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SITE WEB Électronique et Radio-amateur
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Jacques Audet VE2AZX
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Electronics and Amateur Radio WEB SITE
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SITE WEB Électronique et Radio-amateur
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Jacques Audet VE2AZX
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Electronics and Amateur Radio WEB SITE
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Notre site de VOYAGES Commentaires ? Questions ? Écrivez moi !
Documents en français Equipments et pièces à vendre SERVICES TECHNIQUES
Présentation sur les Baluns et Ferrites Pourquoi utiliser un balun - Types de Baluns: courant et voltage - Comment les vérifier - Vérifiez votre balun et vos ferrites avec votre analyseur SWR. Utilisations de ferrites sur le feeder et sur les conducteurs environnants. Et plus encore ...
Quiz sur les antennes et lignes de transmission Concepts de base, paramètres des lignes de transmission - Mesure de l'impédance - Utilisation d'un analyseur SWR - Pourquoi un câble coaxial ayant un conducteur central #12 a-t-il plus plus de pertes qu’une ligne parallèle utilisant un conducteur #16 ? - Combien y a-t-il de conducteurs indépendants pour le RF dans un câble coaxial ? Qu’est-ce qu’un antenna tuner ? - La puissance réfléchie vers le TX par l’antenne est-elle de la puissance perdue ? Un SWR élevé dans une ligne balancée ne causera pas de radiation à partir de la ligne…, vrai ou faux ? Un faible taux d'onde stationnaire est la preuve qu'un système d'antenne fonctionne bien et est efficace, vrai ou faux ? Et plus encore ...
Schéma de la sonde courant MFJ-206 Cette sonde permet de mesurer facilement les courants circulant sur le blindage du câble coaxial et sur les conducteurs de l'antenne.
Antenne verticale portative 75 - 40 mètres Cette antenne possède une bonne efficacité et est facile à monter/démonter. Hauteur: 28 pi. Utilise 3 radiales surélevées.
Utilisation de STUBS coaxiaux pour atténuer les signaux provenant d'autres bandes Techniques utiles en HF durant le field day !
Shunts Fabriqués avec des Conducteurs Standard Utilisez les câbles d'alimentation pour mesurer le courant.
Variac et Wattmètre 60 Hz - Voltmètre - Ampèremètre Lectures numériques et monitoring des formes d'onde du voltage et du courant sur un oscilloscope.
Variac et Wattmètre 60 Hz - Schéma
English Documents Equipments and Parts for Sale
Comments ? Questions ? Email me !
Baluns and Ferrites
Baluns and Ferrites Presentation Reasons for using a balun - Balun types - How to check your balun an ferrites with a SWR analyzer - Using ferrites on your feeder and nearby conductors and more ...
Common-Mode Chokes by Chuck W1HIS This complements my document on baluns and ferrites.
Check your Ferrites with your SWR Analyzer Describe an easy to build a very simple fixture that allows you to verify the effective impedance of ferrite cores.
MFJ-206 Current Probe Schematic This magnetic probe allows quick relative measurements of RF currents on the outer shield of a coax cable and antenna elements.
Amidon Ferrites - Inductance and # Turns Calculator Excel spreadsheet calculates the low frequency inductance and # turns for Amidon parts.
Transmission Line Stuff - Q Factor
Measure Cable Zo with an SWR Analyzer A simple technique that allows measuring cable Zo from 50 up to about 100 ohms
Coaxial Cable Delay - Theory Why is the delay changing over frequency ?
Coaxial Cable Delay Measurements Reports on delay measurements show that coaxial cables are not all the same.
QEX Article Sept/Oct 2006: Q Calculations of L-C Circuits and Transmission Lines: A Unified Approach Calculate the Q factor of any circuit based on its complex impedance data. These computations allow easy simulation and optimization of stub resonators. They apply to RLC circuits, transmission lines and antennas.
Get the Files Related to the above QEX Article (Select 9x06 Audet.zip) From the ARRL web site.
Calculate Losses, Dielectric Loss Tangent, Q factor for short lines and quarter wavelength lines An Excel spreadshet does these computations for open and shorted lines, for common coaxial cables.
Calculate the Equivalent Q Factor of Cascaded Resonators Applies to a pair of resonators on the same frequency. Excel spreadsheet.
Q Factor Measurements with an SWR Meter The author reviews existing techniques and proposes a simpler method that uses an SWR analyzer along with a spreadsheet that easily computes the unloaded Q. Published in QEX jan. 2012.
Coaxial Cable Currents In this paper I analyze and measure coaxial lines when subjected to currents on the outer shield. The analysis may be done with simple models, no black magic being necessary. A lab grade VNA is used to precisely measure SWR and attenuation.
Use 75 ohm Hardline in a 50 ohm System Describes how to build L-C transformers at both ends of the line.
Make your Own Custom Impedance Coax Shows how to make 125 ohm coax for use in quarter wave matching of folded dipoles au VHF.
Calculate Line Length based on Degrees Calculate the actual transmission line length when the length is given in degrees.
Antennas
Portable
Vertical Antenna for 40m and 75m It
uses elevated radials and an umbrella that serves as a capacitive hat to cover the 75m
and 40m bands.
Modeling results are also shown as well as measured data compared to a standard car rooftop vertical.
