Toa IR-702T - Manual (Page 26)

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[Example 2]
When connecting 4 infrared wireless receivers to a single tuner using a single coaxial cable
Precondition: Cable distance (L2) from the distributor to the receiver is assumed to be 25 m (27.34 yd).
Assuming that the RG-59/U coaxial cable is used in wiring between the distributor and the receiver, the
attenuation of this distance is:
Attenuation = 3.3 dB x (25 m / 100 m) = 0.825 dB.
Since loss of 8.5 dB results from the distributor, the maximum permissible loss from the infrared wireless tuner
to the distributor stands at 2.675 dB (12 dB – 0.825 dB – 8.5 dB).
If the RG-6/U coaxial cable is used in wiring from the tuner to the distributor, given the wiring distance
between the two is L1,
L1 = (coaxial cable attenuation/coaxial cable attenuation per 100 m)
= (2.5 dB / 2.7 dB) x 100 m
= 92 m (100.61 yd)
Maximum cable length (wiring distance from the infrared wireless tuner to the infrared wireless receiver) can
be found from the following equation:
L = L1 + 25 m
= 92 m + 25 m
= 117 m (127.95 yd)
Similarly, the maximum cable length (wiring distance from the tuner to the receiver) calculated relative to the
type of coaxial cable used between the tuner and the distributor is as shown in the table below:
Infrared wireless tuner Infrared wireless receiver Distributor
L
L1 25 m or 27.34 yd (L2)
RG-59/U 348 m (380.58 yd)
RG-6/U 414 m (452.76 yd)
RG-11/U 542 m (592.74 yd)