Electronics World Cover,TOC,and list of posted Popular Electronics articles QST Radio & TV News Radio-Craft Radio-Electronics Short Wave Craft Wireless World About RF Cafe RF Cafe Homepage RF Cafe in Morse Code Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs Twitter LinkedIn Crosswords Engineering Humor Kirt's Cogitations Engineering Event Calendar RF Engineering Quizzes AN/MPN-14 Radar 5CCG Notable Quotes App Notes Calculators Education Magazines Software,T-Shirts,Coffee Mugs Articles - submitted by RF Cafe visitors Simulators Technical Writings RF Cafe Archives Test Notes Wireless System Designer RF Stencils for Visio Shapes for Word Search RF Cafe Sitemap Advertising Facebook RF Cafe Forums Thank you for visiting RF Cafe!

Noise at Resonance Frequency - RF Cafe Forums

The original RF Cafe Forums were shut down in late 2012 due to maintenance issues. Original posts:

Amateur Radio | Antennas | Circuits & Components | Systems | Test & Measurement


Guest
Post subject: Noise at resonance frequency Posted: Mon Sep 26, 2005 11:27 am
I have build a VCO for a mixer IC. When i am viewing the output power of VCO with Spectrum analyzer then there is a lot of noise at and around desired resonance frequency. I am using a DC supply of +- 5V and a regulated supply from 0V to 1.5V to check the response of VCO resonance frequency. Noise is less when i am operating with 0V or 1.5V regulated voltage, but if i give around 0.7V of regulated supply then noise gets worse. I have also tried connecting capacitors with my regulated supply but to no improvement. Can anybody please suggest that how can i get rid of the noise ?


Top

guest
Post subject: VCO noisePosted: Wed Sep 28, 2005 3:13 pm
I'm a bit confused. Do I understand that you are running the oscillator proper from +/- 5V regulated, and that you're changing the control voltage (from a different supply?) from 0 to 1.5V?

If your VCO uses a varactor diode, you need to make sure that it's never forward biased. That means avoiding the range of 0 to at least 0.7 V

Good Luck!



Posted  11/12/2012

RF Cafe Software

   Wireless System Designer - RF Cafe
Wireless System Designer

RF & EE Symbols Word
RF Stencils for Visio
Calculator Workbook
RF Workbench
Smith Chartâ„¢ for Visio
Smith Chartâ„¢ for Excel

About RF Cafe

Kirt Blattenberger - RF Cafe WebmasterCopyright
1996 - 2022
Webmaster:
Kirt Blattenberger,
 BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:
 AirplanesAndRockets.com

Try Using SEARCH
to Find What You Need. 
There are 1,000s of Pages Indexed on RF Cafe !

height-line