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Estimated Field Strength from Amateur Radio Stations -- ARRL #1
The external area around ARRL HQ is known to have a fairly high ambient noise level, primarily from power-line related noises. Measurements were made in the ... Learn More
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Ferrite choke kits for coax, USB, and ethernet - KF7P.com
Time to reduce the annoying RF sources that are picked up in your radio, or cause havoc with interconnecting shack equipment. Our choke kits provide the ... Learn More
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Bill Becomes a Law
"RFI Bill" Becomes Law; Amateur Radio Benefits! RFI Regulatory Information By W. Dale Clift, WA3NLO Deputy Manager, Membership Services, ARRL From November 1982 ... Learn More
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LF (Low Frequency) - ARRL
The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources. Learn More
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Electric Fence Noise - ARRL
Let's now take a closer look at the problem of unwanted radio noise from an electric fence, and ways to find and fix it. Virtually all radio interference ... Learn More
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ARRL Letter Issue
Apr 8, 2021 ... Radio frequency interference (RFI) has been a problem for ham radio operators and SWLs (shortwave listeners) since the radio hobby began. Noise ... Learn More
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2012-2016 Extra Class Question Pool - ARRL
noise sources; DSP noise reduction; noise blankers. SUBELEMENT E5 ... As a high-pass filter used to block RFI at the input to receivers. B. As a low-pass ... Learn More
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ARRL Letter
Apr 8, 2021 ... Radio frequency interference (RFI) has been a problem for ham radio operators and SWLs (shortwave listeners) since the radio hobby began. Noise ... Learn More
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FCC Special Counsel Laura Smith Visits ARRL
Spending all Thursday afternoon with ARRL Lab staff, Smith discussed power line noise and how it can affect Amateur Radio. "Since Riley had retired last year, ... Learn More
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ARRL Handbook Reference 2011-2023 Editions
The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources. Learn More
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