Shared Top Border with GlobalSpec Ad

Electronic Circuits and electronic circuits, electronic schematics plus an extensive resource for hobbyists, inventors and engineers

DiscoverCircuits.com, has 35,000+ electronic circuits, cross-referenced
into 500+ categories.    We have searched the web to help you find quick design ideas.
We make every effort to link to material posted by the designer. 
Please let us if you would like us to link to or post your design.

HOME Schematic Lists Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches

 
Timers and Counters Circuits, Page 1
Timers & Counters:  #-A     B-E    F-L     M-S     T-Z
Last Updated on: Friday, October 03, 2014 10:38 AM
Circuits Designed by Dave Johnson, P.E. :
  • 3 Minute Closet Light #2
    I have a coat closet by my front door.  The thing is very dark at night and really needs some kind of illumination inside.  I could hire an electrician to install a light in the closet ceiling and then wire it to a toggle switch outside the door but that would cost me quite a bit of money.  That doesn’t sound like a good investment for something which does not get much use.  I looked around for some battery powered LED lights which would emit enough light for the small space and I found one made by Sylvania....

  • 555 Timer Forms Simple PWM Motor Controller
    Using a CMOS version of the 555 timer, this circuit can be used to control the speed of a motor by adjusting the duty cycle of the pulses sent to the motor. (added 7/06)

Links to electronic circuits, electronic schematics, designs for engineers, hobbyists, students & inventors:
Consulting Services include:
  • Applications Engineering
  • Design & Development
  • Electronic Circuit Design
  • Custom Test Fixtures

    (Minimum Fee $400.00)
806-368-7747 or
http://www.djandassoc.com/
12v to 240v Inverter -  This circuit will produce 240v at 50Hz. The wattage will depend on the driver transistors and transformer. 
3 Position Servo Driver Circuit (LM555) -  This circuit uses an SPDT toggle switch to select One-of-Three positions for a servo motor….Scroll down to find this design….Circuit for model railroad trains…. [from Rob Paisley's Model Train web site]
5 Times Around Circuit -  The 5 Times Around circuit was designed to automatically let an N Scale locomotive and car travel around a loop 5 times and stop for approximately a minute and then repeat the cycle. [from Rob Paisley's Model Train web site]
50% Output Duty Cycle (Fixed) Using Logic Devices -  Uses the LM555 timer or its cousins with other letter prefixes. There can be minor differences between 555 timer IC's from different manufacturers but they all should be useable for any circuit.   Designed for Model Trains…. [from Rob Paisley's Model Train web site]
50% Output Duty Cycle (Variable) -  Uses the LM555 timer or its cousins with other letter prefixes. There can be minor differences between 555 timer IC's from different manufacturers but they all should be useable for any circuit.   Designed for Model Trains…. [from Rob Paisley's Model Train web site]
555 Amplifier -  The 555 can be used as an amplifier. It operates very similar to pulse-width modulation. The component values cause the 555 to oscillate at approx 66kHz and the speaker does not respond to this high frequency.  Instead it responds to the average CD value of the modulated output and demonstrates the concept of pulse-width modulation. The chip gets very hot and is only for brief demonstrations. 
555 Timer Current Draws -  Uses the LM555 timer or its cousins with other letter prefixes. There can be minor differences between 555 timer IC's from different manufacturers but they all should be useable for any circuit.   Designed for Model Trains…. [from Rob Paisley's Model Train web site]

555 Timer Output Section -  Uses the LM555 timer or its cousins with other letter prefixes. There can be minor differences between 555 timer IC's from different manufacturers but they all should be useable for any circuit.   Designed for Model Trains…. [from Rob Paisley's Model Train web site]
555 VCO -  By adjusting the voltage on pin 5, (the CONTROL pin) the frequency of the oscillator can be adjusted quite considerably.
6 Aspect - Searchlight Signal Driver (LM555) -  The circuit on this page is a 6 Aspect driver for a bicolour LED type Searchlight Signal. The available signal indications are; SOLID - RED, YELLOW, GREEN, and FLASHING - RED, YELLOW and GREEN. The circuit can also turn the signal OFF for approach lighting if desired. [from Rob Paisley's Model Train web site]
Active High Trigger -  This circuit produces a HIGH output via a HIGH trigger:
Active Low Trigger -  This circuit sits LOW and the output goes HIGH when the push-button is pressed. When the normally-closed push button is pressed, it opens and the uncharged 1u will be pulled to nearly 0v rail via the 10k and this will take pin 2 LOW to make output pin 3 HIGH for the duration determined by the 22u and 100k. If the push-switch stays open, the 1u will charge via the 100k and eventually the output of the 555 will go low....
Adjustable Timer -  This circuit starts timing when switched on. A green LED lights to show that timing is in progress. When the time period is over the green LED turns off, a red LED turns on and a bleeper sounds. The time period is set by a variable resistor and it can be adjusted from 1 to 10 minutes (approximately). It could be used to set a time limit when playing games or as an egg-timer in the kitchen.... [Designed by John Hewes]
Advanced Circuits For The LM555 Timer -  Uses the LM555 timer or its cousins with other letter prefixes. There can be minor differences between 555 timer IC's from different manufacturers but they all should be useable for any circuit.   Designed for Model Trains…. [from Rob Paisley's Model Train web site]
Astable Multivibrator -  The capacitor C charges via R1 and R2 and when the voltage on the capacitor reaches 2/3 of the supply, pin 6 detects this and pin 7 connects to 0v. The capacitor discharges through R2 until its voltage is 1/3 of the supply and pin 2 detects this and turns off pin 7 to repeat the cycle....
Automatic Curtain Closer -  This circuit uses a mixture of transistors, an IC and a relay and is used to automatically open and close a pair of curtains. Using switch S3 also allows manual control, allowing curtains to be left only partially open or closed. The circuit controls a motor that is attached to a simple pulley mechanism, to move the curtains....
Average 51.5 % Output Duty Cycle Using A 555 Timer -  Uses the LM555 timer or its cousins with other letter prefixes. There can be minor differences between 555 timer IC's from different manufacturers but they all should be useable for any circuit.   Designed for Model Trains…. [from Rob Paisley's Model Train web site]

Timers & Counters:  #-A     B-E    F-L     M-S     T-Z


 Linking is ALLOWED but COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED.

HOME Schematic Lists Hobby Corner Dave's Circuits Electronic Resources Contact Info

 

 About Us   |  Advertise on DiscoverCircuits.com   |   Report Broken Links  |    Link to DiscoverCircuits.com  |    Privacy Policy

Copyright  2002 - 2014 David A. Johnson & Associates.  All Rights reserved.