Specifications

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WARNING: Disconnect primary power prior to servicing.
Section 3 Operation
Platinum VAX-C Series
Dynamic Delay Select Off (MFN) (Multi Frequency Network) or On (SFN) (Single
Frequency Network).
- MFN mode selects operation in a Multiple Frequency Network
(transmitters on different frequencies) which does not require
synchronization with the other transmitters in a network.
- SFN mode selects operation in Single Frequency Network (transmitters
on same frequency) which requires synchronization with other
transmitters in a network.
- If SFN is selected a GPS antenna is utilized. The PFRU set up specifies
Internal GPS. See Section 3.4.5 on page 3-33. 1PPS may also be used
for SFN synchronization in some applications. This applies to every
modulation mode that supports SFN.
Output Process Time Enter a value in microseconds (S). Time settings are used to synchronize
the transmission timing for single frequency networks. Output process
time is the additional time delay of equipment after the LPU in the RF
transmission path. It controls setting of RF and antenna delay. Non
volatile setting of 0-100S causes exciter output to be emitted sooner.
This additional delay is needed so that the transit time (through the
transmitter power amplifier, high power filter, and transmission line) can
be included in the LPU delay.
Adjust ETI Static
Delay
Enter a value in milliseconds (mS). ETI static delay is additional time
entered to delay LPU emission in MFN mode. In static delay mode this
non-volatile setting controls the overall exciter signal delay. Range T
min
to 999.9999 mS. T
min
varies by DAB mode and can be seen by entering 0.
In dynamic delay mode this non-volatile setting provides local offset
delay. Range is T
min
to 999.9999mS.
Static Delay
Compensation
Amount of delay above the minimum required to meet the Adjust Static
Delay time.
ETI 1 Dynamic
Comp
Adjustable signal delay used to balance out the different transit times of
the transmitters in a single frequency network (compensation delay), plus
and individual delay to optimize SFN signal coverage (offset delay) when
necessary.
ETI 2 Dynamic
Comp
See above.
Overall Transit Time The signal processing time (static delay), the compensation delay, and the
offset delay are added together, and the total is displayed here. Output
process time does not affect overall transit time since this is more of a calibration
factor for the system from the exciter output thru the antenna.
Table 3-50 Xmtr Home>Exciter Home>Setup>DAB Modulator & >Next
Field Explanation