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73-38-05 Series
T-Pass, Transmit Combiners
73-38-05 Series

73-38-05 Series, 132-174 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.

Models
  • 73-38-05-2B-nn
  • 73-38-05-2D-nn
  1. -nn in model number represents the number of channels.
  2. Consult factory on T-Pass multicouplers for frequencies below 174 MHz.
  3. Models available with 5W/60W loads. Same specifications as 25W and 100W models, except load power.
  4. -MC option reduces maximum number of channels to ten 10-inch or 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 5.4” (137 mm).
73-38-05 Series Systems (10" Cavity Diameter)
Tx-Tx Sepration Cavity Loss Maximum Power
1 MHz -1.5 dB 150 W
250 kHz -1.5 dB 150 W
100 kHz -1.5 dB 150 W
75 kHz -2.0 dB 150 W
50 kHz -2.5 dB 130 W

Loss (dB) vs. No. of channels
Tx-Tx Sepration 2 4 12
1 MHz -2.6 -2.7 -3.1
250 kHz -2.9 -3.4 -4.0
100 kHz -3.0 -3.7 -4.5
75 kHz -3.5 -4.2 -5.0
50 kHz -4.1 -5.0 -6.1
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T-Pass, Transmit Combiners
73-38-05 Series
product specifications:
Item No
73-38-05 Series
Item Name
132-174 MHz, T-Pass Combiner, 10" Cavity
Frequency Range
132-174 MHz
Cavity Type and Diameter
Quarterwave, 10” (254 mm)
Maximum Continuous Transmit Power
See Model Matrix
Isolator Load Pwr Continuous
73-38-05-2B-nn: 5 W/25 W [Note 3]
73-38-05-2D-nn: 5 W/100 W
Min Tx-Tx Separation at Cavity Loss
125 kHz @ -1.5 dB
75 kHz @ -2.5 dB
Typical Tx-Tx Isolation at Min Separation
Typical Antenna - Tx Isolation
Typical Tx Noise Suppression
Depends on cavity loss
Impedance Ω
50
Maximum Input Return Loss - VSWR
-20 dB (1.22:1)
Temperature Range
-30 to +60 °C
Connectors - Input and Antenna
N
Mounting
Peg Rack®
Mounting Options
MC:19” rackmount adapter plates, 17.5” high
LR: System supplied without Peg Rack® [Notes 4,5]
Maximum Channels - Rack
12 [Note 4]
Dimensions
79.5" (H) x 24" (W) x 26.9" (D) [Note 6]
(2019 x 610 x 937 mm)
Weight - Basic Single Channel
73-38-05-2B-nn: 41 lbs. (18.6 kg)
73-38-05-2D-nn: 42 lbs. (19 kg)
Weight - Expansion Channel Assy
73-38-05-2B-nn: 19 lbs. (8.6 kg)
73-38-05-2D-nn: 20 lbs. (9.1 kg)
accessories:
93-00 Series
T-Pass, Transmit Combiner Racks