Keysight 478A-H13 – Option for 478A; 100KHz to 1GHz, Max SWR 1.8 to 300KHz, 1.3 to 1GHz, Std Lab Cal at 13 Frequencies

The 478A Option H13 is a standard 478A Coaxial Thermistor Mount that has been modified to operate from 100 kHz to 1 GHz. The unit, selected from a small batch of units (current production) for the best available VSWR, is then sent to the Keysight Standards Lab for calibration at the following frequencies: 100, 300, and 500 kHz; and 1, 3, 5, 10, 30, 50, 100, 300, 500, and 1000 MHz.

The calibration is ISO compliant but does not include the17025 accredited calibration. The calibration report will include Cal Factor and RHO data with uncertainties. The lower frequency is accomplished by the design of the RF input connector (00478-62004) and thermistor assembly (00478-62005), which utilizes a 0.1 µF capacitor for C1 and C2.

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