TM 11-5820-890-10-3
JAMMING AND ANTIJAMMING
JAMMING.
Jamming is the intentional transmission of signals that interrupts your ability to receive needed signals.
Interference is the accidental transmission of signals that also interrupts your ability to receive needed signals. If you are
being jammed, it might sound like strong static, misleading signals, or random noise; or the net may be quiet with no
signals heard. These signals depend upon the type of jamming signals and whether your net is operating in single channel
(SC) or frequency hopping (FH) mode. The source of jamming could be power generators, radar sets, high power HF
radio sets, or intentional enemy jammers. Use the following table to determine the possible source of jamming and the
corrective actions.
SINGLE CHANNEL OPERATIONS.
SYMPTOM
POSSIBILITIES
ACTION
SIG marker is lit and
(1)
You have a bad
(1)
Try to free-up the stuck
showing a signal high-
handset if you dis-
mike by pressing push-to-
er than 3 You hear
connect the hand-
talk 2 or 3 times Remove
no traffic or noise and
set and the lighted
faulty handset and replace
you are not transmitting
signal goes away
with one that is good.
(stuck or “hot”
mike).
(2)
You are being
(2)
Change your tactical lo-
jammed if you set
cationTry to mask your RT/
RT FCTN switch to
antenna by placing hills.
SQ OFF and hear
rocks, buildings, etc be-
strong static or ran-
tween you and the enemy.
dom noise You can
Notify your supervisor and
confirm this by dis-
prepare a MUI feeder report.
connecting the an-
tenna (MP) or an-
tenna cable (vehic-
ular) The SIG mark-
er will drop and the
noise will go away
or be reduced.
(3)
You may have a
(3)
Set RT FCTN switch to
faulty or “locked-up"
OFF ; then to SQ ON If
RT if you try remov-
problem still exists, contact
ing the handset and
unit maintenance.
the antenna (MP) or
antenna cable (vehic-
ular) and the SIG
marker remains high-
er than 3.
2-47
