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
  EdisonRex Edison's Electronic Review
Please visit the chat
 Forum index » DIY Hardware and Software » Ken Stone designs - CGS
Bi N Tic filter section acting strange
Post new topic   Reply to topic Moderators: Scott Stites
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
6079smith



Joined: Jan 18, 2007
Posts: 95
Location: Mark of the Dane
Audio files: 4

PostPosted: Wed Mar 14, 2012 2:47 am    Post subject: Bi N Tic filter section acting strange
Subject description: ...when it decides to do anything at all
Reply with quote  Mark this post and the followings unread

I'm stumped with this... I have a bintic that seems to be doing fine, up to a point. The oscillator is working well enough (healthy signals from the saw and square outputs *bridechamber PCB* and from the transistor input to the 4024) but the output after the filter is so low it can barely be heard, or else it sounds like a geiger counter when the tune pots are at very specific points. I can put a signal through the filter and again, it sounds like it's almost working. Damping (resonance) and Bandwith pots do very little, and need to be at their extremes for any audio to pass. I've tried swapping the CMOS chips, same results. The four opamps in the filter section seem okay as well. The only odd thing about the PCB is that the connections between the 4024 and the 4051s are backwards (pins 9, 11 and 12 on the 4024 go to pins 11, 10 and 9 respectivley, backwards w/r/t the schematic). Noticable problem: signal comes in bursts while twisting the tune pot, then fades after 1-2 seconds.
What am I missing? Bad capacitors?
Back to top
View user's profile Send private message
Sebo



Joined: Apr 27, 2007
Posts: 534
Location: Argentina

PostPosted: Wed Mar 14, 2012 8:20 am    Post subject: Reply with quote  Mark this post and the followings unread

I think that's how should work.
In mine with bandwidth at 0, no audio will pass. Also with resonance at 0, I have to turn bandwidth really high to hear something.
Normally I start with bandwidth at max an resonance to zero and start tweaking from that.
With both reso an bandwidth to max the output should be really high, but it depends a lot of the frequency and the signal input.
Have in mind that is a comb filter.

_________________
Sebo
---------------------------------------
My Music:
www.cosaquitosenglobo.com.ar
www.myspace.com/cosaquitosenglobo
Back to top
View user's profile Send private message
6079smith



Joined: Jan 18, 2007
Posts: 95
Location: Mark of the Dane
Audio files: 4

PostPosted: Wed Mar 14, 2012 10:27 am    Post subject: Reply with quote  Mark this post and the followings unread

Okay, interesting. I just figured it would give an output as a regular VCO. I've only done rudimentary experiments with an actual audio input (basically just to test it worked), looks like I'll have to delve a bit deeper.
Thanks for the help.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: Scott Stites
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 » Ken Stone designs - CGS
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