Spectracom VelaSync 1225, User Manual

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3. Locate the Offset field, and enter the desired value.
4. Click Submit.
Calculating cable delay
The following formula can be used to calculate antenna cable delay:
D = ( L * C ) / V
Where:
D = Cable delay in nanoseconds
L = Cable length in feet
C = Constant derived from velocity of light: 1.016
V = Nominal velocity of propagation expressed as decimal, i.e. %66 = 0.66 Value is provided
by cable manufacturer.
When using Spectracom LMR-400 or equivalent coaxial cable, this formula equates to
approximately 1.2 nanoseconds of delay per every foot of cable. To calculate the Offset
value (cable delay), multiply the length of the entire cable run by “1.2” and then enter
this value into the Offset field.
E x a m p l e s o f L M R - 4 0 0 ( o r e q u i v a l e n t ) c o a x
c a b l e d e l a y s :
100 feet of cable = 120 nanoseconds of cable delay
200 feet of cable = 240 nanoseconds of cable delay
300 feet of cable = 360 nanoseconds of cable delay
3.3.3.7 Resetting the GNSS Receiver
The Reset Receiver command causes the GNSS receiver to execute a cold start: All
data will be erased from the volatile receiver memory. Only non-volatile memory is
3.3 Managing References
CHAPTER
3
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