4-2
Document number: S46-901-01 Rev. F / March 2011
Section 4: Service Information
S46/S46T/S46L Microwave Switch System Instruction Manual
Coaxial switch performance verification
The following paragraphs discuss a channel resistance verification procedure.
CAUTION
Contamination will degrade the performance of the S46/S46T/S46L. To
avoid contamination, do not touch the connector mating surfaces.
As is the case with any high-resistance device, the integrity of connectors can be damaged if they
are not handled properly. If connector insulation becomes contaminated, the insulation resistance
will be substantially reduced, affecting RF paths.
Oils and salts from the skin can contaminate connector insulators, reducing their resistance. Also,
contaminants present in the air can be deposited on the insulator surface. To avoid these
problems, never touch the connector insulating material. In addition, use the switch only in clean,
dry environments to avoid contamination.
If the connector insulators become contaminated, either by inadvertent touching or from airborne
deposits, clean with a cotton swab dipped in clean methanol.
NOTE
Failure of any performance verification test may indicate that the instrument is
contaminated. See
Handling and cleaning precautions
earlier in this section for
information on cleaning the controller.
Environmental conditions
All verification measurements should be made at an ambient temperature between 18° C and
28° C, and at a relative humidity of less than 70 percent.
Recommended equipment
summarizes the equipment necessary for performance verification (channel resistance
tests). Required cables and multimeter may be purchased from Keithley Instruments.
Channel resistance tests
Perform the following steps to verify the switch contact is closing properly, the switch resistance is
within specification, and that the switch opens properly.
1.
Turn on the Model 2010 digital multimeter (DMM) and allow it to warm up for one hour
before making measurements.
Table 4-15
Recommended verification equipment
Manufacturer/Model
Equipment description (Qty) Specifications
Keithley Model 2010
Digital multimeter (1)
10
Ω
range, 60 ppm
Keithley S40-0217
SMA F/F adapter (1)
Keithley S40-0218
BNC/F to single banana plug (2)
adapter
Keithley S40-0219
BNC/M to SMA/M cable (2)
0.609 m (24 in.) long
