Sharp; Regular; Wide; Fixed - Acom 04AT Operating Manual

number, i.e. each output can be declared for each type, regardless of the other ones.
Unless the operator changes it, REGULAR (normal) type is set by default for all four
antenna outputs.

4.1.1 SHARP

For moderately reduced dimensions, such as 20-25m vertical for operation at 160m,
you may select SHARP (narrow or small-band, with sharp tuning). The width of the fre-
quency segments will be approximately 0.25% of the operating frequency (e.g. 5kHz
at 160m).
This option is convenient for small-size and low-band antennas that are artificially
lengthened (moderately) with load coils, or "hats / caps", or antennas with preliminary
matching, with dipoles, verticals or loops that are not too short, with selective circuits
(traps or stubs) included in the design, etc.

4.1.2 REGULAR

Full-size dipoles, inverted V, loops, 2-3 element square or delta loops, Yagi, etc. com-
mon antennas, should be declared as type REGULAR (normal) – the option is provid-
ed as basic by default. The width of the frequency segments is approximately 1% of
the operating frequency.

4.1.3 WIDE

Naturally broad-band antennas could be declared as WIDE (broad-band). The width of
the frequency segments is approximately 4% of the operating frequency. This option
is convenient for special broad-band radiators, e.g. exponential, log-periodic, "thick" or
aperiodic (with absorbing loads) – rhombic etc. similar antennas.

4.1.4 FIXED

An extreme reduction of the physical dimensions of antennas, such as for a loop of
2-3m diameter for 80m band, would probably limit the capability to operate on a single
fixed frequency only. If this is the case, select FIXED (for fixed frequencies) type. Nat-
urally, you can also make the same choice with more broad-band antennas, if this is
convenient for any other reason. This option is also convenient for reducing the proba-
bility of operating with random settings at specifically set frequencies.

4.2 TUNER ASSIGNMENT AND UNASSIGNMENT

Tuner assignment and unassignment is done in the USER PREFERENCES menu of
the amplifier.
If the top row of the "Antenna tuner/switch installed NO – YES" menu is not selected (if
it is shaded), first select it with the
To assign the tuner, use the SELECT button and select YES. To unassign the tuner,
use the SELECT button and select NO. Leave the menu with the EXIT button.
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ITEM or ITEM buttons.