Reg,

I am planning on building an antenna based on midload.exe. For some reason the
'notes' do not appear so I cannot read them.

I plan to feed the antenna with coax. What are the hookup instructions? Is the
coil actually cut? What does link coupling refer to?

There is a similar antenna in the ARRL handbook, however it does not appear to
be cut. The shield is connected to a center tap and the coax center is tapped a
few turns out.

The program predicts 40 turns with a coil tap of .8 turns. Which connection is
this?

Thanks - Dan

Dan,

To read the notes again, it is necessary to "go back to the start of
program" from the 'results' screen.

The loading coil is always continuous from one end to the other. There
are no breaks or cuts in it.

The coax line can have its braid attached directly to the centre of
the coil with the inner coaxial conductor tapped into the coil a few
turns away from the centre. But this is not recommended.

It is much easier to construct and adjust the number of link-turns by
using a link-coupling coil. The link-coupling coil is wound over the
top of the center of the main coil and is well insulated from it. You
can use the same type of wire for both main and coupling coils.

Close-wound enamelled magnet wire is suitable except at the higher
frequencies where not many turns are needed.

With link coupling either coax or balanced-twin feedline can be used.
It is easier to change the number of turns on a link coil.

It may be necessary to change the number of turns on the link coil to
provide an impedance match with the feedline impedance. The computed
number of turns on the link coil is approximate. Only a whole number
of turns is possible in practice.

When the feedline is directly tapped into the main coil, a soldering
iron and other work is needed to change the number of tap turns.

Don't forget the antenna is a one-frequency, one-band, very narrow
bandwidth antenna. To resonate the antenna exactly to a particular
frequency it is necesary to prune the length of the loading wires or
loading rods at each end of the main coil.

The antenna is easier to construct and adjust for use in a confined
space such as an attic, at frequencies between 1.8 and 10 MHz.

Good DX in 2006.
----
Reg, G4FGQ.

============================================

I am planning on building an antenna based on midload.exe. For some
reason the
'notes' do not appear so I cannot read them.

I plan to feed the antenna with coax. What are the hookup
instructions? Is the
coil actually cut? What does link coupling refer to?

There is a similar antenna in the ARRL handbook, however it does not
appear to
be cut. The shield is connected to a center tap and the coax center
is tapped a
few turns out.

The program predicts 40 turns with a coil tap of .8 turns. Which
connection is
this?

Thanks - Dan

Reg,

I am running Linux and using dosemu to run the programs. It is probably an issue
with the dosemu.

The link-coupling coil is essentially a balun?

I am building a 40 foot 80 meter dipole (limited space). The program predicts
about 10 Ohms input impedance and 1.1 'link coupling' turns. Does that imply
essentially wrapping one turn on the coil for the coax connection? Can one turn
provide enough impedance to match to the coil?

Thanks again - Dan

Reg Edwards wrote:
Dan,

To read the notes again, it is necessary to "go back to the start of
program" from the 'results' screen.

The loading coil is always continuous from one end to the other. There
are no breaks or cuts in it.

The coax line can have its braid attached directly to the centre of
the coil with the inner coaxial conductor tapped into the coil a few
turns away from the centre. But this is not recommended.

It is much easier to construct and adjust the number of link-turns by
using a link-coupling coil. The link-coupling coil is wound over the
top of the center of the main coil and is well insulated from it. You
can use the same type of wire for both main and coupling coils.

Close-wound enamelled magnet wire is suitable except at the higher
frequencies where not many turns are needed.

With link coupling either coax or balanced-twin feedline can be used.
It is easier to change the number of turns on a link coil.

It may be necessary to change the number of turns on the link coil to
provide an impedance match with the feedline impedance. The computed
number of turns on the link coil is approximate. Only a whole number
of turns is possible in practice.

When the feedline is directly tapped into the main coil, a soldering
iron and other work is needed to change the number of tap turns.

Don't forget the antenna is a one-frequency, one-band, very narrow
bandwidth antenna. To resonate the antenna exactly to a particular
frequency it is necesary to prune the length of the loading wires or
loading rods at each end of the main coil.

The antenna is easier to construct and adjust for use in a confined
space such as an attic, at frequencies between 1.8 and 10 MHz.

Good DX in 2006.
----
Reg, G4FGQ.

============================================

I am planning on building an antenna based on midload.exe. For some
reason the

'notes' do not appear so I cannot read them.

I plan to feed the antenna with coax. What are the hookup

instructions? Is the

coil actually cut? What does link coupling refer to?

There is a similar antenna in the ARRL handbook, however it does not

appear to

be cut. The shield is connected to a center tap and the coax center

is tapped a

few turns out.

The program predicts 40 turns with a coil tap of .8 turns. Which

connection is

this?

Thanks - Dan