3M CTK015, Руководство пользователя

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10
You can use the Level dial to put the 3M
™
ScanEM-C Probe in squelch
mode. Follow the procedure outlined in the previous paragraph, only set the
reference level just below the point where the green LED turns on. This way
your ScanEM-C Probe will be quiet and the lights will be off until you pass it
over an area where the EM level is higher than your reference setting. When
testing a product for compliance, for example, you may want to scan some
other product that has passed the emission test before, and set the background
level of the ScanEM-C Probe to the average emission level of that product.
Then scan the product you are trying to get agency approval for in search of
spots with higher emission levels.
Setting the Level dial to zero completely disables the ScanEM-C Probe’s own
indication and is used for its operation as a probe only. Use Level settings of
one and above in stand-alone operation.
Level Dial Numbers
Î
The numbers from zero to nine on the Level dial do not refer to any specific
field strength, nor do they signify a preset spacing in field strength between any
two numbers. These numbers are put there for convenience so the user can
refer to them when recording relative field strength. You can use these numbers
to “calibrate” your ScanEM-C Probes. Once the correlation between the field
strength at the tip of the ScanEM-C Probe, the number on the dial, and the status
of the LED bar is established, it can be used for simple Go/No Go tests.
Sound On/Off
The human ear is very sensitive to pitch variation and thus can detect the
slightest change in field strength when the speaker is on.
With the Sound turned on, you can detect much finer variations in EM field
strength than by using lights as the only indicator. You may prefer to have the
sound turned off to cut down on noise, but this limits your resolution to just
five steps (five LEDs).