Simplex Direct Tuning - Honeywell KHF 1050 Pilot's Manual

Frequency Band (MHz)
2.8
4.4
5.5
6.5
8.8
10.0
11.1
13.3
17.9
21.9
The transition between daytime and nighttime distances may occur gradually
over a several hour period. During this transition, communication distances
between the daytime and nighttime distances listed will generally be realized.
* At times,communication may not be possible on this band during this time-
frame. However, during periods of good propagation, worldwide communica-
tions may be realized.
Table 1 - Typical HF Signal Propagation Distance for Common
There are two types of frequency operation. "Simplex" is tuning the
same frequency for receive and transmit. "Semi-duplex" (sometimes
called "split") is tuning two different frequencies, one for receive and one
for transmit. It is important to know the requirements of the desired
ground station when tuning these frequencies. Virtually all aviation ser-
vices operate on simplex.

SIMPLEX DIRECT TUNING

1. Turn the left outer knob to FREQ. See
Figure 5. The frequency shown in the
upper row of the display is the receive fre-
quency indicated by the RX on right of the
display.
2. Select the desired frequency using the
right inner and outer concentric knobs.
The outer knob changes the frequency in
.1 MHz increments. The inner knob
changes the frequency in .001 MHz (1
KHz) increments or .0001 MHz (100 Hz)
increments, depending on the configura-
tion selected when the system was
installed.
Revision 0 Mar/2003
Daytime Distance (Miles) Nighttime Distance (Miles)
Up to 100; Often unusable Up to 400
Up to 200
Up to 300
100 to 600
200 to 800
300 to 1000
400 to 1200
600 to 1500 or greater
700 to 1800 or greater*
900 to 1800 or greater*
Aviation Bands
5
Up to 1000
100 to 1200
200 to 1500
400 to 1500 or greater
500 to 1800 or greater*
600 to 1800 or greater*
Often unusable
Often unusable
Often unusable
Figure 5
KHF 1050/PS440 Pilot's Guide