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 
 Forum index » DIY Hardware and Software » Ken Stone designs - CGS
CGS35 Steiner Filter not self oscillating
Post new topic   Reply to topic Moderators: Scott Stites
Page 1 of 1 [2 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
bubzy



Joined: Oct 27, 2010
Posts: 552
Location: United Kingdom
Audio files: 61

PostPosted: Wed Apr 18, 2012 3:40 am    Post subject: CGS35 Steiner Filter not self oscillating Reply with quote  Mark this post and the followings unread

Hi,
I have bought a few of the cgs35 and find it to be an awesome filter, however i have built one in the past that self oscillated (i cannot remember the link but it was a pcb designed by a japanese guy).
is there anyway to modify the cgs35 to self oscillate? its kinda useful as an fm source.

_________________
_Richard_ Smile
Back to top
View user's profile Send private message
jumunius



Joined: Apr 19, 2010
Posts: 346
Location: San Francisco, CA
Audio files: 13

PostPosted: Wed Apr 18, 2012 3:01 pm    Post subject: Reply with quote  Mark this post and the followings unread

From Ken's site:

"When using 2N3904 and 2N3906 I had to tweak the 2k2 in the resonance part of the circuit (connected to the emitter of the NPN in the amplifier) to compensate for transistor gain. A 15k across it brought it to the point where with the resonance full up, it was slightly ringing. A signal on the HP or LP inputs would then send it onto full oscillation, requiring the resonance to be backed right off to stop it, which is normal behavior for this design."

IIRC even though I used the spec'd transistors I needed to adjust this value as well.

_________________
-Jim
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 [2 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