64
T2000 Radio Encryption
M2259-00-200-812
Encrypted Radio Programming and Service Manual
Copyright TEL
5.7
T2000 Fault Finding
Diagnosis TIP
If unsure whether a radio with simple inversion encryption is in
encrypt
or
clear
mode: while in
standby (without any incoming signal), hit a keypad or function key to produce an audible beep.
If the radio is in
encrypt
mode, the beep will be a much higher frequency than normal.
Symptom
Cause
Action
Radio transmits regularly -
goes into emergency mode
Audio not operating
Radio stopped working after
it was dropped.
Module not squarely in connector
Re-plug connector to module
(radio will need to be opened)
Receives okay, but no
transmit audio.
Module may not be receiving PTT
Check PTT links.
Encryption on/off button
only changes encryption
state every second press
Module or radio programmed for
level-sensitive when it should be
edge-sensitive.
Reprogram encryption
module or radio.
T2000 has encryption on
when Aux light is out and
vice versa
Module or radio programmed for
wrong Mode polarity
Reprogram module.
Module does not de-crypt
audio.
Module has been programmed
differently to the rest of the fleet.
Reprogram with correct
settings.
Module acknowledges its
ID, but not accept any other
commands.(Transcrypt
modules only)
Module programmed with wrong
programmer and different Master
code.
Reprogram with correct
programmer - will need a
‘Force Download’. (See
Transcrypt Manual)
Module acknowledges its
ID, but not accept any other
commands. Force
download does not fix.
Module may be damaged or have
failed.
Replace with a new module.
Radio will not power up
properly, display blank.
Flex-edge connectors may not be
correctly plugged
Module faulty.
Replace module.
Poor audio quality
Module links set for wrong radio type.
Set links according to the
manuals.
Audio sounds very muffled
(Midian modules only)
Inversion module has very low
inversion frequency.
Program module to a higher
frequency.
Audio sounds very “thin”.
(Midian modules only)
Inversion module has very high
inversion frequency.
Program module to a lower
frequency.
Audio sounds squeaky or
croaky. (Midian modules
only)
Transmit and receive inversion
frequencies are different.
Ensure both radios are using
same frequency. If problem
still exists, reprogram module
Receiving radio fails to
decode sync pulse, audio is
unintelligible for several
seconds then comes right.
(Transcrypt only)
System delay set too short
Reprogram module, or
consider if CTCSS can be
removed from some parts of
radio system.
Radio confidence and alert
tones rapidly varying tones.
Not a fault - occurs when alert tones are injected before decrypting
process in inversion or hopping code module in encrypt mode.
