Keysight 478A-H63 - Option for 478A; 100kHz to 1GHz, Max SWR 1.8 to 300kHz, 1.3 to 1GHz
The 478A Option H63 Coaxial Thermistor Mount is similar to the standard 478A with one exception. It is designed to measure microwave power from 1 μW to 10 mW over a frequency range of 100 kHz to 1 GHz.
The lower frequency is accomplished by the design of the RF input connector (00478-62004) and thermistor assembly (00478-62005) that utilize a 0.1 μF capacitor for reference designators C1 and C2.
478A options
Keysight offers several options for the 478A, as can be seen below. Please note, the 478A is sold separately.
478A-H55 - 1MHz to 1GHz, max SWR 1.3
478A-H63 - 100kHz to 1GHz, max SWR 1.8 to 300kHz, 1.3 to 1GHz
478A-H72 - 1MHz to 1GHz, max SWR 1.2
478A-H73 - 1MHz to 100MHz, max SWR 1.1 except 1.05 at 50MHz
478A-H75 - 1MHz to 1GHz, max SWR 1.3 except 1.05 at 50MHz
478A-H76 - 1MHz to 1GHz, max SWR 1.3 except 1.05 at 50MHz. Std lab cal at 50MHz
478A-H83 - 1MHz to 1GHz, SWR 1.05 at 50MHz. Std lab cal 1, 3, 10, 30, 50, 100, 300, 1000 MHz
478A-H93 - 1MHz to 1GHz, max SWR 1.3 except 1.05 at 50MHz. Std lab cal at 50MHz and 100MHz
478A-H13 - 100KHz to 1GHz, max SWR 1.8 to 300KHz, 1.3 to 1GHz, std lab cal at 13 frequencies