DTC Communications VXS250 Appemdix A manual

Appendix A: Using Antennas with the VBS/VBL-250 Video Transmitter

Minimum Spacing (inches)

Bodyworn applications:

When the VBS/VBL-250 video transmitter is to be worn on the body, only the
DTC VidiWire antenna system should be used. This antenna has been extensively tested
and found to be safe when used as directed. The antennas used in the VidiWire system
are clearly labeled as to which side of the antenna should be placed against the body.
These directions must be observed to insure safe and effective operation.

Non-portable applications:

In fixed location applications any suitable antenna may be used. However, to
insure safe operation, it is imperative that proper spacing be maintained between the
radiating surface of the antenna and any persons body. The required spacing depends on
the RF output power of the transmitter and the gain of the antenna being used. The chart
below shows the correct minimum spacing for antennas used with the VBS/VBL-250
transmitters. If the gain of the antenna is unknown, contact the manufacturer of the
antenna for this information. To insure that proper spacing is maintained, locate the
transmitter or arrange physical barriers in such away that people are prevented from
approaching too closely.

Minimum Allowable Spacing Between the Antenna and the Human Body

(VBS/VBL-250 Video Transmitter)

40

35

30

25

20

15

10

5

0

0 5 10 15 20 25

Antenna Gain (dB)