http://vk1od.net VK1OD on the 'net news en-us webmaster@vk1od.net (webmaster) webmaster@vk1od.net (webmaster) Owen Duffy http://vk1od.net http://www.vk1od.net/Vk1odOnTheNet.jpg 137.7kHz QRSS on one chip (revised 3/2/12) Fri, 03 Feb 2012 00:00:00 +0000 http://vk1od.net/module/137.700Beacon/index.htm http://vk1od.net/module/137.700Beacon/index.htm-03/02/12 Transmitters Improving weak signal identification of FSK beacons Fri, 03 Feb 2012 00:00:00 +0000 http://vk1od.net/module/smbk/dual.htm http://vk1od.net/module/smbk/dual.htm-03/02/12 Equipment Simple Morse beacon keyer Fri, 03 Feb 2012 00:00:00 +0000 http://vk1od.net/module/smbk/index.htm http://vk1od.net/module/smbk/index.htm-03/02/12 Equipment Effective Radiated Power (ERP) Tue, 17 Jan 2012 00:00:00 +0000 http://vk1od.net/antenna/concepts/erp.htm http://vk1od.net/antenna/concepts/erp.htm-17/01/12 Antennas Jaycar MI5104 inverter Mon, 16 Jan 2012 00:00:00 +0000 http://vk1od.net/hardware/MI5104/index.htm http://vk1od.net/hardware/MI5104/index.htm-16/01/12 Equipment DTR / RTS interface unit Sun, 15 Jan 2012 00:00:00 +0000 http://vk1od.net/module/DtrRtsInterface/index.htm http://vk1od.net/module/DtrRtsInterface/index.htm-15/01/12 Equipment Insertion Loss vs Transmission Loss Sun, 15 Jan 2012 00:00:00 +0000 http://vk1od.net/transmissionline/concept/iltl.htm http://vk1od.net/transmissionline/concept/iltl.htm-15/01/12 Transmission Lines Adjusting a loaded HF vertical Fri, 13 Jan 2012 00:00:00 +0000 http://vk1od.net/antenna/m40/alhfv.htm http://vk1od.net/antenna/m40/alhfv.htm-13/01/12 Antennas PllLdr application - AD9850/51 300Bd FSK Sun, 08 Jan 2012 00:00:00 +0000 http://vk1od.net/module/PllLdr/cs02/index.htm http://vk1od.net/module/PllLdr/cs02/index.htm-08/01/12 Equipment ZL1AN's transmission line challenge Mon, 09 Jan 2012 00:00:00 +0000 http://vk1od.net/transmissionline/ZL1AN/tlp1.htm http://vk1od.net/transmissionline/ZL1AN/tlp1.htm-09/01/12 Transmission Lines Setup of an FM AFSK transmitter Fri, 06 Jan 2012 00:00:00 +0000 http://vk1od.net/FM/AfskFmSetup/index.htm http://vk1od.net/FM/AfskFmSetup/index.htm-06/01/12 Transmitters APRS AFSK on VHF Wed, 04 Jan 2012 00:00:00 +0000 http://vk1od.net/FM/VhfAprs/index.htm http://vk1od.net/FM/VhfAprs/index.htm-04/01/12 Transmitters PllLdr application - AD9850 Wed, 28 Dec 2011 00:00:00 +0000 http://vk1od.net/module/PllLdr/cs01/index.htm http://vk1od.net/module/PllLdr/cs01/index.htm-28/12/11 Equipment Is the 133' centre fed multiband dipole a no-brainer Mon, 26 Dec 2011 00:00:00 +0000 http://vk1od.net/antenna/133nobrainer/index.htm http://vk1od.net/antenna/133nobrainer/index.htm-26/12/11 Antennas Calculate Vpk and Irms for given power at complex load Mon, 26 Dec 2011 00:00:00 +0000 http://vk1od.net/calc/tl/p2vi.htm http://vk1od.net/calc/tl/p2vi.htm-26/12/11 Software N0XAS ID-O-Matic - VK1OD implementation Fri, 09 Dec 2011 00:00:00 +0000 http://vk1od.net/equipment/ID-Omatic/index.htm http://vk1od.net/equipment/ID-Omatic/index.htm-09/12/11 Equipment A medium priced generator set from eBay Wed, 07 Dec 2011 00:00:00 +0000 http://vk1od.net/hardware/genset/index.htm http://vk1od.net/hardware/genset/index.htm-07/12/11 Equipment An experimental CPLD based PLL (revised) Sat, 03 Dec 2011 00:00:00 +0000 http://vk1od.net/module/CpldPll/index.htm http://vk1od.net/module/CpldPll/index.htm-03/12/11 