FF Systems FF-8070, Руководство по эксплуатации

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13
Adjustments
The FF-8070 is adjusted at the factory to balance the record level between the main and aux.
inputs. Note that the FF-8070 should not require adjustment by the user once the FF-800 and
repeater levels have been adjusted. The following procedure is for reference in the event that
adjustments become necessary.
There are two input level adjustments on the FF-8070: VR1 is the main input level, and VR2 is the aux
input level (VR3 is not installed). Refer to the parts placement diagram in appendix B for locating these
controls. The simplest means for adjusting the DVR is to use the DVR audio test function to record/play
test tracks and an oscilloscope connected to one of the FF-800 audio outputs (P4-1, 3, 5, or 7) or a service
monitor on the controller output -- if neither instrument is available, use an amplified speaker or receiver
tuned to the repeater output. While recording, monitor the signal level on the scope and compare this to
the playback level. If VR1 is properly adjusted, the playback from the DVR will have the same level as the
record operation. Repeat this process while adjusting VR1 until the record and play levels are as close as
possible.
The aux input level (VR2) is slightly more difficult to adjust since the DVR audio is redirected to the phone
during a control autopatch. Also, if a second telephone is not available at the repeater site, another person
must assist from a remote location to provide control commands and test audio over the control autopatch.
For this adjustment use an oscilloscope or an amplified speaker to monitor the DVR audio at P3-7. Adjust
VR1 First and then have the operator that will be on the control autopatch record a test message in one of
the system tracks (use the main input for this track). When the operator establishes the control autopatch
connection, they must issue the Input Source Set command to switch the DVR to the aux input (<spi6
#22>). The operator on the control autopatch will alternately perform an Audio Test and Play system
track of the test track recorded earlier. By comparing the track recorded from the "main" input with the
test track from the "aux" input, the person at the repeater site can adjust VR2 to balance the two inputs.
The operator on the control patch must continuously rerecord the Audio Test track so that the new input
level can be compared to the main input level (via the Play system track command). Also, note that the
aux audio is affected by digital POT#6 on the FF-800, and therefore this adjustment should be completed
prior to adjusting VR2 on the DVR.