Specifications

3-30 888-2857-001 5/9/13
WARNING: Disconnect primary power prior to servicing.
Section 3 Operation
Platinum VAX-C Series
Nuisance overdrive trips can be avoided by setting the Max Crest Factor parameter
section of the RTAC Peak Reduction sub window in RTAC Setup Screen 3, on left
Figure 3-17 on page 3-27.
Nuisance overdrive trips will typically occur within 30 minutes to 1 hour after
transmitter operation with RTAC is first started. If this happens, perform the following:
STEP 1 This setup is performed with the transmitter operating at full power and
RTAC Linear and Non-Linear functions set to Adapt.
STEP 2 Start with the Max Crest Factor at the default value. See Table 3-14 on
page 27.
STEP 3 Reduce the Max Crest Factor by 0.2dB.
STEP 4 Wait for one hour to see if further overdrive trips occur. If they do,
reduce by another 0.2dB.
STEP 5 Repeat steps 3 & 4 until overdrive trips cease.
STEP 6 Excessive reduction will effect the linearity correction of the transmitter.
After Max Crest Factor has been adjusted, observe the adjacent channel
response to ensure that it still exceeds the transmitter output signal mask
requirements.
3.4.3.3 RTAC Profiles sub window
Profile Linear: For linear RTAC correction, BASIC and LONG OFFSET profiles
should be tried first. The rule of thumb here is that more is not necessarily better, so use
the first profile that works well. The equalizer length in time generally increases down
the list. Linear profile choices are:
• BASIC This correction should be used for most standard mask filters.
• SHORT
• LONG
• MAX
• BASIC OFFSET
• SHORT OFFSET
• LONG OFFSET This correction should be used for sharp tuned mask filters,
special mask filters, or when a two or more transmitters of different
frequencies are being combined into a single output through 2 or more sharp
tuned filters.