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434B Series
434 Series, Mini AutoQuad Tower Top Amplifier System
434B Series

434B Mission Critical Series, Auto Quad Tower-Top Amplifier (TTA) System is a high performance, quadrature-coupled low noise amplifier (LNA). The TTA increases receive sensitivity, reduces transmit signal interference and can make all the difference in Mission Critical Communications.

The TTA operates independently, monitoring LNA current and automatically switching to a redundant LNA if needed. Status reporting is accomplished via AISG compliant telemetry between the controlling processor in the Tower Box and the base control unit. The base control unit has an on board AISG modem device which does not require the use of an external data cable. This telemetry does not interfere with RF Signals in any way and communicates the LNA currents, temperature and operational status to the base control unit LCD display. Test modes and manual switching between LNA's is also accomplished by way of the telemetry system.

The TTA consists of two components: the tower top amplifier mounted close to the antenna and the control unit. The control unit is available in two styles, either with or without a receiver multicoupler. In order to reduce the size of the TTA and simultaneously provide 120 dB of isolation of a TX carrier, filtering has been split between the TTA and the base unit.

Industry leading TTA amplifier linearity guarantees superior immunity to intermodulation interference.

  • All tower top ports protected by internal surge suppressors.
  • Two independent Quadrature Coupled LNA's in the tower top assembly provides the redundancy needed to ensure maximum uptime.
  • Microprocessors continuously monitor amplifiers and will switch tower top LNA’s if needed.
  • Ethernet
  • Multiple Real-Time Status and Alarm Annunciation Methods:
  • - Secure SNMP (v3.0) Trap Messaging (compatible with most SNMP Managers)
  • - Form-C contacts
  • - Front Panel Status Indicators
  • Wind loading is reduced due to the small enclosure size.
  • Available with a 16 Port Receive Multicoupler Unit.
  • Expandable as needed to 32, 40 or 48 ports.

The TTA is designed to increase the performance of a Base Transceiver Station (BTS) while ensuring reliable communications for critical Public Safety applications. This increase in sensitivity can make up for the imbalance between mobile and handheld users in critical systems.

Model Number Description Power Required
434B-83H-01-T TTA, Mini AutoQuad, 792-824 MHz, Tower Box -
434B-83H-01-M-110 Multicoupler Unit (MCU), 16-port, 792-824 MHz used with 434B-83H-01-T AC
434B-83H-01-M-4 Multicoupler Unit (MCU), 16-port, 792-824 MHz, used with 434B-83H-01-T -48
434B-94D-01-T TTA, Mini AutoQuad, 896-902 MHz, Tower Top Box Only  
434B-94D-01-M-110 Multicoupler Unit (MCU), 16-port, 896-902 MHz, used with 434B-94D-01-T AC
434B-94D-01-M-48 Multicoupler Unit (MCU), 16-port, 896-902 MHz, used with 434B-94D-01-T  -48

Tower Top Amplifier will function up to 70°C without shutting down however, the specifications are not guaranteed outside the rated temperature range. MCU specifications values are typical unless noted otherwise.

  • TTA = Tower To Amplifier
  • MCU = Multicoupler Unit

#Note: See the datasheet for Optional Products

Mini Tower Top Amplifier Filtering | 434-435 Series TTA Systems

A steep skirted TEM bandpass filter in the tower box augmented by a ceramic filter in the base unit provide a selective 32 MHz system window.

434B 900 MHz Curve
434 Series, Mini AutoQuad Tower Top Amplifier System
434B Series
product specifications:
Item No
434B Series
Item Name
Mission Critical Series, Auto Quad Tower-Top Amplifier System
Frequency Band
700-800 MHz, 900 MHz
Net Gain
15.0 Typ.
110 dB nominal at 776 and 851 MHz
Noise Figure
2.9 dB Typ.
Total Power Dissipation
17 W
TTA---Frequency Band
700/800 MHz - 792-824 MHz< /br>900 MHz - 896-902 MHz
TTA---Preselector Included
TTA---Preselector Frequency Range
792-824 MHz, 896-902 MHz
TTA---Type of Amplifier
Quadrature Coupled (Redundant)
TTA---Amplifier Switching
TTA---Type of Amplifier Switch
Solid State RF Switch
TTA Gain---Input to output of TTA
22.5 dB Typ.
TTA---Noise Figure
2.9 dB Typ.
>43 dBm Typ.
TTA---Return Loss of all RF Ports
> 14 dB
TTA---Power Requirements
Power derived from Rx Cable
TTA----Operating Temperture Range
-30°C to 60° C
TTA---Amplifier Redundancy
Automatic change - over
TTA---Lightning Protection
Impulse suppressor on all external ports
TTA---Test Port Included
TTA---Coupling Test Port--Test In-Amp In
30 dB
TTA---50 Ohm Termination Test
Controlled by base unit
TTA---Type of RF Test Switching
Solid State RF Switch
TTA---Bypass Test Mode
Controlled by base unit
Weather resistant housing designed to NEMA Standards
TTA---700 and 800 Dimensions and Net Weight
8.84" x 5.77" x 6.04" / 8 lbs
TTA---900 Dimensions and Net Weight
7.25" x 11.25" x 11.25" / 14.28 lbs
MCU---Frequency Band
792-824 MHz, 869-902 MHz
MCU---Net Gain or Loss--RMC In to RX Out
+1 dB Typ
MCU---Number of Outputs Ports
16 expandable to 48
MCU---TTA Connector
MCU---Receiver Connector
MCU---RX-RX Port Isolation
>20 dB (min.)
MCU---Test Port Input
BNC-Female (Front of RMC)
MCU---Test Port Output
N-Female (Rear of RMC)
MCU---Net Gain Electronic Attenuator
15 dB in 0.5 dB steps (6 dB default)
MCU---Alarm Contacts
Form-C contacts
MCU---Ethernet Port
RJ45 (Front panel access)
MCU---Power Requirements
90-240 VAC @ 50/60 Hz or -48 VDC
MCU---Operating Temperature
0°C to +50°C
Standard EIA 19” Rack Mounting
MCU---700 and 800 Dimensions and Net Weight
1 RU x 19" x 14"(45 x 483 x 356 mm) / 11.5 lbs
MCU---900 Dimensions and Net Weight
1.75" x 19" x 12.25" / 9.92 lbs