TM 11-5820-890-10-1
OPERATIONAL NOTES
PREFERRED ANTENNA CONFIGURATION
The recommended antenna configuration for a retransmit station is two OE-254
antennas. OE-254 antennas should be fully extended and separated to their maxi-
mum distances (based on site constraints). Under no circumstances should the
OE-254 antennas be positioned less than 75 feet apart. (However, if more than
one retransmit station Is located within a confined area, a special antenna configu-
ration may be required.)
ALTERNATE ANTENNA CONFIGURATION
Never use two vehicular antennas for FH retransmit. However, two vehicular an-
tennas may be used for SC retransmit.
A vehicular antenna may be used with an OE-254 antenna (fully extended) pro-
vided the OE-254 antenna is used for the retransmit link which is the longest,
When using a vehicular antenna with an OE-254 antenna, it is important to note
that the preferred distance between antennas is 50 feet. The minimum antenna
separation (base to base) is 15 feet.
SITE SELECTION
The retransmit station must be located on top of a hill (or highest point).
Both outstations must be within the retransmit station’s line-of-sight (LOS). LOS
is defined as a clear path (no barriers such as mountains, tall buildings, etc.)
between the retransmit station and the outstations. Refer to the Illustration on
page 4-21.
OPERATIONAL REMINDERS
Refer to the SOI for authorized hopset(s).
Make sure RF switch is set to the lowest possible setting for good communication.
F1 represents the frequency (hopset) between radios A and C. F2 represents the
frequency (hopset) between radios B and D.
Radio link A and C should have a different hopset than radio link B and D during
FH retransmit. However, if only one hopset is available, it may be used for both
links provided the net ID’s are different, antenna configuration notes are followed,
and each radio sets RF switch to lowest possible setting for good communication.
A COMSEC key is not needed to retransmit secure signals, but it Is needed for
monitoring.
Radios at the retransmit site (radios C and D) must have COMSEC switch set to
once retransmit operation has begun. However, communication is secure
(based on the status of the outstation).
Cue and ERF signals will not pass through a retransmit station.
4-24
