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loop design or more powerful driver is required. This is potentially
due to metal loss.
5. Briefly alter the current to the desired level. For instance, the
example in step 4 requires 4 amps of current.
6. The field strength will now be 0dB +/- 1dB.
7.
Quickly record the current required to achieve 0dB field
strength. Now switch the TSG to 1.6kHz.
8. Confirm that the Loop A and Loop B Clip LEDs remain unlit.
10. If the driver’s front panel Clip LEDs remain unlit, return the TSG to
1kHz and reduce output current to 2 amps move on to Step 4: Field
Uniformity.
If the driver’s front panel Clip LEDs are lit, the driver is clipping.
This means the loop connected is too long, and therefore:
1. The system is not IEC60118-4 compliant.
2. The sound will be distorted.
3. The driver may be susceptible to damage and warranty voided.
Perform one of the following solutions and repeat until there is no
clipping:
1. Reduce the loop current,
2. Reduce the length of the loop,
3. Use a higher diameter of flat cable,
4. Try a two-turn loop,
5. Use a higher voltage driver.
Step 4: Field Uniformity
1.
Set up the FSM. Ensure that the two vertical arrows in the top-right
corner of the FSM are placed at the correct height:
•
3’ 9” for seated user.
•
5’ 6” for standing users.
A
tripod or similar for mounting the FSM is recommended.
