The VNA Master is a field portable unit operating in the rigors of the test environment. In order to ensure measurement accuracy, RF calibration (OSLT, for example) must be performed prior to making a measurement in the field.
Anritsu recommends allowing the instrument to warm up to typical operation temperature (a minimum of 15 minutes) before calibrating. The instrument will require a new OSL calibration if the internal instrument temperature changes more than 15 ºC after calibration.
The VNA Master has no field‑adjustable components. The RF calibration components, however, are crucial to the integrity of the calibration and must be periodically verified to ensure their performance. This is especially important if the components have been dropped or over‑torqued.
Note
For best calibration results (compensation for all measurement uncertainties), ensure that the calibration is performed at the end of the test port or optional extension cable (that is, at the same point that the device that is to be tested (DUT) will be connected).
Caution
For best results, use an Anritsu phase stable Test Port Extension Cable, such as those listed in the Technical Data Sheet for your instrument (refer to Supplemental Documentation). Use of a typical laboratory cable to extend the VNA Master test port to the device under test, or any bending of the cable subsequent to the OSL or OSLT calibration, may cause uncompensated phase reflections inside the cable. Reflections of this type cause measurement errors, which are more pronounced at higher frequencies.
Annual Verification
Anritsu recommends an annual calibration and performance verification of the VNA Master and the OSL calibration components by local Anritsu service centers.
The VNA Master is self‑calibrating and has no field‑adjustable components. The OSL calibration components are crucial to the integrity of the calibration. As a result, they must be verified periodically to ensure performance conformity. This is especially important if the OSL calibration components have been accidentally dropped or over‑torqued. Contact information for Anritsu Service Centers is available at anritsu.com/contact-us.
ESD Caution
The VNA Master, like other high performance instruments, is susceptible to ESD (electrostatic discharge) damage. Coaxial cables and antennas often build up a static charge, which may damage the VNA Master input circuitry (if allowed to discharge by connecting directly to the VNA Master without previously discharging the static charge). Operators must be aware of the potential for ESD damage and take all necessary precautions.
Operators should exercise practices outlined within industry standards such as JEDEC‑625 (EIA‑625), MIL‑HDBK‑263, and MIL‑STD‑1686, which pertain to ESD and ESDS devices, equipment, and practices. Because these apply to the VNA Master, Anritsu Company recommends that any static charges that may be present be dissipated before connecting coaxial cables or antennas to the VNA Master. This may be as simple as temporarily attaching a short or load device to the cable or antenna prior to attaching to the VNA Master. Remember that the operator may also carry a static charge that can cause damage. Following the practices outlined in the above standards helps to ensure a safe environment for both personnel and equipment.
RF Input Warning (MS203xB only)
The VNA Master is a sensitive measuring instrument designed to measure low power levels. Avoid damaging this sensitive circuitry by observing the maximum input levels printed on the instrument connector labeling and specified in the product technical data sheet.
On MS203xB instrument models, typical maximum input at the spectrum analyzer port is +30 dBm (±50 VDC) and could be less if additional features, such as a preamplifier, are in use. Be sure to review the product technical data sheet or Anritsu website for recommended components and accessories that can help you protect your instrument. These include a variety of adapters, attenuators, filters, and RF detection accessories.