Bird 8890 Termaline RF Load Resistor 2500W

The Bird 8890 is a series of high-performance, oil-cooled RF terminations designed for precise signal control and power dissipation in demanding communication systems. These devices are engineered for laboratory and field applications requiring accurate and reliable RF load termination. The Bird 8890 series is available in various configurations, including models capable of handling up to 2.5 kW and 5 kW of continuous RF power.

### Technical Specifications

**General Parameters:**
* **Type:** Coaxial Termination (RF Load)
* **Impedance:** 50 Ohms
* **Cooling Method:** Oil-dielectric, convection cooling. Models are also available with integrated forced-air cooling via a built-in blower for higher power ratings.
* **Construction:** Rugged, self-contained design. Features a precision-tapered film resistor immersed in dielectric coolant, housed within a cylindrical coaxial structure with radiator fins for heat dissipation.
* **Mounting:** Designed for freestanding use or fixed installation via mounting brackets on the front and rear faces.

**Electrical Specifications:**
* **Power Handling:**
* 2.5 kW continuous RF power for the 8890-300 series.
* 5 kW continuous RF power for the 8890-315 and 8890-320 series (with integrated forced-air cooling).
* Note: Maximum power can be 1,250 W when the blower is not running for models equipped with a blower.
* **Frequency Range:**
* DC to 2.4 GHz for many models.
* DC to 1 GHz for the 8890-300 series.
* Specific models designated “D” are for use in the UHF band (470-860 MHz).
* Some semiconductor-specific models are designed for DC to 28 MHz, with special calibration for 13.56 MHz.
* **VSWR (Voltage Standing Wave Ratio):**
* DC – 1 GHz: ≤ 1.10:1.
* 1 GHz – 2 GHz: ≤ 1.25:1.
* 2 GHz – 2.4 GHz: ≤ 1.3:1.
* Consistent, low VSWR performance across the specified frequency range is a key feature.

**Connectors:**
* **Standard Connector:** Typically features a Female LC connector.
* **Compatibility:** Fully compatible with Bird’s QC (Quick-Change) connector system for rapid replacement and reduced downtime.
* **Available Connector Types:** Various series and models are available with different connector types, including N-Type Female, LC Female, 3-1/8″ EIA Flanged, 1-5/8″ EIA Flanged, 3-1/8″ Unflanged, 1-5/8″ Unflanged, and digital options.

**Coolant:**
* **Type:** Dielectric fluid. Bird recommends using their proprietary coolant, P/N 5-1070, to prevent damage.
* **Coolant Capacities:** Available in 1-gallon and 5-gallon P/N 5-1070 (PMX-200) Silicone Oil Coolant.
* **Maintenance:** Routine checks of the load resistor and coolant levels are required for proper operation. Coolant lifetime varies based on operating temperature; for heavy use, check coolant every 500 hours.

**Environmental and Operational:**
* **Operating Temperature Range:** -40°C to 55°C. Other sources indicate -40°C to 45°C.
* **Storage Temperature:** -40°C to +45°C.
* **Orientation:** Designed for operation in a horizontal position only, with the vent plug oriented upwards.
* **Environment:** Do not use outdoors or in areas with condensing humidity. Allow at least 12 inches (30 cm) of clearance on all sides.

**Optional Features and Accessories:**
* **Thermoswitch:** Optional interlock thermoswitch (P/N 8890-008) available. This is a normally closed switch that opens at 236°C (457°F) and can be used to disable transmitter power if coolant temperature exceeds a preset limit, preventing overload damage.
* **Blower Assembly:** Models designated -315 and -320 include an integrated blower assembly for forced-air cooling, available in 115 VAC and 230 VAC configurations.
* **Connectors:** Can be equipped with various AN Standard Type connectors.

### Applications

The Bird 8890 series RF loads are utilized in a variety of applications, including:
* Testing and adjusting transmitters under non-radiating conditions.
* RF generator calibration.
* Transmitter testing and system alignment.
* System protection.
* Isolation of components under test.
* Harmonic signal analysis.
* Comparison standards.
* Labs and service applications.

### Maintenance and Safety

* **Maintenance:** Routine checks of the load resistor and coolant levels are essential. Replacement of RF input connectors can be performed by following specific procedures.
* **Safety Precautions:**
* The vent plug must be used at all times when the unit is operating or cooling. Failure to do so could result in an explosion or severe burns.
* Disconnect from all power sources before servicing.
* Do not operate with side panels removed.
* Use only Bird coolant (P/N 5-1070).
* Ensure proper AC hookup according to local electrical codes.
* Personnel performing maintenance should be qualified service personnel.
* Warning notes in the manual highlight procedures that, if not correctly performed, could result in personal injury.

Why Choose Aumictech for Bird 8890?
At Aumictech, we specialize in supplying high-performance RF test and measurement equipment. Whether you need reliable power dissipation for transmitter testing, precise signal control in laboratory environments, or robust terminations for field applications, our team ensures the Bird 8890 series delivers maximum performance and longevity for your critical applications.