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
Simple Offset/gain Circuit Schematic.
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
Dave Kendall



Joined: May 26, 2007
Posts: 421
Location: England
Audio files: 3

PostPosted: Mon Jun 08, 2009 2:15 pm    Post subject: Simple Offset/gain Circuit Schematic.
Subject description: Basic, but useful.....
Reply with quote  Mark this post and the followings unread

Hi all.

Here's a dead-simple circuit I use all the time when tweaking circuits, and it is a useful module in its own right.

If built with both OFFSET and GAIN as centre detent pots, with both pots at 12 o'clock, there is no gain or offset - the signal, CV or audio goes straight through unchanged. The max gain with this circuit is 2X. It could easily be made more, by increasing the 200K resistor, but the pot would no longer be at unity gain at 12 o'clock.

The second pic shows how to convert Ken Stone's CGS04 mixer PCB, for those who don't like perfboard.
The trimmer version is useful for turning a 0V, +5V, +10V PITCH BEND CV from a midi to CV converter into a -5V, 0V, +5V output. (i.e. centred)
If using it for this, connecting the outer pins of the OFFSET trimmer to -Ve and GND gives more control range from the trimmer (because it needs to go negative anyway, so the trimmer only covers a span of 15V, rather than 30V.

If you're really enthusiastic, you could try wiring a resistor in series with each outer pin going to-Ve and GND, and use a smaller value trimmer. This would give even finer control.
Hope this is as useful to people as it has been for me. Smile


cheers,
Dave


Offset scaler Schemo.jpg
 Description:
 Filesize:  187.77 KB
 Viewed:  594 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

Offset scaler Schemo.jpg


Back to top
View user's profile Send private message
synthmonger



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

PostPosted: Mon Jun 08, 2009 3:43 pm    Post subject: Reply with quote  Mark this post and the followings unread

No 2nd pic?
_________________
Youtube!
modular demos!
Whacky tunes!
Back to top
View user's profile Send private message Visit poster's website
Dave Kendall



Joined: May 26, 2007
Posts: 421
Location: England
Audio files: 3

PostPosted: Mon Jun 08, 2009 11:15 pm    Post subject: Reply with quote  Mark this post and the followings unread

Embarassed

here it is...

cheers,
Dave

(edited to actually include the pic Smile )


CGS04.jpg
 Description:
 Filesize:  1.67 MB
 Viewed:  746 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

CGS04.jpg



Last edited by Dave Kendall on Mon Jun 08, 2009 11:39 pm; edited 1 time in total
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


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