TCG 01 User Manual
9
th
Edition: February 2007
Page 25 of 49
Appendix A
A
NTENNA
D
ETAILS
A.1
Antenna Cable Specification
The TCG 01 is supplied with 15, 30, or 60 metres of high performance RF cable factory-
fitted with a TNC-type male connector at one end, and a SMA male connector at the
other. The TNC-type connector mates with the connector on the antenna and provides a
robust and weather-resistant connection. The smaller SMA connector mates with the
connector on the TCG 01 rear panel and is only fractionally larger in diameter than the
cable itself; this facilitates installation in conduit and through small apertures. The
supplied cable has the following characteristics:
Centre conductor:
1.42mm dia Solid bare copper
Dielectric:
3.81mm dia Low loss, closed polyethylene foam (Cellular PE)
Shield:
3.94mm diameter Aluminium Laminated Tape bonded to the
Dielectric, with a Tinned Copper Overbraid – 4.52mm diameter
Jacket:
6.10mm Black Polyethylene
Bending Radius:
40mm (maintaining less
WKDQ
impedance change at bend).
Weight:
0.051 kg/metre
Temperature Range:
-40
o
C to +85
o
C
Impedance:
50
Velocity:
84%
Capacitance
79.4pf/metre
Centre
conductor
10.5
per 1000 metre
DC
Resistance
Shield:
2.8
per 1000 metre
Attenuation:
0.33dB per metre @ 1575.42MHz (L1)
Shielding:
> 90dB
Phase Stability:
+/- 10ppm/degree C
Care should be taken during installation to ensure that the minimum bending radius
limit noted above is scrupulously maintained.
While the cable shielding is excellent, the cable should not be routed in close
proximity to power cables or other RF cables carrying transmitter signals – in
particular, parallel runs are to be avoided if possible. If such runs are absolutely
unavoidable, a minimum separation of 30cm may be used as a guideline.
The GPS receiver embedded in TCG 01 has excellent OOB rejection characteristics, as
does the antenna itself. However, sound engineering practice should not rely on these
factors alone to guarantee performance. Careful installation will enhance the long-term
reliability and on-going stability of the Time Code Generator.
