User's Manual

PTP 250 User Guide Compliance with radio regulations
phn-2182_002v000
May 2011
4-31
Calculating RF cable loss (FCC only)
The FCC approval for the product is based on tests with a cable loss between the ODU
and antenna of not less than 1.2 dB at 5.8 GHz. If cable loss was below 1.2 dB, the
connectorized PTP 250 would exceed the maximum EIRP allowed under FCC 5.8 GHz
rules.
Cable loss depends mainly upon cable type and length. To meet or exceed the
minimum loss of 1.2 dB, use cables of the type and length specified in Table 4-22
(sour
ce: Times Microwave). This data excludes connector losses.
Table 4-22 RF cable lengths required to achieve 1.2 dB loss at 5.8 GHz
RF cable type Minimum cable length
LMR100 0.6 m (1.9 ft)
LMR200 1.4 m (4.6 ft)
LMR300 2.2 m (7.3 ft)
LMR400 3.4 m (11.1 ft)
LMR600 5.0 m (16.5 ft)