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73-38-01 Series
T-Pass, Transmit Combiners
73-38-01 Series

73-38-01 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
  • 73-38-01-2B-nn
  • 73-38-01-2D-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).
73-38-01 Series Systems (6.625" 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 -2.0 dB 135 W
75 kHz -2.5 dB 115 W

Loss (dB) vs. No. of channels
Tx-Tx Sepration 2 4 12
1 MHz -2.6 -2.7 -3.3
250 kHz -3.3 -4.5 -5.7
100 kHz -3.6 -4.5 -5.5
75 kHz -4.3 -5.4 -6.7

Note: 50 kHz - Use 10" cavities at this separation

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T-Pass, Transmit Combiners
73-38-01 Series
product specifications:
Item No
73-38-01 Series
Item Name
132-174 MHz, T-Pass Combiner, 6.625" Cavity
Frequency Range
132-174 MHz
Cavity Type and Diameter
Quarterwave, 6.625” (168 mm)
Maximum Continuous Transmit Power
See Model Matrix
Isolator Load Pwr Continuous
73-38-01-2B-nn: 5 W/25 W [Note 3]
73-38-01-2D-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
15 [Note 4]
Dimensions
79.5" x 24" x 36.9" (H x W x D) [Note 6]
(1659 x 610 x 937 mm)
Weight - Basic Single Channel
73-38-01-2B-nn: 33 lbs. (17.5 kg)
73-38-01-2D-nn: 37 lbs. (17.7 kg)
Weight - Expansion Channel Assy
73-38-01-2B-nn: 15 lbs. (6.8 kg)
73-38-01-2D-nn: 16 lbs. (7.2 kg)
accessories:
93-00 Series
T-Pass, Transmit Combiner Racks