Blog
The J-Pole Antenna Unmasked
At the June Zoom meeting of the Chelsea Amateur Radio Club , Wesley Cardone (N8QM) will give a simplified presentation of the J-Pole antenna. Club meetings occur on the 2nd Tuesday of each month. The premise of this presentation is to explain in simplified and down-to-earth fashion the electromagnetics of antennas while “tuning” the presentation…
What is characteristic impedance, anyhow?
What distinguishes “impedance” from “characteristic” impedance? A 1 foot length of RG-8X coax has a characteristic impedance of 50 Ohms. But does that cable present a 50 Ohm resistance to DC current flow? Can you describe the current flow that exists on such a coax cable if the end is open? When you understand characteristic…
Preparedness
Being PreparedBy Tim Bair, WD8PMDEmergency Coordinator, Jackson County MichiganJan, 2022 Prepare they say ….. This begs the question, have you? As amateur radio operators, some of us tend to think along the lines of preparedness and public service in whatever form that may take. Here in Michigan, we are very lucky in that most natural…
NVIS Antenna for ARES/RACES
NVIS Antenna / ECOMM CommunicationsECOMM Notes: Tim, WD8PMD, Oct-2021 Why choose an NVIS antenna system? In the world of ECOMM we need a method that offers a quick solution to our regional communication needs. I’m speaking of communications that cover the range of a few miles to a few hundred miles. While UHF / VHF…
How Do You Calibrate Your HF Rig’s S-meter?
Few people realize this but S-meters on most transceivers are not calibrated to reflect accurate readings. But did you know that most rig’s S-meters are easily adjusted for an accurate calibration. But even if you for whatever reason don’t wish to monkey around with your rig, you can at least find out what your S-meter…
What is Input Impedance, Anyhow
As amateur radio operators we typically look at any input impedance specification and think 50 Ohms. But what is 50 Ohms? Buried within the whole topic of input impedance is a “characteristic impedance.” At this point we typically lose amateurs thinking we are moving into rocket science. But this stuff is really simple as you…
Special Event Station W8J at the Jackson County Fair
At the Jackson County Fair of 2021 at about 5 PM, the Cascades Amateur Radio Society had a booth and was displaying amateur excellence to the public at large. In the first photo you can see both Dave (W3IGT) and Bill (KD8AAD) in the near field actively working the special event station that the club…
Transmission Line Analytics Applied to a Mag Mount Antenna
Amateur radio operators often forget that a feedline or transmission line has an effect on the vector impedance of the antenna it serves. If the antenna is resonant (50 + j0 Ohms) for the input frequency, then any length of coax is irrelevant. But if the antenna vector impedance is something else (which it ALWAYS…
Mag Mount Antenna Optimization & Feedline Analytics
The mag mount antenna may possibly be categorized as a commodity in both amateur radio and all hobbyist communications. Its installation is pretty much plug-and-chug except for a slight positioning of the transmitting element by means of a set screw. The user of the mag mount antenna typically uses an SWR meter to position the…