Equipment MCU to load PLL configuration registers Fri, 02 Dec 2011 00:00:00 +0000 http://vk1od.net/module/PllLdr/index.htm http://vk1od.net/module/PllLdr/index.htm-02/12/11 Equipment Comment on W5DXP's 2011 coil measurement experiment Fri, 18 Nov 2011 00:00:00 +0000 http://vk1od.net/antenna/W5dxpCoilExp/index.htm http://vk1od.net/antenna/W5dxpCoilExp/index.htm-18/11/11 Antennas Exploitation of NEC's GM card Mon, 14 Nov 2011 00:00:00 +0000 http://vk1od.net/antenna/NEC/NecGm.htm http://vk1od.net/antenna/NEC/NecGm.htm-14/11/11 Antennas T Match efficiency estimator Sat, 12 Nov 2011 00:00:00 +0000 http://vk1od.net/calc/tmee.htm http://vk1od.net/calc/tmee.htm-12/11/11 Software Ambient noise survey, Hackett ACT on 40m, 06/03/2009 Sat, 12 Nov 2011 00:00:00 +0000 http://vk1od.net/software/fsm/cs/03/index.htm http://vk1od.net/software/fsm/cs/03/index.htm-12/11/11 Software PA0KLT Si570 Synthesiser - VK1OD implementation Sat, 12 Nov 2011 00:00:00 +0000 http://vk1od.net/module/PA0KLTSynth/index.htm http://vk1od.net/module/PA0KLTSynth/index.htm-12/11/11 Equipment Matching a 5/8λ vertical Thu, 03 Nov 2011 00:00:00 +0000 http://vk1od.net/antenna/FiveEighth/match.htm http://vk1od.net/antenna/FiveEighth/match.htm-03/11/11 Antennas In pursuit of dipole resonance with an MFJ259B revised Wed, 02 Nov 2011 00:00:00 +0000 http://vk1od.net/antenna/misc/isdr.htm http://vk1od.net/antenna/misc/isdr.htm-02/11/11 Antennas Spotless days around solar cycle transition Nov11 Wed, 02 Nov 2011 00:00:00 +0000 http://vk1od.net/propagation/solar/spotless.htm http://vk1od.net/propagation/solar/spotless.htm-02/11/11 Propagation Is Zs of a HF ham tx typically 50+j0? Sun, 20 Jun 2010 00:00:00 +0000 http://vk1od.net/transmissionline/VSWR/Zs50.htm http://vk1od.net/transmissionline/VSWR/Zs50.htm-20/06/10 Transmitters A test of Zs on an IC7000 Sun, 01 Aug 2010 00:00:00 +0000 http://vk1od.net/transmissionline/VSWR/ZsExp.htm http://vk1od.net/transmissionline/VSWR/ZsExp.htm-01/08/10 Transmitters Link coupling transformation ratio (expanded 29/10/11) Sat, 29 Oct 2011 00:00:00 +0000 http://vk1od.net/tx/concept/lctr.htm http://vk1od.net/tx/concept/lctr.htm-29/10/11 Transmitters Learning models or a poor workman always blames his tools Fri, 28 Oct 2011 00:00:00 +0000 http://vk1od.net/antenna/misc/PoorWorkman.htm http://vk1od.net/antenna/misc/PoorWorkman.htm-28/10/11 Antennas Bootstrap coax traps for antennas (expanded 10/11) Wed, 26 Oct 2011 00:00:00 +0000 http://vk1od.net/antenna/coaxtrap/index.htm http://vk1od.net/antenna/coaxtrap/index.htm-26/10/11 Antennas Differential flux leakage in a Guanella 1:1 balun Wed, 26 Oct 2011 00:00:00 +0000 http://vk1od.net/balun/concept/DiffFlux.htm http://vk1od.net/balun/concept/DiffFlux.htm-26/10/11 Baluns ATLLC Examples Mon, 10 Oct 2011 00:00:00 +0000 http://vk1od.net/calc/tl/atllcEx.htm http://vk1od.net/calc/tl/atllcEx.htm-10/10/11 Software RF Arbitrary Transmission Line Loss Calculator Sun, 09 Oct 2011 00:00:00 +0000 http://vk1od.net/calc/tl/atllc.htm http://vk1od.net/calc/tl/atllc.htm-09/10/11 Software Estimating parameters of two wire transmission lines Fri, 07 Oct 2011 00:00:00 +0000 http://vk1od.net/transmissionline/concept/ephmtwtl.htm http://vk1od.net/transmissionline/concept/ephmtwtl.htm-07/10/11 Transmission Lines Noise bridge measurement