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Re: Topband: HEBA antenna

To: topband@contesting.com
Subject: Re: Topband: HEBA antenna
From: Jeff Blaine <KeepWalking188@ac0c.com>
Date: Sun, 21 Apr 2024 11:00:03 -0500
List-post: <mailto:topband@contesting.com>
What I found interesting in the HEBA103 document was that it seemed the FS measurements were taken at ground level along two compass points.  If I'm not mistaken, the power radiated is spread out over a 3-dimensional space and from that standpoint, I don't see how improved FS measurements taken on the near field at ground translate directly into "high efficiency."

But on this topic, the only think I know **for certain** is that I'm a mental micro-midget compared to Maxwell.

73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com

On 4/20/2024 3:19 PM, Jim Brown wrote:
On 4/20/2024 9:18 AM, Joe Subich, W4TV wrote:
Similarly, to the AM broadcaster, "Broadband" simply means sufficient
bandwidth to keep the transmitter happy and avoid distortion of an
IBOC digital signal.  That is far more narrow than even a "50 KHz
under 1.5:1" for amateurs on 160.

Great points, Joe. I grew up a mile or two from a 5kW DA-N on 930 kHz, and as a college student worked at the station. One summer, I helped the chief engineer silver-solder new radials to new ground screens for the 4-tower array. The bandwidth issue jumped out at me as I drove through one of their nulls -- where the carrier cancelled, the sidebands didn't.

73, Jim K9YC

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