Antenna radiator decoupling stub flub?
Measurements and analysis suggest why quarter-wave stubs fail to completely isolate radiator conductors on multi-band antennas. Possible improvements are shown.
Where quarter-wave radiator decoupling stubs work… and don’t work
A 1950 patent combined with modern simulation offer hope, but caution of using transmission line decoupling stubs in antenna radiators.
Winlink and Modems: When to not cross the streams
Those opposed to Winlink are attempting to hold removal of the 300 baud HF data limitation hostage.
When an N connector isn’t
You would think the world of RF connectors of the pedigree of the “N” would rigorously follow the dictates of the standards that define them. Thankfully most do, but exceptions arise and here is one such example of why it pays to “trust, but verify.”
J-pole: Where a choke is no joke
Measurements reveal the effects of common mode current on the J antenna.
HT Antenna Comparisons
Does one really need to upgrade the antenna that came with your HT? Presented are EIRP measurements of various aftermarket HT aerials to help understand the trade space.
Fair-Rite 2661480002 Type 61 Ferrite Slide-on Chokes
A closer look at type 61 ferrite material in various configurations for RG58 reveals the benefits and insufficiencies of chokes in series.
Finding facts of Fair-Rite Ferrites
Learning more about several ferrite compositions from the Fair-Rite manufacturer including where to buy them.
Where a choke chokes
I measure one example of a ferrite coax choke for response over frequency to understand its suitability for VHF and UHF.
EFHW HT antenna functions without additional counterpoise
EIRP measurements of the 2m end-fed half-wave HT antenna from MFJ aids understanding a dipole is a dipole no matter where you feed it.
WWVB DX Virgin No More
Thanks to a spiffy new Airspy HF+ SDR receiver I can scratch listening to WWVB off the bucket list.
MFJ-259 Battery Holder Repair
My MFJ-259 HF/VHF SWR Analyzer required yet another repair to its internal battery holders.
NIST takes aim at WWVB, WWV and WWVH
The National Institute of Standards and Technology appears to have the time and frequency broadcast stations on the chopping block given the info contained in their 2019 budget proposal. This is what I wrote to my senator and congressman.
DX Engineering supports AHVD antenna
DX Engineering supports the build of the Asymmetrical Hatted Vertical Dipole (AHVD) antenna with standard and two custom parts.
When antenna tilt matters
We test a popular VHF/UHF dual band antenna at various angles to reveal antenna tilt on a vehicle matters only in certain circumstances.
The self-absorbed ham
A writer details how his ham father dissed his family by losing himself in technology. The story serves as a canary in the coal mine for “social media” then and now.
NVIS works very well… except when it doesn’t
Near Vertical Incident Skywave (NVIS) propagation works wonders when the bands cooperate, but can slam the door shut at any moment.
Diamond NR770HBNMO vs. Comet M-24M
The Diamond Antenna NR770HBNMO paired with their K515S insulated luggage rack mount provides measurable and observable upgrade for my 2015 Subaru Forester 2m/440 mobile.
Radials mitigate feedline and mast currents, tests reveal
Antenna patterns from a Diamond X50NA reveal how radials of proper size mitigate current running down the feedline and mounting structure.
Hurricane Maria, Puerto Rico and how hams helped
Compare and contrast conflicting accounts of the amateur radio response to Hurricane Maria featuring what worked well, what didn’t and why resourceful hams combat nature and management.
J antenna and variations thereof
There are many ways to morph the basic J antenna into useful forms.
Sunspots and HF propagation
QSO data from a state QSO party reveal trends in HF usage correlating with sunspot numbers.
Virginia Packet Fund Raiser
The organizers of the Virginia Packet Network are asking for a few bucks to expand service outside of Virginia.
J Antenna Design Patent Grant
USD798847S1 showcases one more incremental step towards a J antenna that works with masts and feedlines.