frequency 108MHZ, then open the key to confirm and enter the low-end
76MHZ, set to open key and then press to confirm, the screen display OFF,
that setup is complete, the normal work.
Notes :76-82Mhz frequency range of power is not flat, the sound quality is
not good at frequencies above 83-108Mhz; Don’t alter the transmitter highest
and lowest 76 MHz 108 MHz , even if you set up to 200 MHz is also not work.
FM transmitter for transmitting distance instructions
FM transmitter range related to a lot of conditions and factors:
First, the FM transmitter antenna be used:
FM transmitter antenna simple divided into "the class" "GP class" "indoor use with
a small class", and to get to the launch of the far distance, shall adopt the "car" and
"GP" antenna, which depends on your purpose and decide, GP antenna looks like a
umbrella of stents, his launch distance is the most ideal; The second is "car"
antenna; And the "rubber" and "bars" such as small antenna is indoor use, empty
areas farthest distance launch only 300 meters.
Second, the FM transmitter power
The launch of the transmitter of power and cover is proportional to the area. Round
area formula: S = π times round the square of r; formula: S = 2 * 3.14 r2; R says
this round radius, can see, radius r into of the original 2 times, the area into the
original 4 times. So, the push to come over, transmitter power increase 4 times,
four times the area covered also increases, so, the launch radius r will turn into the
original 2 times, so, draw the conclusion, launch power increase for the original
four times, distance to launch a doubled. Of course, this is calculated value ideal, in
fact, want to double the size of the launch distance, the transmit power to increase
more than four times, sometimes may be up to 10 times.
Third, the FM transmitter use of the environment
To 5-watt machine, for example, 5-watt FM transmitter using GP antenna and
the antenna mounted on the building's highest point, if there are no obstacles
around the case to launch four kilometers away, but if you use in buildings,
may also only 1 km from the transmitter, another example of your buildings