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
  Faux Pas Quartet and friends Music From Last Thursday
Please visit the chat
 Forum index » DIY Hardware and Software
Should I use 1 transistor array for 2 exponential converters
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [3 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
okelk



Joined: May 08, 2014
Posts: 29
Location: Vienna

PostPosted: Sun Aug 31, 2014 7:02 am    Post subject:  Should I use 1 transistor array for 2 exponential converters
Subject description: I'm building a Rene Schmitz 4069 vco!
Reply with quote  Mark this post and the followings unread

Hi!

I want to build a dual 4069 vco (by Rene Schmitz http://www.schmitzbits.de/vco4069.html ) on one little pcb.
I replaced the pwm with a opamp version so I only need 1 cd4049 plus 1 tl074 for 2 VCOs...also the edges of the pulse wave are a bit 'sharper'.
It's working quite well on a breadboard so far...

I thought that it would be convinient to use a ca3096 (3 NPN + 2 PNP) for the two exponential converters.
My question is:
Is it ok two have two exponential converters i one packadge??
And if so, if I want to use a tempco , do I just stick both of them on op of the ca3096?

And also, would it be ok to use the 'leftover' NPN in the ca3096 for something else, or could it disturb the tempco somehow?
Back to top
View user's profile Send private message
JovianPyx



Joined: Nov 20, 2007
Posts: 1249
Location: West Red Spot, Jupiter
Audio files: 161

PostPosted: Sun Aug 31, 2014 3:32 pm    Post subject: Reply with quote  Mark this post and the followings unread

I can't help with the array, but I noticed that you cited a part CD4049. I assume that you meant 4069. The circuit was designed for a 4069 and may not work correctly with 4049.

Also, it may not be advisable to put 2 VCOs on one 4069. I realize that there are enough gates, but the close internal power coupling of the two circuits on the same IC may have a problem with soft synch. There can also be a sensitivity to the exact gates that are use for schmitt trigger and integrator.

Hopefully Rene will see this.

_________________
FPGA, dsPIC and Fatman Synth Stuff

Time flies like a banana.
Fruit flies when you're having fun.
BTW, Do these genes make my ass look fat?
corruptio optimi pessima
Back to top
View user's profile Send private message Visit poster's website
okelk



Joined: May 08, 2014
Posts: 29
Location: Vienna

PostPosted: Sun Aug 31, 2014 4:40 pm    Post subject: Reply with quote  Mark this post and the followings unread

JovianPyx wrote:
I can't help with the array, but I noticed that you cited a part CD4049. I assume that you meant 4069. The circuit was designed for a 4069 and may not work correctly with 4049.

Oh...Yes,of course....I did mean the 4069...

JovianPyx wrote:

Also, it may not be advisable to put 2 VCOs on one 4069. I realize that there are enough gates, but the close internal power coupling of the two circuits on the same IC may have a problem with soft synch. There can also be a sensitivity to the exact gates that are use for schmitt trigger and integrator.

Hopefully Rene will see this.


I haven't thought of this, I only tried halve of what I want to build on a breadboard using the same pin configuration as in renes schematic...
I do remember reading in some other thread that somebody build a 4069 vco and a different pin configuration didn't work.
I guess the only way to find out is to try it.

EDIT: Oh...I just found that thread again ( http://electro-music.com/forum/topic-60189.html&postorder=asc ). You were the one where the different pin configuration didn't work!
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [3 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
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