The Keysight (Agilent/HP) 8485A is a thermocouple-based RF and microwave power sensor designed for accurate average power measurements. It covers a frequency range of 50 MHz to 26.5 GHz and measures power levels from -30 dBm to +20 dBm (1 µW to 100 mW). The sensor provides a 50-ohm input via a 3.5 mm male connector and features excellent SWR performance to minimize mismatch uncertainty.
Specifications
Physical
| Parameter | Value |
|---|---|
| Operating Temperature | 0 to 55 °C |
| Weight | 0.18 kg |
Basic Specifications
| Parameter | Value |
|---|---|
| Sensor Type | Thermocouple |
| Measurement Type | Average Power |
| Frequency Range | 50 MHz to 26.5 GHz |
| Power Range | -30 dBm to +20 dBm (1 µW to 100 mW) |
| Dynamic Range | 50 dB |
| Nominal Impedance | 50 Ω |
Maximum Input Limits
| Parameter | Value |
|---|---|
| Maximum Average Power | 300 mW |
| Maximum Peak Power | 15 W |
Interfaces and Connectivity
| Parameter | Value |
|---|---|
| RF Input Connector Type | 3.5 mm |
| Connector Gender | Male |
Compatibility and Storage
| Parameter | Value |
|---|---|
| Compatible Power Meters | EPM, EPM-P, P-series, E1416A VXI, 70100A, 43X series |
Performance
| Parameter | Value |
|---|---|
| Maximum SWR (50 MHz to 2 GHz) | 1.15 |
| Maximum SWR (2 GHz to 12.4 GHz) | 1.19 |
| Maximum SWR (12.4 GHz to 18 GHz) | 1.25 |
| Maximum SWR (18 GHz to 26.5 GHz) | 1.29 |
| Zero Set | ±50 nW |
| Zero Drift | ±15 nW |
| Measurement Noise | 110 nW |
Environmental
| Parameter | Value |
|---|---|
| Storage Temperature | -40 °C to +75 °C |
| Operating Humidity | < 95% at 40 °C (non-condensing) |
Calibration
| Parameter | Value |
|---|---|
| Calibration Reference Frequency | 50 MHz |
| Calibration Reference Power | 1 mW (0 dBm) |
| Calibration Data | Calibration factor table printed on sensor body |
Power
| Parameter | Value |
|---|---|
| Power Requirements | Powered by host power meter (via Keysight/HP 11730A-series cable) |
Technology
Thermocouple
Applications
RF and Microwave Power Measurement