User`s guide

Si47xx-EVB
44 Rev. 0.8
11
RDS Deviation. Enter the desired RDS deviation in this window (Si4711/13/21 only).
0–7.5 kHz
12
Total Deviation. This is an indicator only displaying the sum of the audio, pilot and RDS
deviation. If the total deviation exceeds 75 kHz, the indicator will turn red and a warning
sign is displayed.
0–187.5 kHz
13
Input Mute Left/Right. Selecting this checkbox will mute the Left or Right audio channel.
On/Off
14
Turn on or off the pilot tone for stereo or mono FM transmit mode.
On/Off
15
Turn on or off the RDS transmission (Si4711/13/21 only).
On/Off
16
Modulation On. Selecting this checkbox will modulate the audio, pilot, and RDS signal
according to the audio, pilot, and RDS deviation. De-selecting this checkbox will turn off
modulation for all audio, pilot, and RDS signal and only the carrier will be transmitted.
On/Off
17
Turn on or off the L-R channel for stereo or mono FM transmit mode.
On/Off
18
Turn on or off the compressor for the audio signal.
On/Off
19
Attack time. Set the attack time for the compressor in milliseconds.
0.5–5 ms
20
Release time. Set the release time for the compressor in milliseconds.
100–1000 ms
21
Threshold. Set the threshold for the compressor.
–40 to 0 dBFS
22
Input Gain. Set the compressor gain.
0 to 20 dB
23
Limiter Release Time. Set the limiter release time constant.
(Not available in Si4710-A10).
0.5,1,2,3,4,5,6,7,8,
9,10,20,30,40,50,
75,100 ms
24
Turn on or off the limiter feature.
On/Off
25
Audio Level Indicators. Overmodulation, Limiter, Audio input level below low-level
threshold (silence detection), and Audio input level below high-level threshold (loud
detection). To enable these four indicators, check the Enable Interrupts box. These
indicators are sticky; to clear them, click the Reset button.
26
Mode switch buttons to switch between different modes on the device. See section 4 for
more information.
Table 8. FM Transmitter Main Window Descriptions (Continued)
# Description Range