Kenwood TM 455 E Owners Manual

Page 2

Models Covered by this Manual:

- TM-255A: 144 MHz All Mode Transceiver
(U.S.A./ Canada/ General)

. TM-255E: 144 MHz All Mode Transceiver
(Europe)

TM-455A: 430 MHz All Mode Transceiver
(U.S.A./ Canada)

. TM-4SSE: 430 MHz All Mode Transceiver
(Europe)

Notice to the user:

One or more at the following statements may be
applicable to this equipment.

FCC WARNING

This equipment generates or uses radio frequency energy.
Changes or modifications to this equipment may cause harmful
interference unless the modifications are expressly approved in
the instruction manual. The user could lose the authority to
operate this equipment if an unauthorized change or modification
is made.

INFORMATION TO THE DIGITAL DEVICE USER REQUIRED
BY THE FCC

This equipment has been tested and lound to comply wim the
limits fora Class B digital device, pursuant to Part 15 cf the FCC
Rules. These limits are designed to provide reasonable
protection againstharmtul interference in a residential installation.

This equipment generates, uses and can generate radio
frequency energy and. if not installed and used in accordance
with the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that the
interference will not occur in a particular installation. If this
equtprnent does cause harmful interference to radio or television
reception, which can be determined by turning the equipment of!
and on. the user is encouraged to try to correct the intefierence
by one or more of the lot/owing measures:

. Heorient or relocate the receian antenna
. increase the separation between the equipment and receiver.

' Connect the equipment to an outlet on a circuit diltereht from
that to which the receiver is connected.

- Consult the dealer [or technical assistance.

Page 57

13 TROUBLESHOOTING

wees

Problem Symptom g Probable Cause Corrective Action 7 , " my,
Packet operation 1 Physical connections between the 1 Pie-check all connections using this 5
results in no connects transceiver, computer, and TNC are manual, your TNC manual and your
with other stations. incorrect. or software settings in the computer hardware manual as

TNC are wrong. references.
2 Different transmit and receive 2 Store the desired operating 24
frequencies are being used. You frequency in a memory channel
must use the same transmit and using the Simplex Channel Storage"
receive frequency for packet. procedure.
3 The modulation level from the TNC is 3 Adjust the TNC modulation level per 22
incorrect. instructions in PACKET
OPERATION" and your TNC
manual.
4 The 9600 bps rate setting is set 4 Refer to "PACKET OPERATION" for 22
incorrectly. information on setting Menu B,
No. 77 correctly.
5 The transmitted signal is too weak. 5 Reorient your antenna or increase -
your antenna gain to improve your
signal strength at the other station.
6 Tone, CTCSS. DTSS, or Page are 6 Turn OFF Tone, CTCSS, DTSS, and 20,
ON. Page. Set the noise squelch 40,
threshold as you would for voice 41,
communications. 43, 16

y ....._

Page 64

.m-

Rapear

A station, usually installed in a central location at a
high elevation, designed to receive and re-transmit
signals. The purpose of a repeater is to increase the
receive and transmit range of stations able to access
the repeater.

Reset (Initialization)

The act of restarting the transceiver microcomputer.
Depending on the type of reset done. some or all
memory may be erased and set to default values. A
reset can be done as a last resort when the
transceiver appears to be malfunctioning.

Simplex channel

Refers to a communications channel where the
receive and transmit frequencies are equal.

Split channel

Refers to a communications channel where the
receive and transmit frequencies are not equal.
Squelch

A function that automatically mutes a receivers
speaker output when no receive signal is present.
Squelch Hang Time

The time that the squelch remains open after a carrier
drops out.

Squelch threshold level

The receive level at which a receiver's speaker output
is muted. This level is usually adjustable, either
manually or automatically by the transceiver
microcomputer.

Standard offset

Refers to a transmit frequency offset used to access
repeaters that is equal to the amount and direction
stipulated by existing band plans for a particular
region. See "Transmit offset".

Station Page code

When using Page, each station must be assigned a
unique code that no other station uses. This is your
Station code. Only the squelch of the targeted station
will open when a transmission with this Station code is
made. See "Group code".

Subaudible Tune

A lowlrequency signal superimposed by a transmitter
on a transmitted signal for the purpose of accessmg
some types of repeaters.

58

'9W'R3W

(s an my wave ra 0)

An antenna that is not correctly matched in
impedance with a transmission line and transmitter
will reflect some portion of the transmittedsignal back
toward the transmitter. This causes a standing wave
pattern to develop. The ratio of maximum to minimum
voltage (VSWR) on the transmission line when such a
condition exists is commonly referred to as the SWR.

Tone frequency
See "Subaudible Tone".

Transmit offset (shift)

All Amateur voice repeaters operate on separate
transmit and receive frequencies. Transmit offset is
the amount that a transmit frequency is different from
a receive frequency. See "Transmit offset direction".

Transmit offset (shift) direction

Refers to the direction. either plus (+) or minus (-),
that a transmit frequency is with respect to a receive
frequency. Both the direction and amount of offset
must be selected correctly to access a repeater. See
"Transmit offset".

VFO (variable frequency oscillator) mode

The mode that allows any individual frequency to be
selected within the range of the VFO only restricted by
frequency step limitations. When in VFO mode,
frequencies are selected using the Tuning control or
microphone [UP]/[DWN].