Spectracom Corporation
8194B, 8195B, 8197B
GPS Ageless Master Oscillator Instruction Manual
4-25
The frequency offset at the carrier frequency is determined by the formula:
Δ
fc = Fc x
Δ
fs
Where:
Δ
fc = carrier offset
Fc = carrier frequency
Δ
fs = offset of 10 MHz standard (from the tables)
To read the 10 MHz offset value issue the
1FO
command as shown below:
Type:
1FO <ent>
Response: 10MHZ OFFSET = NONE
To select a 10 MHz simulcast offset, place the unit in Set mode and issue the 1FO
command as follows:
Type:
1FO SCn so<ent>
Where:
n = Simulcast Offset Group: 1 or 2.
s = Sign, positive or negative: + or -.
o = Offset #: 1,2,3 or 4.
To remove a 10 MHz simulcast offset and return the unit to no offset operation, place
the unit in Set mode and issue the 1FO command as follows:
Type:
1FO 0<ent>
Examples:
Configure the Master Oscillator 10 MHz outputs for a VHF 150 MHz simulcast offset of
–7 Hz. From Table 4-4 this offset value is equivalent to SC2 –3.
To enter in the 10 MHz offset value place the unit in Set Mode to allow configuration
changes then issue the 1FO command as shown below:
Type:
SM ON <ent>
Response:
SET MODE ON
Type:
1FO SC2 -3 <ent>
Response:
The unit responds with a message stating that Phase Lock
Process has been halted and a frequency offset has been specified.
