Bird - The RF Experts
8730 Series
8730 Series, 10 kW, Water-Cooled Terminations
8730 Series

8730 Series, 10 kW, Water-Cooled Terminations
This series of water-cooled load resistors are designed as compact, low VSWR and non-radiating terminations for high-power transmitter/transmission line systems. The units generate almost no ambient heat, making installation space minimal and convenient, in any position. The RF power is converted to heat in the hollow resistive film load resistor and directly absorbed by the water flowing through it.

  • Broadband water-cooled load for long-term RF dissipation when heat must be efficiently transferred away from the area
  • Small size may be carried easily, used in any position and installed anywhere there is a source of potable water
  • Requires flow rate of 4 gallons (15.2 liters) per minute
8730 Series, Terminations
Model Freq. Range/VSWR Connectors Input Flange Weight
8730A 1.1 max. DC to 1 GHz 1-5/8" EIA, Flanged 3-1/2" Dia. (89 mm) 7 lbs. 14 oz. (3.6 kg)
8731 1.1 max. 1 KHz to 1 GHz (DC for continuity checks) 3-1/8" EIA, Flanged 5-3/16" Dia. (132 mm) 6 lbs. 10 oz. (3 kg)
8738A 1.1 max. DC to 1 GHz 3-1/8" EIA, Unflanged (Flush) n/a 6 lbs. (2.8 kg)

Need Replacement Parts?

product specifications:
Item No
8730 Series
Item Name
10 kW, Water-Cooled Terminations
Power Rating
10 kW continuous
Frequency Range and VSWR
See Model Matrix
Distilled Water (< 1KHz)
Distilled or Potable Water (>1KHz)
Water Temperture Range
+5 to +60°C
Water Flow Rate
4 gals./minute @ 5 °C to 6 gpm @ 60 °C
15.2 liters/minute @ 5 °C to 22.8 lpm @ 60 °C
Product Type
Operating Position
1/2" FPT or 3/4" hose
See Model Matrix
Input Flange Diameter
See Model Matrix
Black Powder Coat
14-3/4" L x 2-3/4" Dia.
375 x 70 mm
7 lbs. approx.
Model 8738A is recommended for areas with water quality conditions
Wall Mount Bracket