53
Making and Checking RF Settings (UHF)
sign
level
asing
ntly,
a 5
nce
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ease,
ecause
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of the
e TX
m of the
e third-
Using settings established as acceptable in steps 1 – 4, power up all transmitters and check the service area
for the desired channel. If the service area for the desired channel is achieved, the service area for other
channels should also be equal or better. By checking the service area with multiple sets of parameters, the
degree of leeway can be established. You should then select the optimal parameters for operation.
Step 5 Checking Simultaneous Multi-channel Operation
For example, with a result such as shown above, settings 3, 4, and 5 will produce a Zone B type service area
which meets the requirements. Either of these settings can be chosen. However, with setting 4 the RF level
margin is smaller than with setting 5. Taking the possible influence of the body effect into consideration,
settings 3 or 5 therefore are a better choice for stable operation.
With setting 3, the transmitter output is 1 mW. Compared to the 10 mW of setting 5, battery life will be
extended by about 10 to 20 percent.
With setting 5, the transmitter output is 10 mW. Compared to the 1 mW of setting 3, the higher RF level is
more suitable for situations with a lot of movement.
It is also possible to use setting 3 as a general system setting, and increase the RF level to 10 mW only in one
or more specific channels with lots of movement, to enlarge the service area for these channels. However,
because third-order intermodulation distortion will increase in this case, and channels that may be affected
should be checked beforehand. For safety, operation in all channels should be checked before going into
operation.
16 Power up all transmitters. Establish a setup simulating the expected conditions during actual
operation, and have a person with the TX stand in a position closest to the antennas.
Example: If the TX is the DWM-01, it should be held in the hand, close to the mouth.
If the TX is the DWT-B01, it should be worn on the hip, and the person should stand at the rim of the
stage, approaching the antenna.
17 Move the desired channel TX throughout the service area and check at various locations.
Setting example for checking
Band to use: Band established in step 1.
Group to use: Group established in step 1.
Antenna installation location/orientation: As determined in step 2
Antenna gain: As determined in step 2.
Number of antennas: As determined in step 2.
TX RF power: Setting that cleared the requirements of steps 3 and 4.
RX attenuator: Setting that cleared the requirements of steps 3 and 4.
Operation Check
Check the following:
No dropouts in audio signal
At least 2 segments of RF indicator shown throughout
RF indicator lit in green
QL meter shows more than 4 segments
18 Check the service area with multiple combinations of TX RF power and RX attenuator
settings.
Then select the combination that best matches the anticipated operation conditions.
Procedure
Sample results
TX RF power
1 mW
10 mW
Step 3
Step 4
Step 5
Step 3
Step 4
Step 5
RX ATT
10 dB
Setting 1: Zone A
Setting 4: Zone B
Poor
(Good)
(Poor)
Good
Good
Good
5 dB
Setting 2: Zone A
Setting 5: Zone C
Fair
(Good)
(Fair)
Good
Good
Good
0 dB
Setting 3: Zone B
Setting 6: Zone C
Good
Good
Good
Good
Fair
(Fair)
Configuring a DWX System
