Question 1

What about RFI, Bitey-Microphone and other problems usually associated with a common end fed antennas?

Danny-E73M · Accepted Answer

Unlike a commonly used End-fed antennas with 9:1 UNUNs and non-resonant length of wire, EFHW antennas are not prone to high common mode current and problems associated with it mainly due to the high common mode isolation of the transformer (MyAntennas designs) and use of the resonant length of wire placing the current minima at the feed point. RF interference in the home is common with any antenna without proper Current BALUN, like Dipoles, OCF dipole antennas, G5RV, ZS6BKW etc. or when the antenna is very close or installed above radio room like in the attic or routed over the home. Avoid the routing of coaxial cable under or parallel to the radiating wire, in that case, antenna radiator will couple the energy to the coaxial shield of the feedline and cause common mode current on it which will be routed towards your station and manifested as RFI, Bitey mic. noise in speakers etc. Just like any center fed dipole without proper BALUN and coaxial cable swayed on one side, common mode current on a shield of the cable is unavoidable.

Question 2

What about RFI, Bitey-Microphone and other problems usually associated with a common end fed antennas?

Danny-E73M · Accepted Answer

Unlike a commonly used End-fed antennas with 9:1 UNUNs and non-resonant length of wire, EFHW antennas are not prone to high common mode current and problems associated with it mainly due to the high common mode isolation of the transformer (MyAntennas designs) and use of the resonant length of wire placing the current minima at the feed point. RF interference in the home is common with any antenna without proper Current BALUN, like Dipoles, OCF dipole antennas, G5RV, ZS6BKW etc. or when the antenna is very close or installed above radio room like in the attic or routed over the home. Avoid the routing of coaxial cable under or parallel to the radiating wire, in that case, antenna radiator will couple the energy to the coaxial shield of the feedline and cause common mode current on it which will be routed towards your station and manifested as RFI, Bitey mic. noise in speakers etc. Just like any center fed dipole without proper BALUN and coaxial cable swayed on one side, common mode current on a shield of the cable is unavoidable.

Question 3

What about RFI, Bitey-Microphone and other problems usually associated with a common end fed antennas?

Danny-E73M · Accepted Answer

Unlike a commonly used End-fed antennas with 9:1 UNUNs and non-resonant length of wire, EFHW antennas are not prone to high common mode current and problems associated with it mainly due to the high common mode isolation of the transformer (MyAntennas designs) and use of the resonant length of wire placing the current minima at the feed point. RF interference in the home is common with any antenna without proper Current BALUN, like Dipoles, OCF dipole antennas, G5RV, ZS6BKW etc. or when the antenna is very close or installed above radio room like in the attic or routed over the home. Avoid the routing of coaxial cable under or parallel to the radiating wire, in that case, antenna radiator will couple the energy to the coaxial shield of the feedline and cause common mode current on it which will be routed towards your station and manifested as RFI, Bitey mic. noise in speakers etc. Just like any center fed dipole without proper BALUN and coaxial cable swayed on one side, common mode current on a shield of the cable is unavoidable.

Question 4

What about RFI, Bitey-Microphone and other problems usually associated with a common end fed antennas?

Danny-E73M · Accepted Answer

Unlike a commonly used End-fed antennas with 9:1 UNUNs and non-resonant length of wire, EFHW antennas are not prone to high common mode current and problems associated with it mainly due to the high common mode isolation of the transformer (MyAntennas designs) and use of the resonant length of wire placing the current minima at the feed point. RF interference in the home is common with any antenna without proper Current BALUN, like Dipoles, OCF dipole antennas, G5RV, ZS6BKW etc. or when the antenna is very close or installed above radio room like in the attic or routed over the home. Avoid the routing of coaxial cable under or parallel to the radiating wire, in that case, antenna radiator will couple the energy to the coaxial shield of the feedline and cause common mode current on it which will be routed towards your station and manifested as RFI, Bitey mic. noise in speakers etc. Just like any center fed dipole without proper BALUN and coaxial cable swayed on one side, common mode current on a shield of the cable is unavoidable.

Question 5

What about RFI, Bitey-Microphone and other problems usually associated with a common end fed antennas?

Danny-E73M · Accepted Answer

Unlike a commonly used End-fed antennas with 9:1 UNUNs and non-resonant length of wire, EFHW antennas are not prone to high common mode current and problems associated with it mainly due to the high common mode isolation of the transformer (MyAntennas designs) and use of the resonant length of wire placing the current minima at the feed point. RF interference in the home is common with any antenna without proper Current BALUN, like Dipoles, OCF dipole antennas, G5RV, ZS6BKW etc. or when the antenna is very close or installed above radio room like in the attic or routed over the home. Avoid the routing of coaxial cable under or parallel to the radiating wire, in that case, antenna radiator will couple the energy to the coaxial shield of the feedline and cause common mode current on it which will be routed towards your station and manifested as RFI, Bitey mic. noise in speakers etc. Just like any center fed dipole without proper BALUN and coaxial cable swayed on one side, common mode current on a shield of the cable is unavoidable.

Question 6

What about RFI, Bitey-Microphone and other problems usually associated with a common end fed antennas?

Danny-E73M · Accepted Answer

Unlike a commonly used End-fed antennas with 9:1 UNUNs and non-resonant length of wire, EFHW antennas are not prone to high common mode current and problems associated with it mainly due to the high common mode isolation of the transformer (MyAntennas designs) and use of the resonant length of wire placing the current minima at the feed point. RF interference in the home is common with any antenna without proper Current BALUN, like Dipoles, OCF dipole antennas, G5RV, ZS6BKW etc. or when the antenna is very close or installed above radio room like in the attic or routed over the home. Avoid the routing of coaxial cable under or parallel to the radiating wire, in that case, antenna radiator will couple the energy to the coaxial shield of the feedline and cause common mode current on it which will be routed towards your station and manifested as RFI, Bitey mic. noise in speakers etc. Just like any center fed dipole without proper BALUN and coaxial cable swayed on one side, common mode current on a shield of the cable is unavoidable.