Kenwood TKR-840 Leaflet

The 25-pin D-Sub controller interface port also provides six
AUX Outputs and three AUX Inputs. The AUX Outputs are soft-
ware programmable with functions such as PLL unlock,
transmit sense, supply voltage sense, RSSI, exciter tempera-
ture, etc., for site monitoring equipment and backup power and
environmental systems. These AUX Outputs are programmable
for active high or low and can be controlled by the AUX Input
ports using signals from remote console termination panels 
or site control equipment. The AUX Inputs are programmable
active high or low and can be programmed for any front panel
PF function, perform direct channel access or AUX Output port
control (turned on, turned off or toggled on/off the AUX output).
Each AUX input has a “macro” capability and can control up 
to three AUX Output ports simultaneously. The 12-pin accessory
connector has 5 macro-capable AUX I/O ports that are 
programmable for either AUX Input or Output functions. 

The 100% duty cycle, 1.5 PPM high stability RF power output 

is continuously adjustable from a 100 mw to 5 W. The filtered
impedance-matched output is the heart of the TKR-7400/8400
Series systems as the exciter stage for high-power systems or
for direct output low power applications.

Flash memory permits updates, advanced feature sets and 
system architectural changes to be made electronically without
ever opening the unit. This means faster modifications for 
system operators and less downtime for users.

The LED indicators provide clear
system status information at a
glance, including transmit, receive, external standard input and
power. If the transmitter or receiver synthesizer become
unlocked, the LEDs flash for quick problem assessment.

The TKR-740/840 are programmable for wide/narrow channel
spacing* on a per channel basis [TKR-740: 25 (30) kHz wide/
12.5 (15) kHz narrow; TKR-840: 25 kHz wide /12.5 kHz 
narrow]. The enhanced synthesizer PLL channel step 
programmability accommodates channel allocations now and
in the future. 

*Both models operate with no less than 25 kHz wide and 12.5 kHz narrow channel
bandwidth.

The 32 channel simplex/full-duplex base mode provides 
a perfect platform for high-end conventional base station 
systems. The priority scan capability permits multiple channel
usage full-time or on command while monitoring a primary
dispatch channel. The remote control and programmable
ports permit full dispatch console access to all base station
controls and functions. The front panel programmable 
function-keys (PF keys) with status LED’s provide full
equipment room/on-site control and can be concealed and/
or disabled all together. The two-digit LED display provides 
channel display, operational status, programming status and
fault indications.

The TKR-740/840 repeater systems posses all the remote
control, programmability and site control attributes as in base
mode. Front panel PF key functions as Takeover (remote 
disable), TX Disable and Repeat On/Off can be assigned for
site setup and maintenance use. 

The internal conventional repeater mode supports up to 16
user groups (16 QT/DQT) using Digital Signal Processing tech-
niques. This also supports the traditional CW-ID, time-out
timer, hang time, reverse burst squelch tail elimination, etc.,
repeater operations. The internal controller can be bypassed
and an external conventional or trunking logic controller
option used in its place.

There are 16 programmable multi-tone/code tables each with
16 QT/DQT tone/code pairs that can be assigned on 
a per channel basis. This provides multi-channel base 
stations up to 16 users groups per channel. This feature can
also be used for fail-safe standby base or repeater units that
can be activated into use in the even of a system failure
(additional fail-safe systems engineering and 
components required). 

The low profile design saves site rack for other system 
components on multi-channel base systems and repeaters.
The all metal encased panels and die-cast chassis with 
integrated heat sink are key to the TKR-740/840’s durability,
superior service level and reduced weight. The unit is sealed
to provide long-term protection from dust, moisture and for-
eign ingress even in the most abusive operating conditions.

The TKR-740/840 can be programmed/tuned quickly and effi-
ciently without ever opening the case. Programming/tuning
can be done though front panel microphone/handset jack with
the KPG-47D software, KPG-46 interface cable, and any PC-
compatible computer. The same can also be done via the rear
panel 25-pin connector. The PC tuning parameters available
are shown below:

The internal oscillator already provides an excellent ± 1.5
PPM stability figure, but for more demanding applications
such as simulcast or paging systems, you can inject an exter-
nal oscillator standard to obtain a much higher stability factor.
The “REF” LED on the front panel changes from green to red
when the external signal is applied.

The built-in front panel speaker provides excellent audio for
on-site monitoring and can be controlled via the volume
on/off knob.  The TEST switch allows you to activate the trans-
mitter and the supplied hand microphone for air checks and
the Intercom function. 

❚ COMPANDED AUDIO

❚ EIGHT CW MESSAGE MEMORIES 

❚ VOTER TONE GENERATION 

❚ DIGITAL PAGING ENCODER INPUT 

(bi-level type; e.g. POCSAG)

❚ VOICE SCRAMBLER PORT/CONTROL

❚ Squelch (Analog/RSSI)
❚ RX audio signal output (RA)
❚ RX detector signal output (RD)
❚ RF output power
❚ Maximum Deviation
❚ TX audio input (TA)
❚ Remote TX audio input (RTA)

❚ Signaling Deviation (TD)
❚ Signaling balance
❚ QT deviation
❚ DQT deviation
❚ Test tone deviation
❚ CW ID deviation
❚ Repeat gain 
❚ Voting tone level
❚ Digital pager shift level
❚ Digital pager wave balance

Manual tuning is available for the following settings: RX
helical resonator block bandwidth, MCF waveform, Quad
detector coil, and MIC sensitivity.

TKR740_US.QXD  12/2/99 10:28 AM  Page 1