Pennant/Flag antennas.

• Use insulators where the transformer and termination resistor connect, to take mechanical strain away from components.
• Reception direction. If you are standing under the termination resistor, reception is from the direction of the transformer.
• One of the problems with poor reception, and poor front to back is coupling to the transmit antenna. Transmit element detuning is necessary. A relay may have to be installed at the transmit antenna feed point to disconect the coax, or to disable other element tuning components while receiving.
• Pennant and flag antennas, in order to receive low angles, need to be decoupled from ground to achieve ground independence.
• Ground independence requires a decoupling of common mode of the coax line shield. Decoupling is done by physically separating the primary and secondary of the matching transformer, to minimize capacity between the two windings. If the matching transformer is mounted in a metal box, it can only increase coupling between the windings. Signal loss may not be noticeable on higher angle signals as loss starts with the lowest angles.
• This loss of signal due to ground dependence is due to an effect called the Pseudo- Brewster angle and explained in the ARRL Antenna Handbook.
• Increased decoupling of the coax cable is often done by adding turns to a ferrite core after the transformer where the coax first meets the ground.
• A deep null on the back of the antenna is useful for interference control.
• Typical terminations are 905-915 ohms point terminated Pennant, and 940-950 ohms Flag.
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73
Bruce-K1FZ