In order to ascertain the extent to which the dipole for 30/40-meter affected tribander I performed a number of measurements. These were conducted during October 2014, and were limited mainly to the 20-meter band. The results can be summarized as follows:
1. With the dipole along the radiator and the dipole coax shorted in the lower end
* -3 dB relative to a reference station.
* -2 dB relative to a reference dipole.
2. With the dipole along the radiator and the feeder terminated with a capacitor for SWR = 1 on the tribander.
* The -3 dB compared with reference dipole. (1 dB worse than with shorted coax).
* In direct comparison with shorted coax the signal is 3 dB less with variable capacitor. (Does not agree with the measurement to reference dipole).
3. Failed to change the F / B ratio by shifting between the capacitor and short circuiting.
4. With the dipole along with the radiator and dipolkoaxen closed with dummy load of 50 ohms and 13% dumped effect (of what is fed to the FB 53an).
* Difference = 0 dB compared to referensdipol (compensated).
5. With the dipole along the boom.
* +2 dB relative to the reference station
* +3 dB relative to the reference dipole.
That is: The Gain of the tribander is measured to 3 dBd.