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Ham Radio . Magnum Experimentum

Antennas, experiments, engineering and other articles of interest to radio folks.

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  • Home
  • Radio Shorthand
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    • Morse Code
    • Phonetic Alphabet
    • Q Signals
    • RST Signal Report
  • Tech Talk
    • Antenna Gain
    • Antenna Counterpoise
    • Digital
    • Logging Software
  • Amateur Radio, Why?
  • About
    • Privacy Policy
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    • Request Account
    • Contact
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    • Advertise
  • Subjects
    • Activities
    • Antennas
    • contesting
    • Connectors
    • Digital Modes
    • EmComm
    • Installations
    • interfaces
    • Introspection
    • Lab Shootouts
    • Miscellaneous
    • mobile
    • NEC Shootouts
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    • power supply
    • Accessories
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S21

Effect of shields on ferrites

January 1, 2021April 14, 2019

A simple S21 test reveals conductive shields do not change the behavior or ability of a ferrite to perform the role of common-mode rf current choke.

Categories Antennas Tags banana plug, Fair-Rite, ferrite, measurement, RG-58, S21, type 61

Where a choke chokes

January 1, 2021September 20, 2018
N9TAX Slim Jim Antenna choke under test.

I measure one example of a ferrite coax choke for response over frequency to understand its suitability for VHF and UHF.

Categories Antennas Tags choke, common mode, ferrite, J-Pole, measurement, N9TAX, S21, UHF, VHF

Aluminum RF power splitters under test

January 1, 2021March 11, 2016
Two RF power splitters

Two examples of square aluminum RF power splitters built from 1973 plans reveal a 15 MHz difference from the claimed design frequency.

Categories Accessories Tags Aluminum, brass, coaxial, measurement, power splitter, S11, S21, splitter

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