The coordinates of the beacon are: Latitude: 37.14°, Longitude: -121.96°.
The maximum signal power of this beacon was noted to be 15 W. The minimum received signal level at 7.5 GHz is approximately -90 dBm (1 mW), with an Antenna Height of 5 m.
Transponder and beacon security
The security of the signal is weak due to the co-existence of commercial and private wireless LANs (i.e. 802.11b, g and n), low cost devices such as unlicensed Digital Video Broadcasting receivers and simple software solutions.
Explanation of DTV and TV for hearing impaired users
During normal speech, the speech information is superimposed over the desired (i.e. TV) signal by the DTV system. This information in the desired signal contains the location of the listener (e.g. which channel and which program), and is superimposed by the DTV system. This "superimposed" data on the desired signal is the TV for a hearing impaired user.
If the TV signal is lost or unclear, or if the DTV system does not work properly, the hearing impaired user is unable to receive the TV signal as intended, and may instead receive or be confused by other TV signals.
For example, in a typical home with a TV in the living room, the hearing impaired user may, in addition to the signal intended for the TV, also receive channels from the wireless LAN, or from microwave (MVTV) broadcasts, and/or telephone signals, and/or various other radio, TV, and wireless signals from the home or neighboring homes, or from other houses, streets, or buildings.
Using the TV for hearing impaired users does not interfere with the communication of other wireless users, as the TV signal is restricted to its specified frequency band (e.g. 6 MHz). Since the desired TV signal is not degraded by being superimposed upon the DTV signal, the television for hearing impaired users can still be used even when the audio is only available in a degraded form as a result of the TV being close to the DTV.
TV for hearing impaired users in the US
In the US, the hearing impaired can make their own TV for themselves by using an unlicensed TV set. There are two options, depending on which makes the most sense.
The first option is to purchase an unlicensed TV set
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