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8251 Series
8251 Series, 1 kW, Oil-Cooled Terminations
8251 Series

8251 Series, 1 kW, Oil-Cooled Termination is portable, self-contained general purpose 50 ohm coaxial transmission line terminations requiring no outside power source or additional equipment. The loads are Oil-assisted convection cooling for safe, continuous operation up to 1000W full rated power. They provide accurate, dependable, and practically nonreflective termination for testing and adjusting transmitters under nonradiating conditions. The load consists essentially of a cylindrical film type resistor immersed in a dielectric coolant. The resistor, individually selected for its accuracy, is enclosed in a special tapered housing which provides a linear reduction in surge impedance directly proportional to the distance along the resistor.

  • This series has includes 8251D and 8251D7-16 models for
    Digital Broadcast VSWR = 1.065 max., 470-860 MHz
8251 Series, Terminations
Model Connector
8251 LC connector installed and an additional QC-N connector for lower-power testing
8251N QC-N connector for lower-power testing.
8251D 1-5/8" EIA, Flanged
8251D7-16 7/16-DIN (F)

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product specifications:
Item No
8251 Series
Item Name
1 kW, Oil-Cooled Terminations
Power Rating
1000 W continuous
Frequency Range and VSWR
DC - 1 GHz @ 1.1 max.
1 GHz - 2 GHz @ 1.25 max.
2 GHz to 2.4 @ 1.3 max.
1.065 max., 470-860 MHz for "D" Models
Temperture Range
-40 to +45 °C
1.1 gal. (4.1 liters) Silicon Oil
Product Type
Operating Position
Horizontal Only
See Model Matrix
Gray Powder Coat
17-29/32" x 5-15/16" x 8-1/2" (L x W x H)
455 x 151 x 216 mm
25 lbs., 8 oz. (11.5 kg)