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429-83H-01 Series
429-83H-01 Series, 792-824 MHz, Tower Top Amplifier System
429-83H-01 Series

429-83H-01 Series, 792-824 MHz, Tower Top Amplifier System

The compact Tower-Top Amplifier (TTA) system is a high performance, quadrature-coupled low noise amplifier (LNA) 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.

The TTA system consists of two components: the Tower-Top Amplifier mounted close to the antenna and the Receiver Multicoupler base unit. 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.

Two independent LNA's, each powered by separate bias circuits, provides component redundancy as well as excellent intermodulation (IM) performance. Microprocessor-controlled fault detection circuitry provides continuous monitoring and switching of each quad-LNA while sending operational data to the base unit for at-a-glance status reporting and form C contact alarm switching.

For AISG/EIA-485 data communications between the TTA and base control unit, a custom PolyPhaserTM lightning protector and a CAT-5E cable are installed at the transmission lines building entry-point ground plate. The surge protector not only passes the DC current that powers the TTA but also generates the low frequency subcarrier for AISG/EIA-485. If the data cable is damaged, removed or not installed, the TTA will continue to operate however, the status and alarm functions will not be available at the base. For testing and diagnosing problems on the main receive line, a test transmission line is required. The system will continue to operate if the test line is damaged or not installed however, an alarm will be continuously set.

System Specifications

13 dB net gain and maximum 6 dB transmission line loss assumed

  • Bandwidth: 792-824 MHz
  • System Noise Figure: 3.4 dB Typ, 4.0 dB Max
  • 3rd Order IIP: > 15dBm
  • TTA Net Gain: Fully settable by electronic attenuator
  • Filter Rejection: 110 dB min, 120 dB nominal at 776 and 851 MHz
  • Net Weight: 30.5 lbs for TTA + MCU
  • Ship Weight: 42 lbs.
Model Numbers Description Power Requirements
429-83H-01-T TTA, 792-824 MHz, Tower Top Box Only -
429-83H-01-M Receiver Multicoupler for TTA, 16-port, 792-824 MHz AC
429-83H-01-M-48 Receiver Multicoupler for TTA, 16-port, 792-824 MHz DC

Spec. Legend
[TTA] = Tower Top Amplifier
[MCU] = Multicoupler Control Unit

Optional Filters:
  • Optional Filters are available to provide a narrower window ahead of the receiver multicoupler in order to achieve better selectivity for the system. (See "Compatible Devices" under the specifications table for filter selection)
  • Please specify sub-band frequency when ordering
429-83H-01 Series, 792-824 MHz, Tower Top Amplifier System
429-83H-01 Series
product specifications:
Item No
429-83H-01 Series
Item Name
792-824 MHz, Tower Top Amplifier System
TTA---Frequency Range
792-824 MHz
TTA---Net Gain
22 dB (typ.)
TTA---Noise Figure
3.2 dB (typ.)
3.5 dB (max.)
TTA---Backup Amplifier Switching
Solid State RF Switch
TTA---Integrated Test Port Isolation
45 dB (typ.)
Type:  7-pole TEM Bandpass with Cross-Coupling
Loss:  < 0.8 dB
Rejection:  > 60 dB @ 776 and 851 MHz
Type:  2-Stage Quadrature integrated into filter
Gain:  26 dB
Noise Figure:  1.2 dB
3rd Order Input IP:  +18 dBm
TTA---Impedance Ω
50 Ohms
TTA---Antenna Port VSWR
TTA---Power Requirements
12 VDC @ 1.25 A
TTA---Lightning Protection
Impulse suppressor on all external connectors
TTA---Operating Temperature
-30 to +60°C
Modified NEMA 4X Stainless Steel Weather Resistant
N (Female)
TTA---Dimensions H x W x D
(not including mounting tabs or connectors)
18" x 6" x 6"
457 x 152 x 152 mm
TTA---Net Weight
20 lbs (9.1 kg)
MCU---Frequency Range
792-824 MHz
MCU--- Multicoupler Net-Gain
+1 dB typ; 0 dB min
MCU---Distribution Amp
Type:  Quadrature-Coupled Dual Stage
Gain:  23 dB
Noise Figure:  4 dB
1 dB Compression Point:  +27 dBm
3rd Order Input IP:  +46 dBm
MCU---Number of Outputs - Split Loss
16 or 32 / 18 dB
MCU---Impedence Ω
50 Ohms
< 2:1
To TTA:  N (Female)
To BTS:  BNC (Female)
Test Port Input:  BNC (Female)
MCU---Net Gain Electronic Attenuator
0-15.5 dB in 0.5 dB steps
MCU---Distribution Amp Electronic Attenuator
0~3 dB in 0.5 dB steps
MCU---Alarm and Warning Contacts
Two Form C Contacts (Nominal 2A @ 30 VDC or 0.5A @ 125 VAC)
MCU---Power Requirements
90-240 VAC 50/60 Hz
180 mA @ 120 V
(current draw is for base deck only, not including the power needed to run the tower top box)
MCU---Operating Temperature
(at non-condensing humidity)
0 to +50°C
Standard EIA 19" Rack Mounting
MCU---Dimensions H x W x D
1 RU x 19" x 14"
(38 x 483 x 356 mm)
10.5 lbs (4.8 kg)
compatible devices:
792-806 MHz, Preselector
792-806 MHz, Preselector
792-806 MHz, Preselector
792-806 MHz, Preselector
806-824 MHz, Preselector
806-824 MHz, Preselector
806-824 MHz, Preselector
806-824 MHz, Preselector