Kenwood TKR851 UHF FM Repeater Base Unit - 440-470Mhz - 25W / 240V - RRP £1,500
This item is in good used condition - General signs of use/ wear - some scuffs / scratches- Please refer to the pics.
In perfect working order, supplied with power leads.
Manufactures Description:
Kenwood TKR851 (TKR-851) UHF FM Repeater Base Unit kenwood_tkr851 / TKR851. The versatile TKR-851 is ready for deployment as a 16-user group conventional repeater, a simplex or full-duplex base station, or as the RF core of a trunking system. Advanced features such as the DSP audio processing, 5-Tone/DTMF over-the-air remote control and programmable auxiliary I/O’s combined with round-the-clock reliability add up to a superlative performing unit.
Features :
16 Channels.
Priority Scan.
6 Lighted PF Keys.
Front Panel Speaker.
Volume Control Knob.
Remote Control Inputs.
Front Microphone Jack.
Channel Up/Down PF Keys.
Voice Encryption Option Port.
Local Takeover/Remote PF Key.
Simplex or Full-Duplex Operation.
Power/Transmit/Busy LED Indicators.
2-Character Alphanumeric Channel Designator.
Antenna Switch for Simplex/Single Antenna Operation.
7-Segment 2-Character Channel & Scan LED Indicator.
Benefits:
Repeater Operation
The TKR-851 is “community repeater-ready” with the internal 16 QT/DQT group controller and programmable repeater functions such as 5-Tone access codes, CW Transmitter ID, Hang-Timer, Time-Out-Timer and Repeat Enable/Disable Key. The 1W-to-25W adjustable power output is ideal for on-site, exciter or repeater applications. (DC power supply not included).
Conventional or Trunking System Use
The TKR-751/851 can serve as the core element of any conventional or trunking repeater system. The basic internal conventional controller can be bypassed and an external conventional or trunking logic controller unit can be easily interfaced for advanced systems.
Simplex or Duplex Base Station Operation
The TKR-751/851 can be operated in simplex or fullduplex base station mode with up to 16 channels and priority scan. Internal solid state antenna switching is provided for simplex single-antenna base station operation. The accessory connectors provide DC or tone remote control interface.
5-Tone Selective Call, Repeater Open/Close
The built-in 5-Tone encoder/decoder (up to 3-frame) is compatible with a wide range of European protocols – EEA, EIA, CCIR, ZVEI, ZVEI-2, as well as the Kenwood tone format – while allowing detailed adjustment of parameters. There is also a 5-Tone decode function to open or close the repeater; this can be used in conjunction with QT/DQT.
5-Tone/DTMF Over-The-Air Remote Control
All front panel PF Key functions and AUX Input functions can be remotely activated and deactivated over-the-airvia 5-Tone or DTMF codes and provide an acknowledgement single tone or custom 5-Tone/DTMF transpond code. Also AUX outputs, upon activation and deactivation will encode unique 5-Tone/DTMF codes for monitoring and alarm purposes.
LED Display and Indicators
The enhanced 7-segment/2-character front panel LED provides a high-visibility 2-character alphanumeric channel designator and scan indicator for base station operation, a PLL unlock indicator and a PC program mode status for both base and repeater modes. Front panel dual-colour LED’s provide Transmit, Busy, Primary/Backup DC Power indications.
Backup Power Features
The Backup Battery Warning Tone transmits an overthe-air 5-second tone after DC supply has switched from “main” to “backup” power. Optionally a reminder Operation Tone can be transmitted while on backup power. These tones can be triggered when either DC power is connected to the backup DC input line or when the supplied voltage is lower than the programmed Power Supply Level DC voltage setting.
Windows Programming and Tuning Software
Windows compatible PC programming and tuning provides easy setup and alignment using the optional KPG-91D software and KPG-46 programming interface cable. The most common tuning parameters* are adjustable without opening the unit or using tools.
*Receiver helical resonator bandwidth, MCF waveform, and quadrature detector coil require manual tuning.
Specifications :
Antenna Impendance50
Sensitivity20 dB SINAD: 0.45 V
Adjacent Channel Sensitivity83 dB at 25 kHz
80 dB at 20 kHz
75 dB at 12.5 kHz
Intermodulation72 dB
Hum & NoiseWide: 50 dB at 25 kHz
48 dB at 20 kHz
45 dB at 12.5 kHz
Audio Output (Ext. Speaker)4 W (at 4, less than 5% distortion)
Surpious & Image Rejection90 dB
Audio Distortion (Ext. Speaker)Less than 2.5% at 1000 Hz
Band SpreadType 1: 5 MHz
Transmitter
Antenna Impedance50
RF Power OutputHigh: 25 W (default)
Low: 1 W (default)
(100% duty at 1-25 W)
APC Variable Range1-25 W
25 W adjustable to 1 W
Modulation Limiting5 kHz at 25 kHz
4 kHz at 20 kHz
2.5 kHz at 12.5 kHz
Spurious Emission-36 dBm 1 GHz
-30 dBm > 1 GHz
FM Noise (EIA)Wide: 50 dB at 5 kHz
48 dB at 4 kHz
45 dB at 2.5 kHz
Microphone Impendance600
Modulation DistortionType 1: Less than 3% at 1000 Hz
Band Spread30 MHz
Repeater Control
Signalling (simultaneously)Max. Number of Tones: 16
QT Decoder/EncoderTone/Frequency: 67.0-210.7 Hz (0.1 Hz step)
Decoder Response Time: 250 ms or less
Squelch Tail Elimination Time: 140 to 200 ms
Encoder Frequency Error: 0.3% or less
Sensitivity: SINAD 8 dB or less
DQT Decoder/EncoderDQT Code: 23 bits total: a 3-digit octal number (0-7, 12 bits) with error correction (11 bits)
Decoder Response Time: 250 ms or less
Turn-Off Code Transmission Time: 140 to 200 ms
Sensitivity: SINAD 8 dB or less
Time Out TimerOff to 30 min.
Repeat Hold TimeOff to 10 sec.
External Control
CWIDMax. Modulation: Max. deviation of 40% 10%
CW Tone Frequency: 400 Hz to 2000 Hz, (default 800 Hz)
Morse Code Speed: 5 to 30 words per minute, (default 20 WPM)
Max. Character Memory: Up to 32 characters (includes space)
CW MessageMax. Character: Up to 32 characters per bank (includes space)
Number of Banks: 8
Test ToneMax. Modulation: Max. deviation of 60%
Test Tone Frequency: 300 Hz to 3000 Hz (default 1000 Hz)
5-Tone StandardEEA, ZVEI, CCIR, ZVEI-2, EIA, Kenwood
General
Frequency RangeType 1: 440 - 470 MHz
Number of Channels16
Channel SpacingWide: 25, 20 kHz
Narrow: 12.5 kHz
(PLL channel stepping): (5, 6.25 kHz)
Operating Voltage13.2 V DC 15%
Current DrainStandby: 0.8 A
Standby with Power Save: 0.3 A
Receive: 1.2 A
Transmit/Receive: Less than 8 A
Duty CycleReceive: 100% - Transmit: 100%
Operating Temperature-30 C ~ +60 C
Dimensions (WxDxH)48.3 cm x 34.0 cm x 8.8 cm
Weight9.7 kg
Please note : This item will have a tamper / security sticker placed on it prior to dispatch, Unfortunately this is due to the every increasing number of scammers out there.
This item will be sent via a Tracked and signed for delivery service.
All items are security marked and serial numbers are recorded.