case study - Bowral dipole Fri, 07 Oct 2011 00:00:00 +0000 http://vk1od.net/measurement/NoiseBridge/cs02/index.htm http://vk1od.net/measurement/NoiseBridge/cs02/index.htm-07/10/11 Measurement Noise bridge measurement case study - shortened vertical monopole matching Thu, 06 Oct 2011 00:00:00 +0000 http://vk1od.net/measurement/NoiseBridge/cs01/index.htm http://vk1od.net/measurement/NoiseBridge/cs01/index.htm-06/10/11 Measurement Filament Management in Amateur Radio applications Wed, 28 Sep 2011 00:00:00 +0000 http://vk1od.net/tx/FilamentManagement/index.htm http://vk1od.net/tx/FilamentManagement/index.htm-28/09/11 Transmitters Does twisting a two wire open line reduce radiation Fri, 23 Sep 2011 00:00:00 +0000 http://vk1od.net/transmissionline/concept/twistedpairrad.htm http://vk1od.net/transmissionline/concept/twistedpairrad.htm-23/09/11 Transmission Lines Can a balun alter the tuning of an antenna system Tue, 13 Sep 2011 00:00:00 +0000 http://vk1od.net/balun/concept/cm/bz.htm http://vk1od.net/balun/concept/cm/bz.htm-13/09/11 Baluns Spoiling Class B Mon, 12 Sep 2011 00:00:00 +0000 http://vk1od.net/tx/concept/SpoilingClassB.htm http://vk1od.net/tx/concept/SpoilingClassB.htm-12/09/11 Transmitters 440Hz (A4, A440) reference oscillator Sun, 11 Sep 2011 00:00:00 +0000 http://vk1od.net/module/440HzRef/index.htm http://vk1od.net/module/440HzRef/index.htm-11/09/11 Hardware Return Loss Tue, 06 Sep 2011 00:00:00 +0000 http://vk1od.net/transmissionline/VSWR/rl.htm http://vk1od.net/transmissionline/VSWR/rl.htm-06/09/11 Transmission Lines Misunderstanding VSWR misleads Sat, 03 Sep 2011 00:00:00 +0000 http://vk1od.net/transmissionline/VSWR/mvm.htm http://vk1od.net/transmissionline/VSWR/mvm.htm-03/09/11 Transmission Lines G4CQM 50Ω coaxial dipole Fri, 02 Sep 2011 00:00:00 +0000 http://vk1od.net/antenna/G4CQM50Dipole/index.htm http://vk1od.net/antenna/G4CQM50Dipole/index.htm-02/09/11 Antennas Spotless days around solar cycle transition Sep11 Fri, 02 Sep 2011 00:00:00 +0000 http://vk1od.net/propagation/solar/spotless.htm http://vk1od.net/propagation/solar/spotless.htm-02/09/11 Propagation Calculate braid coverage Wed, 31 Aug 2011 00:00:00 +0000 http://vk1od.net/calc/BraidCover.htm http://vk1od.net/calc/BraidCover.htm-31/08/11 Software 137.7kHz oscillator Sun, 28 Aug 2011 00:00:00 +0000 http://vk1od.net/module/137700Osc/index.htm http://vk1od.net/module/137700Osc/index.htm-28/08/11 Transmitters 1kHz reference oscillator Sat, 27 Aug 2011 00:00:00 +0000 http://vk1od.net/module/1kHzRef/index.htm http://vk1od.net/module/1kHzRef/index.htm-27/08/11 Hardware Dipole loaded vertical coax feed line Sat, 13 Aug 2011 00:00:00 +0000 http://vk1od.net/antenna/dlv/index.htm http://vk1od.net/antenna/dlv/index.htm-13/08/11 Antennas Noise Figure Meter (NFM) update - V1.11.0 Wed, 10 Aug 2011 00:00:00 +0000 http://vk1od.net/software/nfm/support.htm http://vk1od.net/software/nfm/support.htm-10/08/11 Software Portable generator sets and RCD protection for Amateur Radio field stations Sun, 07 Aug 2011 00:00:00 +0000 http://vk1od.net/hardware/RCD/index.htm http://vk1od.net/hardware/RCD/index.htm-07/08/11 Hardware QRP2000 Synthesiser Fri, 05 Aug 2011 00:00:00 +0000 http://vk1od.net/hardware/Qrp2000/index.htm http://vk1od.net/hardware/Qrp2000/index.htm-05/08/11 Hardware DHL shipment performance