Go Back   Home > Forums > General Interest > Everything Else

Everything Else Anything related to audio / video / electronics etc) BUT remember- we have many new forums where your thread may now fit! .... Parts, Equipment & Tools, Construction Tips, Software Tools......

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 16th June 2009, 05:18 AM   #1
xyz9915 is offline xyz9915  Pakistan
diyAudio Member
 
Join Date: Apr 2007
Default LM555 as variable frequency oscillator

Hello!
I need a circuit in which the frequency of LM555 astable multivibrator can be controlled externally I mean by the help of transistor etc. So, please guide what modification may be done in the attached circuit
Attached Images
File Type: jpg lm555.jpg (16.5 KB, 58 views)
  Reply With Quote
Old 17th June 2009, 12:10 PM   #2
bwaslo is offline bwaslo  United States
diyAudio Member
 
bwaslo's Avatar
 
Join Date: May 2006
Location: Cinciinati, OH
Look into replacing resistors with something like MCP4012.

If you want voltage control, don't use a 555, use a CD4046/74HC4046, a better chip for a variable oscillator, anyway. Use 555 only if you need to vary duty cycle. For most audio uses you'll want 50% duty cycle and something like the 4046 is more appropriate and has more versatile control.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Variable frequency active crossover FrankDIY Solid State 22 4th July 2009 03:30 PM
High frequency high voltage oscillator - help! gentlevoice Analog Line Level 8 10th September 2008 02:52 PM
Variable feedback to enhance damping factor at low frequency svokke Tubes / Valves 8 7th June 2007 04:14 PM
Variable center frequency filter metal Solid State 26 18th November 2005 08:12 AM
Variable frequency low pass filter pk386 Chip Amps 11 25th September 2004 01:43 PM


New To Site? Need Help?

All times are GMT. The time now is 07:55 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2