A Super J-Pole Antenna for the 70Mhz (4m) Amateur band.
The Vortex ‘Super J-Pole’ Antenna consists of a five eighth wave vertical radiator, a half wave tuning section and a half wave top section. At the base, a quarter wave matching stub forms the classic ‘J Shape’. The addition of the extra half wave top section boosts the gain over a standard J-Pole. The Super J-Pole has an added advantage that tuning can be varied over a fairly wide frequency range by moving the feed-point location up or down. This also gives the user finer control over the impedance and match. The antenna is end fed and has an omni-directional radiation pattern and requires no ground plane or radials. The antenna has a nice low angle of radiation, typically 8 degrees when mounted at 4m in height. This angle reduces further the higher the antenna is mounted. A typical installation with the antenna at 8 meters above ground sees the angle reduce to 5 degrees and the gain increases to 7.29dbi when ground reflections are added….
Read Full Article: Link
Antenna
Stealth Antennas by G0KYA
The first edition of Stealth Antennas quickly became the ‘must have’ antenna book for everyone who wasn’t living in acres of land. T... Read more
The Air Jupiter End Fed Co-Linear Antenna
⭐️launching today⭐️ The Air Jupiter End Fed Co-Linear Antenna! Here’s a video, 150watts, VSWR 1:3:1, Details to Follow 73’s Tom #HamRadio #SOTA #AvGee... Read more
Ham Radio experiment – End fed half wave antenna sloper vs flat horizontal orientation
https://youtu.be/BgEtQOS8mY0 Read more
New Antenna Physics Book from ARRL!
Written to bridge the gap between basic theory and graduate-level engineering texts, the second edition of Antenna Physics: An Introduction includes n... Read more
How to install a Horizontal Waller Flag antenna at 150 foot
The Horizontal Waller Flag antenna is a produced and sold by Carlos N4IS http://top-beam.com/ The boom on this one is 44 feet long. Interlaced... Read more
IOio Antenna
Scheme nº1: Scheme of the IOio antenna “FM ham satellites can efficiently be worked in two ways, one of them sitting in our armchair with a comp... Read more
Cushcraft R9 covers 6,10,12,15,17,20,30,40,80 Meters
This multiband vertical designs provide 9 band coverage encompassing the 6, 10, 12, 15, 17, 20, 30, 40 and 80 meter bands. Cushcraft achieved a majo... Read more
Another Difficult Antenna Situation
Tim, W4FTP, asks how he can use some tall but skinny trees along the back of his property as part of his antenna system. We take a look, and your comm... Read more
Warning: file_get_contents(https://plusone.google.com/_/+1/fastbutton?url=https%3A%2F%2Fqrznow.com%2Fa-super-j-pole-antenna-for-the-4m-70mhz%2F): failed to open stream: HTTP request failed! HTTP/1.0 404 Not Found in /home/qrznow/public_html/wp-content/themes/goodnews5/framework/functions/posts_share.php on line 151
){kind=link}