Fri, 05 Aug 2011 00:00:00 +0000 http://vk1od.net/misc/DHL.htm http://vk1od.net/misc/DHL.htm-05/08/11 Miscellaneous Avoiding flashover in baluns and ATUs Tue, 05 Jul 2011 00:00:00 +0000 http://vk1od.net/transmissionline/aev/index.htm http://vk1od.net/transmissionline/aev/index.htm-05/07/11 Transmission Lines RX1 Noise Bridge improvement Wed, 22 Jun 2011 00:00:00 +0000 http://vk1od.net/measurement/NoiseBridge/RX1i.htm http://vk1od.net/measurement/NoiseBridge/RX1i.htm-22/06/11 Measurement Codan 7004 - WSPR 40m Mon, 20 Jun 2011 00:00:00 +0000 http://vk1od.net/rx/Codan7004/index.htm http://vk1od.net/rx/Codan7004/index.htm-20/06/11 Receivers Designing with the GI7BT Tue, 14 Jun 2011 00:00:00 +0000 http://vk1od.net/tx/GI7B/index.htm http://vk1od.net/tx/GI7B/index.htm-14/06/11 Transmitters Convert Vpk-Vrms-dBV-dBu-mW-dBm Sat, 11 Jun 2011 00:00:00 +0000 http://vk1od.net/calc/voltcnv.htm http://vk1od.net/calc/voltcnv.htm-11/06/11 Software Antenna Effective Aperture Sun, 05 Jun 2011 00:00:00 +0000 http://vk1od.net/antenna/concepts/Ae.htm http://vk1od.net/antenna/concepts/Ae.htm-05/06/11 Antennas Measuring RF impedance by the three voltmeter method Sat, 04 Jun 2011 00:00:00 +0000 http://vk1od.net/calc/z3vm.htm http://vk1od.net/calc/z3vm.htm-04/06/11 Measurement Measuring common mode current Mon, 30 May 2011 00:00:00 +0000 http://vk1od.net/measurement/icm/index.htm http://vk1od.net/measurement/icm/index.htm-30/05/11 Measurement Pi coupling a single ended valve RF Power Amplifier Sat, 28 May 2011 00:00:00 +0000 http://vk1od.net/tx/concept/pi.htm http://vk1od.net/tx/concept/pi.htm-28/05/11 Transmitters Calculate RF amplifier pi coupler Sat, 28 May 2011 00:00:00 +0000 http://vk1od.net/calc/pi.htm http://vk1od.net/calc/pi.htm-28/05/11 Software Designing with the GS31B Mon, 23 May 2011 00:00:00 +0000 http://vk1od.net/tx/GS31B/index.htm http://vk1od.net/tx/GS31B/index.htm-23/05/11 Transmitters Calculate initial load line of valve RF amplifier Sun, 22 May 2011 00:00:00 +0000 http://vk1od.net/calc/vlle.htm http://vk1od.net/calc/vlle.htm-22/05/11 Software Bowral 7MHz dipole for local contacts (updated) Sun, 22 May 2011 00:00:00 +0000 http://vk1od.net/antenna/7MDipole/7MDipole02.htm http://vk1od.net/antenna/7MDipole/7MDipole02.htm-22/05/11 Antennas Designing the operating point for a grounded grid Triode Class B RF amplifier Mon, 16 May 2011 00:00:00 +0000 http://vk1od.net/tx/concept/TriodeClassB/index.htm http://vk1od.net/tx/concept/TriodeClassB/index.htm-16/05/11 Transmitters Using my Excel cubic spline interpolation functions Fri, 07 May 2010 00:00:00 +0000 http://vk1od.net/measurement/ucs.htm http://vk1od.net/measurement/ucs.htm-07/05/10 Measurement A perspective on the popular 4:1 Ruthroff balun at the base of a ground mounted untuned multi-band vertical Fri, 06 May 2011 00:00:00 +0000 http://vk1od.net/balun/application/Z5.html http://vk1od.net/balun/application/Z5.html-06/05/11 Baluns Comment on QEX article - "Coaxial Traps for Multiband Antennas, the True Equivalent Circuit" Mon, 02 May 2011 00:00:00 +0000 http://vk1od.net/antenna/coaxtrap/QexKom.htm http://vk1od.net/antenna/coaxtrap/QexKom.htm-02/05/11 Antennas A review of the Aoyue 937+ Sun, 17 Apr 2011 00:00:00 +0000 http://vk1od.net/misc/937+/937+.htm http://vk1od.net/misc/937+/937+.htm-17/04/11 Other