Pacific Research Solutions RI-300e User Manual
Page 78
S-Cmd 52 DETAIL SQUELCH SET UP
The squelch system on the RI-300 can be fine-tuned for a given application. The following items may be changed to achieve a
different result in your application. The best way to learn more about these adjustments is to experiment with them. Notice that
each adjustment will have its own range.
Upper Threshold: The upper squelch threshold value is compared to the squelch A/D converter value to determine
when to close the squelch. Do not set upper threshold less than lower threshold.
Lower Threshold: The lower threshold value is compared to the squelch A/D converter value to determine when to
open the squelch. Do not set lower threshold more than upper threshold.
Acquisition Time: The SmartSquelch acquisition time is in 10 ms increments. This is the time that the squelch
noise must be below the lower threshold in order to activate the COS.
Delay Factor: This delay is is used by SmartSquelch to keep the squelch open for a weak or choppy signal.
The delay factor is the maximum time in 10 ms increments that the squelch will remain open.
Average Factor: The average factor is used by SmartSquelch to determine how long of a period in 10 ms
increments that noise history is used for processing.
Weak Signal Threshold: The SmartSquelch Weak Signal Message is triggered based on an evaluation of its noise history.
The weaker a signal is, the longer a squelch delay will occur. The length of this time delay can
be used to trigger the “weak signal” courtesy message.
SYNTAX: 52 [Item] [Value]
READ BACK 52 [Item]
STORAGE: RAM/EEPROM
RANGE: Item 1 = Upper threshold, Value range = 75 – 200
Item 2 = Lower threshold, Value range = 50 – 150
Item 3 = Acquisition time, Value range = 0 – 50 in 10 ms increments
Item 4 = Delay factor, Value range = 0 – 255
Item 5 = Average factor, Value range = 0 – 50
Item 6 = Weak signal threshold, Value range = 3 to 50 in 10 ms increments
PARAMETERS: Item 1 through 6, Value as listed in range.
DEFAULT: Item 1 Upper threshold = 160
Item 2 Lower threshold = 130
Item 3 Acquisition time = 8 (80 ms)
Item 4 Delay factor = 125
Item 5 Average factor = 25
Item 6 Weak signal threshold = 5 (50 ms)
EXAMPLE: 52 1 200 Sets new squelch upper threshold value to 200
52 2 90 Sets new squelch lower threshold value to 90