开云体育

Yes, the NANOVNAs are capable of making these measurements. HOWEVER, and
that's a huge "however", the chassis of the NANOVNA needs to supply the
other portion of the wire. An end fed is only half the antenna. The other
half must be supplied by a long set of wires with a good connection to
earth (far more than a single earth rod) This is to provide a good
conductor against which the end fed whatever can work against.

Example: Ask yourself which of the following will radiate and why / why
not:


[image: image.png]
The top illustration is like connecting only one lead to a battery (if this
were DC). No current can flow as there is no return. Therefore, the top
will not radiate as there is no counterpoise, or, in more "accepted"
language among the amateur community, "ground".

The bottom will, indeed, radiate (a simple 1/2-wavelength dipole) as there
is a return for the current. This is analogous to connecting both
terminals of a battery (if this were DC).

Ideally the return for the chassis of the NANOVNA should be lossy to
prevent it from entering the measured resonant behavior of the EFW (end fed
wire).

Dave - W?LEV

--
Dave - W?LEV