Symmetricom XLi IEEE 1588 - Manual (Page 64)

56 XLi IEEE 1588 Clock
997-01510-03, Rev. C, 12/12/2006
S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S
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59 GPS antenna cable supplied with the XLi. If the GPS antenna is connected using a different antenna
length, calculate the new value using the multiple given below and adjust the value of F51. If using an
optional Down/Up Converter, consult that product’s documentation for directions on setting the correct
cable delay.
F51 Guidelines:
• For RG-59: multiply the cable length by 1.24 ns/ft. to get the value for F51.
• For RG-58: multiply the cable length by 1.4 ns/ft. to get the value for F51.
• Don’t use function F51 to adjust the XLi’s timing outputs; use F52 Distribution Cable Delay
instead.
Command Line
Use the following format to display the current Antenna Cable Delay setting:
F51B
The XLi responds using the following format:
F51Bns
where:
For example, to see the antenna cable delay for the GPS card in option bay 4, enter:
F51 B4
XLi responds:
F51 B4 +000060ns
F = ASCII character F (f or F for input string).
51 = the function number.
= ASCII space character one or more.
B = ASCII letter to denote Option Bay number follows
= Option Bay Number of the GPS option card, 1 through 4.
= carriage return character.
= one or more space characters.
= either + or blank
= 1 to 6 digit delay from 0 ns to 999999 ns.
ns = nanoseconds (ns or NS for input string).
= line feed character.