Kenwood TM 255 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 53

12 MAINTENANCE)

xfi'fiWGfiWéMWéfiv

«rm
USING THE SOC PIN FOR RELAY OUTPUT

The function of the $00 pin located in the DATA
connector {page 6} can be changed to function as a
relay output.

1 Remove the lower case section {page 46}.

2 Move the slide switch located on the bottom rear of
the transceiver to the "RL" position.

In future, if you decide to use the Squelch Control
function, repeat this procedure but select the P80
position with the switch.

Page 56

. svm , . trobablebauss fiéfiectige Action .
Turning the RIT control The Receive Incremental Tuning Press [HIT] to turn ON the function. '33
has no affect on the function is turned OFF.
receive frfluency.
SSB audio quality is The IF SHIFT control is set incorrectly. Return the IF SHIFT control to the 33
very poor: the hlgh or center detent position.
low audio frequencies
are absent.
The frequency display The Transverter Frequency Display Turn OFF Menu 8, No. 76. 37
Is showing frequencies function is ON.
far outside the range
of the transceiver.
Scan doesn't work. Squelch is not set correctly. Adjust the SQL control to just eliminate 16
background noise.
Program Scan doesn't The Busy-Frequency Stop function is Turn ON Menu A, No. 03. 29
stop when signals are OFF.
received.
Band Scan only scans You are actually using Basic Scan Select a frequency that is outside the 31
a narrow range of because you have selected a VFO limits set for Basic Scan. then press
frequencies; the entire frequency within the limits for Basic [SCAN]. Or. you could erase the
band cannot be Scan and you have set the Basic Scan frequency limits stored in memory
scanned. Limits in memory channel 99. channel 99 by selecting that channel
and pressing [CLR] (2 5).
Scan Hold doesn't Busy-frequency Stop has not been Turn OFF Menu A, No. 3. 29
work even though turned OFF.
Menu B, No. 56 is ON.
Memory Scan doesn't 1 Data is not stored in 2 or more 1 Store frequency data in at least 2 24, 25
work. memory channels. memory channels.
2 All memory channels are locked out. 2 Unlock the memory channels you so
want to scan.
3 With Group Scan selected, the 3 Select All-channel Scan, or program 30, 24
channel you want to scan is in a the desired frequency within the
different group. current group.
The transceiver 1 The Automatic Power Off function is 1 Turn OFF the APO function via 37
switches OFF for no ON. Menu B, No. 58.
apparent "535° 2 No key entry was made for 180 2 Switch the power ON again. 37' 16
minutes when both APO and Tone
Alert were ON.
The transceiver does 1 Buttons are not being pressed in the 1 Review "CONVENTIONS ii
not respond correctly correct manner. FOLLOWED IN THIS MANUAL".
after you press button Different functions are selected
combinations per depending on how long a button is
instructions in this held down or whether a button is
manual. released before the next button is
pressed.etc.
2 The microprocessor and its memory 2 First review "MICROPROCESSOR 34
need resetting. RESET". Afterunderstanding what
data will be lost, do a Partial Reset.
If the problem remains, do a Full
Reset.
Continued

50

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].