Antennas, experiments, engineering and other articles of interest to radio folks.
SOLD I am selling this radio for a friend. He is the original owner and builder. It is a Heathkit SB-102 transceiver with HB-23-A external power supply with speaker. This includes the original two-pin microphone. This thing is old… very very old. It does power up as shown in the photographs below. I did attach … Read more
This final installment about the 6m LFA Yagi Antenna shows the technique to hold copper pipes to the boom using home center PVC plumbing materials.
Here is a step by step photo album showing how I prepared home center copper pipe for use in a three element Loop-Fed-Array Yagi-Uda antenna (aka LFA Yagi Antenna).
The Coplanar Loop Fed Array (LFA) Yagi-Uda design from G0KSC provides an excellent design foundation for an all copper version of a 3 element 6m balunless beam with superior front to back performance. Shown are comparisons between model simulations and prototype measurements.
The clever application of the folded dipole loop, computer science iteration techniques and NEC simulation to Yagi-Uda design results in a panoply of practical planar Loop Fed Array, LFA Yagi antenna recipes.
The traditional collinear J-Pole, aka Super-J, improves the basic J-Pole. Are further improvements possible? By replacing the phasing stub with a simple coil, the answer is yes. The result is the Collinear J-Pole.
Results from station 6 of the Appalachian Trail Golden Packet attempt from Stony Man mountain.
Even a 1B ARRL Field Day Station offers visitors a rare glimpse into Amateur Radio.
What’s the best format to send your geographic coordinates using Morse Code? Degrees, Degrees-Minutes, Degrees-Minutes-Seconds, Grid Squares? We take a look at the various formats and use a stopwatch to measure the send time.
Learn from our six successful years rolling out a computer network for the ARRL Field Day. Tips, techniques, dos and don’ts are among the highlights.
Basic tests of the LNR Precision EF-10/20/40 multi-band portable HF EFHW antenna including S11, SWR and a bandwidth check of the match box.
The background and details of the LNR (Par Electronics) EF-10/20/40 end fed half-wave multi-band portable HF antenna. Come see what’s inside the mysterious “black box.”
A reinforced Subaru through-hole NMO installation using silver epoxy and a metal plate stiffener accommodates the 62 inch Diamond SG7900A dual-band mobile antenna.
Fun times await participants in the 2012 Virginia QSO Party. This post links to Official Rules, Information and Past Statistics.
The Northern Virginia team of Ham Radio operators and companion hikers manned Hawksbill Mountain for the 2011 Appalachian Trail Golden Packet event. Gear included a Kenwood D710 with Green Light Lab GPS, 2m Collinear J-Pole and a 70cm collinear J-Pole.
Return Loss and SWR measurements of a permanent 2m whip installation mid-roof of a Ford Taurus. The effect of doors is shown.
Highlights from the installation of a 3/8 inch NMO permanent mount into a 1998 Ford Taurus rooftop.
To function as intended, the J-Pole antenna needs RF electrical isolation from its mount. Here’s why and in technicolor no less.
K3CDQ asks: I have an old computer with lots of 2002, 3 and 4 software on it. I have thirty years of ham contacts logged in a data base that I worked up using Microsoft Works 2004. I now have a new computer with all 2010 and 2011 software on it and running XP. I … Read more
Ground Rods… so easy a pre-teen can do it. Presented is a method learned from other hams on how to install a ground rod with minimal or no hammering. Using a watering can, even children can sink an 8 foot ground rod into the ground. All it takes is water and time.
My G3TXQ Hexbeam gets a new metal backbone to accommodate a VHF beam antenna. A byproduct is a much stronger antenna assembly than the common Hexbeam approach.
Real measured data reveal the UHF (PL259 and SO239) connectors have real limitations.
Lab tests show post WW2 connector designs perform exceptionally well up to 500 MHz. The SMA, BNC, TNC and N connectors are great.
We pit the PL-259 (and SO-239) against more recent connectors. This is the list of contenders plus a description of the test setup.