07-01-2016, 03:16 PM
Hi Rob.
I just found a little more information regarding the noise characteristics of this antenna design. Below is a snippet from the linked-to article:
"Additionally, the unun will eliminate (virtually) all "common mode" currents on the feedline. This is important for eliminating the pickup of local electrical noise from homes and power distribution lines. The coax, being connected to ground through a DC path will eliminate all but the differential currents ... pretty cool, huh? Finally, since the antenna is connected directly to Earth ground through the secondary of the transformer, static buildup cannot occur - the antenna is a dead (DC) short to ground. This is important to sensitive, solid state radios. The 9:1 transformer provides: 1. a much flatter broadband impedance response, 2. a static elctricity-free antenna system (no buildup), 3. common mode noise immunity (if space wound as shown)."
Here's the full article: www.mobileers.com/main/wp-content/uploads/2013/01/9-to-1-Balun-for-End-Fed-Antenna.pdf
I just found a little more information regarding the noise characteristics of this antenna design. Below is a snippet from the linked-to article:
"Additionally, the unun will eliminate (virtually) all "common mode" currents on the feedline. This is important for eliminating the pickup of local electrical noise from homes and power distribution lines. The coax, being connected to ground through a DC path will eliminate all but the differential currents ... pretty cool, huh? Finally, since the antenna is connected directly to Earth ground through the secondary of the transformer, static buildup cannot occur - the antenna is a dead (DC) short to ground. This is important to sensitive, solid state radios. The 9:1 transformer provides: 1. a much flatter broadband impedance response, 2. a static elctricity-free antenna system (no buildup), 3. common mode noise immunity (if space wound as shown)."
Here's the full article: www.mobileers.com/main/wp-content/uploads/2013/01/9-to-1-Balun-for-End-Fed-Antenna.pdf