Laser pointer discussion. Read/write reviews of laser pointers and laser pointer companies. Learn about all types of laser pointers and lasers





Welcome to Laser Pointer Forums! If you are looking for a laser pointer or want to compare different laser pointer companies, you may want to check out the LPF Laser Pointer Company Database. The link will open in a new window for your convenience.








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes
Laser Technology Laser Pointer Parts Lasers by Wavelength
Top 10 Laser Pointer Companies Laser Pointer Company Database Visible Beam Laser Pointers


One laser store meets all your needs

























Go Back   Laser Pointer Forums - Discuss Laser Pointers > Lasers > Tutorials, Help & Repairs



LPF List of Laser Pointer Companies (link opens new window)



Reply
 
LinkBack Thread Tools Display Modes
Old 05-16-2011, 11:55 PM #1
Class 1M Laser
 
Join Date: Apr 2011
Location: A random place in north dakota.
Posts: 213
Rep Power: 20
random person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud of
random person random person is offline
Class 1M Laser
 
Join Date: Apr 2011
Location: A random place in north dakota.
Posts: 213
Rep Power: 20
random person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud ofrandom person has much to be proud of
Default Oscilator with Freq+duty cycle control?

So I've managed to build a current source that is PWM-ible to about 500khz+ at 2A+. Now i'm just looking at building a Frequency source where I can change both the frequency and the duty cycle independently of each other. Most relaxation oscillators only have a 50% duty cycle and with 555 timers the frequency and the duty cycle are related. Anyone know how to build easy frequency source that can adjust the duty cycle and the frequency independently of each other?


__________________


random person is offline   Reply With Quote







LPF List of Laser Pointer Companies (link opens new window)







Old 05-17-2011, 12:06 AM #2
Benm's Avatar
Class 4 Laser
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,442
Rep Power: 18962
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Benm Benm is online now
Class 4 Laser
Benm's Avatar
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,442
Rep Power: 18962
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Default Re: Oscilator with Freq+duty cycle control?

You can build something like that using two 555s, or a 556. The first part will act like a normal oscillator. The second one will act as a pulse length corrector. This way, you can set the frequency with the first oscillator, and then adjust the pulse width with the second.
Benm is online now   Reply With Quote
Old 05-17-2011, 05:19 PM #3
123splat's Avatar
Class 2 Laser
 
Join Date: Jan 2011
Posts: 428
Rep Power: 59
123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute
123splat 123splat is offline
Class 2 Laser
123splat's Avatar
 
Join Date: Jan 2011
Posts: 428
Rep Power: 59
123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute123splat has a reputation beyond repute
Default Re: Oscilator with Freq+duty cycle control?

read the National Semi specs on the 555, or try an Exar 8038....
123splat is offline   Reply With Quote
Old 05-17-2011, 11:21 PM #4
GBD GBD is offline
Banned
 
Join Date: Oct 2010
Posts: 805
Rep Power: 0
GBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond repute
GBD GBD is offline
Banned
 
Join Date: Oct 2010
Posts: 805
Rep Power: 0
GBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond reputeGBD has a reputation beyond repute
Default Re: Oscilator with Freq+duty cycle control?

Heres an oscillator Ive used a couple of times, it will do as Benm described:
Ive just used an LM556 for the ease of a single 14-DIP package.



The first part of the time is just a variable frequency oscillator (50% duty) and it just feeds the trigger of the other 555, which can be adjusted for duty independantly (0-50)

Last edited by GBD; 05-18-2011 at 12:34 AM.
GBD is offline   Reply With Quote
Old 05-18-2011, 12:25 AM #5
Meatball's Avatar
Class 3B Laser
 
Join Date: Feb 2008
Location: Lincoln, NE
Posts: 2,989
Rep Power: 242
Meatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond repute
Meatball Meatball is offline
Class 3B Laser
Meatball's Avatar
 
Join Date: Feb 2008
Location: Lincoln, NE
Posts: 2,989
Rep Power: 242
Meatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond reputeMeatball has a reputation beyond repute
Default Re: Oscilator with Freq+duty cycle control?

I actually have a pcb ready to go to build such a device. Its uses two 555 timers to interrupt a DRSSTC tesla coil. If you want the PCB, let me know and I'll see if I can't find it somewhere. I'm in the middle of moving so we'll see how that goes!

With this pcb, you can individually control pulsewidth, and pulse repetition frequency.

Here is the schematic:


Here is the circuit for MULTISIM users:

Download, and then change the file type to .ms11

KEEP IN MIND, that the passive component values are set for HIGH frequencies. You will have to adjust them to match what range of frequencies you are looking for.
Attached Files
File Type: avi DRSSTC Modulator.avi (333.6 KB, 103 views)
__________________
FIAT LUX

(\__/)
(='.'=)
(")_(")
Meatball is offline   Reply With Quote
Old 05-18-2011, 01:18 AM #6
Cyparagon's Avatar
Class 4 Laser
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,144
Rep Power: 9321
Cyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond repute
Cyparagon Cyparagon is online now
Class 4 Laser
Cyparagon's Avatar
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,144
Rep Power: 9321
Cyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond repute
Default Re: Oscilator with Freq+duty cycle control?

I think those 0.1F should be 100000pF and the 10000pF should be 0.01F.

Otherwise, cool!
__________________
A problem well stated is a problem half solved.
Cyparagon is online now   Reply With Quote
Old 05-18-2011, 10:26 AM #7
HIMNL9's Avatar
Class 4 Laser
 
Join Date: May 2009
Location: Lost somewhere in the EU mess ;)
Posts: 5,416
Rep Power: 404
HIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond repute
HIMNL9 HIMNL9 is offline
Class 4 Laser
HIMNL9's Avatar
 
Join Date: May 2009
Location: Lost somewhere in the EU mess ;)
Posts: 5,416
Rep Power: 404
HIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond repute
Default Re: Oscilator with Freq+duty cycle control?

You can probably use a single 555 with a "dirty trick", but this depend from what precision you need ..... with a single 555, you can change some duty-cycle AND frequency, but frequency changes only in a reduced range, and duty-cycle cannot go over 10-to-90 % range .....



EDIT: like this one: (damn coreldraw is not the better program for draw circuits )

__________________
High Impulse Multipath Neutron Laser (mark 9 ) (LOL)
Dare mo mita koto no nai, kaze, kumo, suna, umi ..... Kokoro no hate no doko ka eien ga kagayaku.

Last edited by HIMNL9; 05-18-2011 at 02:46 PM.
HIMNL9 is offline   Reply With Quote
Reply





Thread Tools
Display Modes

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 On
Pingbacks are On
Refbacks are On











Loading








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes






Privacy Policy | Advertising Disclaimer | Terms of Use


 


All times are GMT. The time now is 03:47 PM.


Powered by: vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO
Privacy Policy | Advertising Disclaimer | Terms of Use
Copyright (C) 2017 Laser Pointer Forums, LLC