit iffy!

I haven't tested the sync with oscillators other than 40106 VCOs but it seems to work pretty well. I may come up with a slightly more sophisticated sync method using Fet switching or something. If anyone encounters problems please let me know!


You can leave off the Pulse width op-amps if you want just a Saw VCO. You can also use a quad op-amp instead of duals. They must be TL072 or equivalents. LM358 and the like aren't suitable replacements.

I did plan on making it 3 VCO's using two hex inverters. One for the saw core the other for the pulsewidth modulation but I could only get 1-50% duty cycle or 50-90% not 1-100%.


SS_40106VCO.jpg
 Description:
 Filesize:  94.47 KB
 Viewed:  1600 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

SS_40106VCO.jpg



_________________
Youtube!
modular demos!
Whacky tunes!

Last edited by synthmonger on Sat Jun 20, 2009 2:48 pm; edited 2 times in total
Back to top
View user's profile Send private message Visit poster's website
widdly



Joined: Jun 25, 2007
Posts: 268
Location: singapore
G2 patch files: 2

PostPosted: Wed Jun 10, 2009 7:52 pm    Post subject: Reply with quote  Mark this post and the followings unread

Thanks for posting.

I built one of your earlier 40106 designs and I had a problem with it. It stopped oscillating at the top end of the CV scale, but before it went out of my hearing range. Have you noticed this? I was looking to use one for a simple VC clock.

Last edited by widdly on Thu Aug 05, 2010 10:01 pm; edited 1 time in total
Back to top
View user's profile Send private message
synthmonger



Joined: Nov 16, 2006
Posts: 578
Location: flada
Audio files: 3

PostPosted: Thu Jun 11, 2009 3:29 pm    Post subject: Reply with quote  Mark this post and the followings unread

Yeah it happened to me because of bad a transistor and I think it also happened because one was reversed.
_________________
Youtube!
modular demos!
Whacky tunes!
Back to top
View user's profile Send private message Visit poster's website
synthmonger



Joined: Nov 16, 2006
Posts: 578
Location: flada
Audio files: 3

PostPosted: Sat Jun 20, 2009 2:52 pm    Post subject: Reply with quote  Mark this post and the followings unread

I did some more tests with this module and found that a max of 4 stableish vcos are obtainable. Any time you're using the inverters next to each other will cause some annoying bleedthru and unnecessary cross modulation.

Anywhos if you the following pins you will be set.
1-2
5-6
13-12
9-8

Ground pins 3 and 11

_________________
Youtube!
modular demos!
Whacky tunes!

Last edited by synthmonger on Sat Jun 20, 2009 6:34 pm; edited 1 time in total
Back to top
View user's profile Send private message Visit poster's website
richardc64



Joined: Jun 01, 2006
Posts: 679
Location: NYC
Audio files: 26

PostPosted: Sat Jun 20, 2009 6:14 pm    Post subject: Reply with quote  Mark this post and the followings unread

Since you say to ground pin 3, I believe you meant to say use pins 5-6, not 4-6. No?
_________________
Revenge is a dish best served with a fork... to the eye
Back to top
View user's profile Send private message Visit poster's website
synthmonger



Joined: Nov 16, 2006
Posts: 578
Location: flada
Audio files: 3

PostPosted: Sat Jun 20, 2009 6:34 pm    Post subject: Reply with quote  Mark this post and the followings unread

Yes my mistake. I edited the post to reflect the correct pins.
_________________
Youtube!
modular demos!
Whacky tunes!
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [6 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
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


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