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
Please visit the chat
 Forum index » DIY Hardware and Software » Thomas Henry designs
VCO 4046 triangle trim problem
Post new topic   Reply to topic Moderators: Scott Stites
Page 1 of 1 [1 Post]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
lorencz



Joined: Oct 04, 2015
Posts: 16
Location: Detroit
Audio files: 2

PostPosted: Sun May 08, 2016 8:57 am    Post subject: VCO 4046 triangle trim problem Reply with quote  Mark this post and the followings unread

I built the 4046 vco, and it's pretty cool. The saw wave is great! But I'm having trouble setting up the triangle. I get the falling side of the triangle, but the rising side seems to be missing, or rather, not inverted. The first thing I did was switch out the TL074 thinking the op amp doing the summing and inverting of the two ramps might be bad, but it didn't help. The first scope picture is the closest I can get to a triangle. The second and third shots are the voltages on pins 9 and 10 of IC3c.

The other relevant bit: the voltages from pin 6 and 7 of the 4046 are both falling ramps. Should one of them be rising?

Lastly, as expected, the voltage on pin 4 of the 4046 is a pulse wave.


P_20160508_113654.jpg
 Description:
 Filesize:  1.44 MB
 Viewed:  170 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

P_20160508_113654.jpg



P_20160508_114112.jpg
 Description:
 Filesize:  1.55 MB
 Viewed:  169 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

P_20160508_114112.jpg



P_20160508_114228.jpg
 Description:
 Filesize:  1.59 MB
 Viewed:  134 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

P_20160508_114228.jpg


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: Scott Stites
Page 1 of 1 [1 Post]
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 » Thomas Henry designs
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