The May/June issue of QEX, ARRL’s bimonthly magazine for experimenters, is off the press and in the mail!
In this issue . . .
Michael Knitter, DG5MK, describes a complex-impedance analyzer that uses a heterodyning technique and high resolution ADCs to get good accuracy at low cost.
Robert H. Sternowski, WBØLBI, uncovers old measurements, which show that vertically and horizontally polarized noise can differ by tens of decibels in the lower HF bands.
Paulo Renato F. Ferreira, PY3PR, updates the Octopus V/I curve tracer by providing selectable scanning voltages for testing.
Maynard A. Wright, W6PAP, provides Octave software for computing the performance of transmission lines having a complex characteristic impedance.
Riccardo Gionetti, IØFDH, describes an automatic tracking filter for a DDS generator.
Euclides Lourenço Chuma, PY2EAJ, describes a modern RF power meter with accuracy that rivals the best commercial RF power meters.
Not a QEX subscriber? Sign up today at https://www.arrl.org/qex-subscription-form. You can also read a free sample article from this issue at http://www.arrl.org/this-month-in-qex.
Antenna
MFJ -225 HF/VHF, 1.8-170 MHZ GRAPHIC ANALYZER
MFJ-225 HF/VHF Two-Port Graphic Antenna AnalyzerTake RF testing to the next level with the new MFJ-225! All the basic analyzerfunctions you`ve... Read more
Acom HF antenna V101
Acom HF antenna V101 FEATURES The V101 – 03AT antenna system consists of the Broadband Inverted Vee Dipole Antenna V101 and the automatic... Read more
The AMSAT SA 2 m / 70 cm dual-band Yagi antenna is now available
The antenna has a 50-ohm designed driver. The Yagi has a unique element called a ‘Open Sleeve’ which is a director very close to the driven element... Read more
App - Mobile
New! RemoteHamRadio App
Hold a mega-station in the palm of your hand. Wherever you are, you can work DX and log it. Operate from our 18 unique stations to snag a new country,... Read more
CommCat 4 for Radio Control and Logging!
CommCat 4 is a radio control and logging program for radio amateurs who share a passion for talking to other hams around the world. CommCat works with... Read more
New ARRL Repeater Directory Will Leverage Crowdsourcing Technology
ARRL partner RFinder, the creator of a web and app-based directory of Amateur Radio repeaters worldwide, will supply all data for the 2017-2018 ARRL R... Read more
EchoLink for iOS version 2.10.18 is now available
EchoLink for iOS version 2.10.18 is now available in the App Store. This is a 64-bit build that is fully compatible with iOS 10 and modern iOS devices... Read more
iSDR for Iphone and Ipad
iSDR is a software defined radio application compatible with the iPhone®, iPod touch® and iPad™. iSDR is designed for experimenters, shortwave... Read more
Digital Modes
FT8Call 0.5 Released – New features, a MacOS build, APRS.fi spotting, and more!
“Howdy Folks, I’m excited to bring you the next development version of FT8Call, version 0.5, and boy do I have some fun stuff included i... Read more
Quicker-Turnaround Digital Modes in Experimental Stage for WSJT-X Suite
Recent sporadic-E propagation openings on 6 meters and elsewhere have pointed up the need for a digital mode having faster turnaround time than curren... Read more
Caution Urged in Using High Duty Cycle Digital Modes via Satellite
A report in ANS-288 discussed an experiment operating with the WSJT-X FT8 digital mode via satellite. Satellite operators have gained more experience... Read more
Digital Activity Days RDRC “01-10” – Rules
RDRC Objective: Attraction of radio amateurs to the development of digital reports and software for various digital modes. Participants: Licens... Read more
LoTW Now Accepting FT4 Contact
The latest TQSL update (Config.xml version 11.8), released on May 22, includes FT4 as a submode of MFSK. It also adds AISAT-1 and PO-101 in the satell... Read more
Review
Setting up a new RFinder M1DU
◇ Main Features LTE 4G, Android IP67 rugged smartphone, professional walkie talkie. ◇ Basic Info ◇ Release 2017 April ◇ Walkie talkie output 4W DMR; 4... Read more
Retevis RT82 Dual Band DMR Digital Two Way Radio at ML&S Overview
Retevis RT82 Description RT82 is a dual band DMR radio Frequency band:136-174 & 400-480MHz 10000 Contacts IP67 Waterproof Use T... Read more
FLEX-6400M from the ARRL Review
FLEX-6400M Radio Server SDR Features 100W PEP HF-6m operation All modes/all bands Integrated Remote Operation with Maestro, PC/ Laptop, iPad® or iPho... Read more
The Difference Between Yaesu WiresX And Hotspots
“In the world of Yaesu System Fusion and C4FM there seems to be a lot of confusion over access to the WiresX system from a hotspot. This time, I... Read more
Yaesu FT 891 Install And First Contact
“If you are thinking of adding a new radio to your shack or mobile check out this video on the new Yaesu FT-891! It is my opinion that you can... Read more