If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #3114
Joined: Sat Aug 14 2010, 08:33AM
Location:
Posts: 608
I CANNOT find anything. I dont know enough about logic ic's to find much of anything, Countless hours spent searching.
Goal:
Need a very stable 4Mhz square wave.
Feed crystal oscillator output into logic ic get square wave out... Does anyone know what chip i would beed to achieve that ? Would i need a buffer before? I plan on feeding the signal source into this intern to switch a MOSFET
Registered Member #3114
Joined: Sat Aug 14 2010, 08:33AM
Location:
Posts: 608
Sulaiman wrote ...
why not use a crystal oscillator? e.g.
Thats what I want to do since I need the accuracy the crystal supplies. Maybe I dont fully know what that crystal you linked does... Do I supply a voltage and It generates 4MHz? Doesn't it need to be buffered before going into the gate drive or at least amplified ?
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140
The crystal oscillator that I linked to is a 3.3 v supply version, not a good choice to drive the gate driver ICs a 5v squarewave output crystal oscillator is more suitable, e.g.
Registered Member #2099
Joined: Wed Apr 29 2009, 12:22AM
Location: Los Altos, California
Posts: 1714
jdub's circuit is for using a bare 2-terminal crystal (passive component). Change the crystal to change the frequency. Sulaiman pointed to some crystal oscillator components, which are easier to use. Connect appropriate power voltage (3.3 or 5 volts) and get a corresponding logic signal out. In both cases the frequency is fixed. Worst case frequency error of +/- 100 ppm (0.01%) is a pretty loose tolerance for crystal controlled oscillators.
Your 74LS624 is a voltage controlled oscillator chip. VCO, not VCXO. No crystal, and you can tune the frequency over a substantial range. How are you planning to measure the frequency, if you don't have an oscilloscope? You could divide it down into the audible range (e.g. with one CD4040 or CD4060) and listen with headphones or a small loudspeaker. Instrument-tuning apps on smartphones can convert a tone into a number. Or adapt an old auto service dwellmeter/tachometer, which I could send you for cost of postage.
It's time you learned more about logic IC's. Jump on in; they don't bite. Get a plug-in breadboard to play with -- apparently as popular now as they were decades ago. There are other forums to learn at. Logic signal input/output compatibility can be checked by studying the DC specifications section of the data sheets. Before the Internet, people used to keep things called data books for that purpose.
Registered Member #3114
Joined: Sat Aug 14 2010, 08:33AM
Location:
Posts: 608
klugesmith wrote ...
jdub's circuit is for using a bare 2-terminal crystal (passive component). Change the crystal to change the frequency. Sulaiman pointed to some crystal oscillator components, which are easier to use. Connect appropriate power voltage (3.3 or 5 volts) and get a corresponding logic signal out. In both cases the frequency is fixed. Worst case frequency error of +/- 100 ppm (0.01%) is a pretty loose tolerance for crystal controlled oscillators.
Your 74LS624 is a voltage controlled oscillator chip. VCO, not VCXO. No crystal, and you can tune the frequency over a substantial range. How are you planning to measure the frequency, if you don't have an oscilloscope? You could divide it down into the audible range (e.g. with one CD4040 or CD4060) and listen with headphones or a small loudspeaker. Instrument-tuning apps on smartphones can convert a tone into a number. Or adapt an old auto service dwellmeter/tachometer, which I could send you for cost of postage.
It's time you learned more about logic IC's. Jump on in; they don't bite. Get a plug-in breadboard to play with -- apparently as popular now as they were decades ago. There are other forums to learn at. Logic signal input/output compatibility can be checked by studying the DC specifications section of the data sheets. Before the Internet, people used to keep things called data books for that purpose.
Man this place has really gone down hill and you are a perfect example. Frist of all I do own a scope! secondly, I am over my head and I dont know very much about any of this class e RF amps but thats how you learn new things and this is a place to ask quesions. Im challanging myself and come here for support and this is what I get "Get a plug-in breadboard to play with -- apparently as popular now as they were decades ago. There are other forums to learn at." are you kidding me ?!?!
I have looked at the data sheets for the provided schematics and I have been doing a ton of research but I am by know means an expert.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
4Mhz square wave generator
