User Manual

RF-Orchestra!™ Transmitter Installation and Operation Maintenance
July 2000 6880493G02-C 6-21
Figure 6-4: Sample Power Supply Debug Trace Output
Check Transmitter Frequency
Transmitter Is Transmitting Far Off Frequency (More than 500 Hz)
Compare the values in the center frequency table (RFO FIPS parameters 2000-2015) to their
assigned values. If other sites are experiencing the problem, have someone verify that the
RF-C! controller has the correct frequencies in its table. Other failures such as
E_SYNTH_LOCK1_FAIL, E_SYNTH_LOCK2_FAIL, or E_PENDULUM_NOT_LOCKED, which
would cause the frequency to be off, will also prevent the transmitter from paging, thus
making the error less likely to be detected.
Transmitter Is Transmitting Slightly Off Frequency (Less Than 500 Hz)
The following paragraphs present possible causes for the transmitter being slightly off
frequency.
• Cause 1: Measurement Error
The transmitter is accurate to 2 ppb which is probably much better than the user test
instrumentation. Frequency accuracy on a spectrum analyzer is inversely proportional to
the resolution bandwidth. You can only expect 30 Hz accuracy when the RBW is set to
300 Hz. If the spectrum analyzer can accept an external reference, use a rubidium
oscillator or tap the 10MHz reference line from the BCM to the OCM. If the analyzer does
not have an external reference port, the accuracy is probably inadequate.
• Cause 2: Subchannel Table Is Incorrect
Verify the following settings for subchannel offsets (in Hz):
RFO FIPS: a 192 SHMI 1
RFO FIPS: RA 192
RFO FIPS:
<SHMI 1> PS: PS1=left: PS2=right
PS1=> 4.22 Volt(s): PS2=> 4.24 Volt(s)
<SHMI 1> PS: PS1=left: PS2=right
PS1=> 4.22 Volt(s): PS2=> 4.24 Volt(s)
<SHMI 1> PS: PS1=left: PS2=right
PS1=> 4.22 Volt(s): PS2=> 4.24 Volt(s)