Electronic fluorescent light starters Fri, 15 Apr 2011 00:00:00 +0000 http://vk1od.net/misc/ElectronicFlouroStarter.htm http://vk1od.net/misc/ElectronicFlouroStarter.htm-15/04/11 Other Heater Delay Timer Tue, 12 Apr 2011 00:00:00 +0000 http://vk1od.net/module/hdt2/index.htm http://vk1od.net/module/hdt2/index.htm-12/04/11 Hardware DTR - PTT interface adapter Sun, 10 Apr 2011 00:00:00 +0000 http://vk1od.net/tx/DtrPtt/index.htm http://vk1od.net/tx/DtrPtt/index.htm-10/04/11 Transmitters RX1 Noise Bridge - VK1OD build Fri, 08 Apr 2011 00:00:00 +0000 http://vk1od.net/measurement/NoiseBridge/RX1.htm http://vk1od.net/measurement/NoiseBridge/RX1.htm-08/04/11 Measurement QRZ forums Mon, 04 Apr 2011 00:00:00 +0000 http://vk1od.net/misc/QrzForums.htm http://vk1od.net/misc/QrzForums.htm-04/04/11 ARRL Noise Bridge worked example reworked Sun, 03 Apr 2011 00:00:00 +0000 http://vk1od.net/measurement/NoiseBridge/ArrlNoiseBridge.htm http://vk1od.net/measurement/NoiseBridge/ArrlNoiseBridge.htm-03/04/11 Measurement Generic noise bridge calculator Sat, 02 Apr 2011 00:00:00 +0000 http://vk1od.net/calc/nbc2.htm http://vk1od.net/calc/nbc2.htm-02/04/11 Software RX1, RX2 Noise bridge calculator Sat, 02 Apr 2011 00:00:00 +0000 http://vk1od.net/calc/nbc1.htm http://vk1od.net/calc/nbc1.htm-02/04/11 Software Definition: Current Balun, Voltage Balun Sat, 19 Mar 2011 00:00:00 +0000 http://vk1od.net/balun/concept/VoltageCurrent.htm http://vk1od.net/balun/concept/VoltageCurrent.htm-19/03/11 Baluns Field Strength Calculator (FSC) update - V1.0.12 Wed, 02 Mar 2011 00:00:00 +0000 http://vk1od.net/software/fsc/support.htm http://vk1od.net/software/fsc/support.htm-02/03/11 Software Baluns in antenna systems Mon, 20 Dec 2010 00:00:00 +0000 http://vk1od.net/balun/concept/cm/index.htm http://vk1od.net/balun/concept/cm/index.htm-20/12/10 Baluns Yaesu FL2100Z Thu, 25 Nov 2010 00:00:00 +0000 http://vk1od.net/tx/FL2100Z/index.htm http://vk1od.net/tx/FL2100Z/index.htm-25/11/10 Transmitters Folded Half Wave Dipole Sun, 24 Oct 2010 00:00:00 +0000 http://vk1od.net/antenna/FoldedDipole/index.htm http://vk1od.net/antenna/FoldedDipole/index.htm-24/10/10 Antennas Half Folded Half Wave Dipole Wed, 20 Oct 2010 00:00:00 +0000 http://vk1od.net/antenna/HalfFoldedDipole/index.htm http://vk1od.net/antenna/HalfFoldedDipole/index.htm-20/10/10 Antennas Tapping an air cored RF inductor Tue, 19 Oct 2010 00:00:00 +0000 http://vk1od.net/tx/concept/TappedCoil/index.htm http://vk1od.net/tx/concept/TappedCoil/index.htm-19/10/10 Transmitters StationMaster on 40m Fri, 15 Oct 2010 00:00:00 +0000 http://vk1od.net/antenna/StationMaster/40.html http://vk1od.net/antenna/StationMaster/40.html-15/10/10 Antennas Exploration of a design for an 80m vertical antenna - Part I Thu, 14 Oct 2010 00:00:00 +0000 http://vk1od.net/antenna/80mVertical/index.htm http://vk1od.net/antenna/80mVertical/index.htm-14/10/10 Antennas Counterpoise - what does it mean? Sun, 10 Oct 2010 00:00:00 +0000 http://vk1od.net/antenna/misc/CounterPoise.htm http://vk1od.net/antenna/misc/CounterPoise.htm-10/10/10 Antennas A simple explanation of the so called current forcing property of a quarter wave transmission line Wed, 06 Oct 2010 00:00:00 +0000 http://vk1od.net/antenna/misc/CurrentForcingQW.htm http://vk1od.net/antenna/misc/CurrentForcingQW.htm-06/10/10 Antennas