73-56-11 Series

Image of 73-56-11 T-Pass


73-56-11 Series, 380-420 MHz, T-Pass® Combiners
Broadband architecture of the T-Pass® circuit and coaxial cavities mitigates equipment obsolescence and facilitates ease of system reconfiguration when re-banding is necessary. Each System configured for optimum performance. Ideal for applications with minimal guard band between transmit and receive frequencies.


  1. -nn in model number represents the number of channels.
  2. These specifications are applicable to 380-420 MHz models.
  3. Models available with 5W/60W loads. Same specifications as 100W models, except load power.
  4. -MC option reduces maximum number of channels to twelve 6.625-inch channels per rack.
  5. -LR systems are tuned and tested on customer frequencies, then disassembled for shipping.
  6. Rack depth with cavity tuning rods at maximum frequency. Rod travel is approximately 5.1" (130 mm).




Expansion Channel Specifications

ModelFreq. Range (MHz)Isolator PowerIsolator LoadsExpansion Channel Model NumberStarter Channel Model Number
73-56A-11-xx380-400150 WSee note 3 above21-56A-11-xx-T21-56A-11-xx-TS
73-56B-11-xx400-420150 WSee note 3 above21-56B-11-xx-T21-56B-11-xx-TS

Note: "xx" in model number describes isolator and load configuration: 2B = 5 W/100 W

Typical Insertion Loss and Maximum Input Power a

Tx-Tx Separation Cavity LossMaximum Power
1 MHz-1.5 dB150 W
250 kHz-1.5 dB150 W
150 kHz-2 dB 125 W

Loss (dB) vs. No. of channels

Tx-Tx Separation 24812
1 MHz-2.4-2.6-2.9-3.1
250 kHz-2.9-3.8-4.4-4.7
150 kHz-3.6-4.8-5.6-6.0

Product Specifications 
Item No73-56-11 Series
Item Name380-420 MHz, T-Pass Combiner, 6.625" Cavity
Frequency Range380-420 MHz
Cavity Type and Diameter3/4-wave, 6.625” (168 mm)
Maximum Continuous Transmit Power125 W
Isolator Load Pwr Continuous5 W/100 W [Note 3]
Min Tx-Tx Separation at Cavity Loss150 kHz @ -2.0 dB
Typical Tx-Tx Isolation at Min Separation80 dB
Typical Antenna - Tx Isolation70 dB
Typical Tx Noise SuppressionDepends on cavity loss
Impedance Ω50
Maximum Input Return Loss - VSWR-20 dB (1.22:1)
Temperature Range-30 to +60 °C
Connectors - Input and AntennaN
MountingPeg Rack®
Mounting OptionsMC: 19” rackmount adapter plates, 17.5” high
LR: System supplied without Peg Rack® [Notes 4,5]
Maximum Channels - Rack15 [Note 4]
Dimensions65.25” x 24” x 37.5” (H x W x D) [Note 6]
(1659 x 610 x 953 mm)
Weight - Basic Single Channel37 lbs. (16.7 kg)
Weight - Expansion Channel Assy16 lbs. (7.2 kg)