LMR Master preventive maintenance consists of cleaning the unit and inspecting and cleaning the RF connectors on the instrument and on all accessories. Clean the LMR Master with a soft, lint‑free cloth dampened with water or with water and a mild cleaning solution.
Caution
To avoid damaging the display or case, do not use solvents or abrasive cleaners.
Connector Care
Clean the RF connectors and center pins with a cotton swab dampened with denatured alcohol. Visually inspect the connectors. The fingers of the N(f) connectors and the pins of the N(m) connectors should be unbroken and uniform in appearance. If you are unsure whether the connectors are undamaged, gauge the connectors to confirm that the dimensions are correct. Visually inspect the test port cable(s). The test port cable should be uniform in appearance, and not stretched, kinked, dented, or broken.
To prevent damage to your instrument, do not use pliers or a plain wrench to tighten the Type‑N connectors. The recommended torque is 12 lbf · in to 15 lbf · in (1.36 N · m to 1.70 N · m). Inadequate torque settings can affect measurement accuracy. Over-tightening connectors can damage the cable, the connector, the instrument, or all of these items.
Visually inspect connectors for general wear, cleanliness, and for damage such as bent pins or connector rings. Repair or replace damaged connectors immediately. Dirty connectors can limit the accuracy of your measurements. Damaged connectors can harm the instrument. Connection of cables carrying an electrostatic potential, excess power, or excess voltage can damage the connector, the instrument, or both.
Connecting Procedure
1. Carefully align the connectors. The male connector center pin must slip concentrically into the contact fingers of the female connector.
2. Push connectors straight together. Do not twist or screw them together. A slight resistance can usually be felt as the center conductors mate.
3. To tighten, turn the connector nut, not the connector body. Major damage can occur to the center conductor and to the outer conductor if the connector body is twisted.
4. If you use a torque wrench, initially tighten by hand so that approximately 1/8 turn or 45 degrees of rotation remains for the final tightening with the torque wrench.
Relieve any side pressure on the connection (such as from long or heavy cables) in order to assure consistent torque. Use an open‑end wrench to keep the connector body from turning while tightening with the torque wrench.
Do not over-torque the connector.
Disconnecting Procedure
1. If a wrench is needed, use an open‑end wrench to keep the connector body from turning while loosening with a second wrench.
2. Complete the disconnection by hand, turning only the connector nut.
3. Pull the connectors straight apart without twisting or bending.
ESD Caution
The LMR Master, like other high performance instruments, is susceptible to ESD damage. Coaxial cables and antennas can easily build up a static charge, which (if allowed to discharge by connecting directly to the LMR Master without first discharging the static charge) may damage the instrument input circuitry. Operators must be aware of the potential for ESD damage and must 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 standards apply to the LMR Master, Anritsu Company recommends that any static charges that may be present be dissipated before connecting coaxial cables or antennas to the LMR Master. This may be as simple as temporarily attaching a short or load device to the cable or antenna prior to attaching to the LMR Master. Remember that the operator may also carry a static charge that can cause damage. Following the practices outlined in these standards helps to ensure that a safe environment exists for both personnel and equipment.