Using data from Tab. 1 3, I made diagrams for three transformer's
loads 300, 450 and 600 Ohms. The diagrams show:

An input resistance
vs. frequency (Fig. 2),

A VSWR relative
to 50 Ohms vs. frequency (Fig. 3),

A VSWR relative
to 75 Ohms vs. frequency (Fig. 4),

The efficiency
vs. frequency (Fig. 5).
As it was mentioned above,
the efficiency is the most important parameter of any RF transformer.
The RF autotransformer has a high efficiency (87 percent) only
on a range of 160 meters while this one is loaded to

600
Ohms. The efficiency falls sharply on other amateur HF ranges.
As for a range of 40 meters the RF autotransformer
has the efficiency of 6535 percent (it depends on the transformer’s
load). As for a range of 30 meters the RF autotransformer has
the efficiency of 52 and 45 percent while this one is accordingly
loaded to 600 and 450 Ohms. The efficiency is more in comparison
with RF transformers shown in Fig. 3
and 7,
Part I. Alas, while the autotransformer has a high
efficiency, it has a low input resistance
and accordingly, a high VSWR! Therefore it is impossible to use
a 50 or 75Ohm coaxial cable together with the autotransformer.