Variations in the basic design are explored with actual component values shown.
Additional Info on the Portable Vertical Antenna (new) Tuner construction, antenna assembly procedure and more pictures.
Excel Spreadsheet eases Designing L-C Traps Useful to resonate an antenna at two frequencies above and below the self resonant frequency. Requires two measurements.
Frequency Standards - Measurements
Off the Air Frequency Measurements FMT Shows how to use Spectrum Lab software for precise frequency measurements, My set-up and examples of an Excel file to process the measurements. Describes some of the hardware that I use.
Modifications and Analysis of VE2ZAZ Frequency Standard Also describes my own implementation of VE2ZAZ frequency standard in the HP 5328A counter.
HP 10544A OCXO as used in HP 5328 Counter, Data Sheet and Schematic
My new 10 MHz GPS Frequency Standard using an MV89A OCXO and Clock Distribution (updated) Shows the electrical and mechanical design as well as test results on my new GPS frequency standard, using the VE2ZAZ controller. Also shows my outdoor GPS antenna.
Clock Stability Testing Stability comparisons of 10 MHz clocks: HP 10544A - HP 8924C – MV89A - HP 10811A - SMHU sig gen. Measurements are short term stability, with readings every second.
Filter / Duplexer Stuff
Theory and Testing of Duplexers What you always wanted to know about duplexers.
Coupling Loops for Duplexers Shows the influence of different loop shapes on the insertion loss.
RepeaterSensitivity - De-Sense Tests Testing RX sensitivity degradations caused by antenna noise pick-up and TX signal feeding back into RX. Build a high performance signal sampler. GE Master II front end helical filter measured response.
Narrow Band Crystal Notcher A Simple Circuit for making phase noise measurements.
HP 5253 Frequency Converter makes a High Q VHF Bandpass Filter Tunes 50 to 500 MHz, easy to modify.
HP 5254 Frequency Converter makes a High Q UHF Bandpass Filter and Harmonic Generator Tunes 300 to 3000 MHz, easy to modify. Low noise harmonic generator.
HF L/C Bandpass Filters Two simple circuits using a single variable capacitor.
Hi-Q Variable Audio Filter (900-1100 Hz, 5 Hz wide) This bandpass amplifier / filter uses an op-amp to provide 40 dB gain. It is based on the Hall network.
R-L-C Circuits and Crystals Measurements
Measure and Calculate the Q and Bandwidth of R L C Series/Parallel Resonant Circuits with only 3 Attenuation Measurements Excel spreadsheet.
Measure and Calculate Crystal Parameters with 3 Attenuation Measurements. Similar to above Excel Spreadsheet. Allows VNA attenuation data (S21) to be used. Shows the shunt type fixture that I use.
S11 Data Converter Excel Spreadshet converts complex reflection coefficient data to Return Loss, Real and Imaginary components and equivalent L or C values. Also provides plots. (updated) Added return loss calculations based on a user specified impedance.
Measure Complex Impedances from 0.01 ohms to 100 K ohms with your VNA. This Excel spreadsheet uses S21 Real and Imaginary Parameters. Measurements are done in series and shunt configurations, over the frequency range in use.
OTHER
60 Hz Line Voltage Limiter uses a GFI (Ground Fault Interrupter) Basic article published in Electronic Design, June 2011. Prevent long duration line overvoltages from damaging your equipment. Note that varistors as used in common surge protection devices can only suppress short duration voltage transients.
Line Voltage Limiter - Additional Info
Variac and 60 Hz Wattmeter - Voltmeter - Ammeter Provides digital readings and allows monitoring voltage and current waveforms on a scope.
Variac and 60 Hz Wattmeter - Voltmeter - Ammeter - Schematic
Easily Made Current Shunts Using Existing Conductors Use your equipment cables as current shunts.
Repair of HP Programmable attenuators (from Lothar Baier and myself)
HP 8753D VNA Save Waveforms and Measured Data - The easy way
Noise Figure testing (updated) Excel Spreadsheet. Use your spectrum analyzer or suitable amplifiers/detector to measure noise figure. Based on Agilent Application Note 57-2 - Noise Figure Measurement Accuracy – The Y-Factor Method http://cp.literature.agilent.com/litweb/pdf/5952-3706E.pdf
AADE L-C Meter Probing at the end of a coax cable: What are the limitations ? Graphs show the effect of a one foot length of RG-174 when measuring L and C's. Also shows my home made SMT component probe.
Wideband Return Loss Bridges - Construction and Tests (updated) Three models shown, covering below 20 KHz to greater than 2000 MHz, along with test results.
Upgrading BOONTON models 92/42 RF Voltmeters Replace the mechanical chopper and AC amps with chopper stabilized low offset op amps.
Schematics of Boonton RF Probes (new) As used in Boonton RF voltmeters and power meters.
Build your own wideband RF Sampler (new) Resistive sampler covers DC to 2 GHz.
Useful Links
AC6LA Dan Maguire Excellent transmission line software: TLDetails and others.
KE5FX Web Site KE5FX Web Site Interesting GPIB Software and Time-Frequency Measurements
DL4YHF Audio Spectrum Analyzer Software - Spectrum Lab
Visits since August 28 2012
