Setting the P25 Decode Level for the BCD396XT and BCD996XT and other tips

Digital Decode Threshold

P25 LP Filter 
This setting lets you set the scanner to apply a software filter that removes the 4kHz tone you can hear on some P25 systems. Note that turning on this setting increases the CPU load and could slightly degrade P25 decode performance on some systems. 
P25 Waiting Time (BCD396XT and BCD996XT Only) 
On channels that contain a mix of analog and digital signals (i.e., where the Audio Mode is set to All), it is possible to have false decode problems caused by digital noise at the beginning of transmissions. To prevent this, a user-configurable P25 wait time (from 0 to 1000 ms) has been added. 
During the wait time, the scanner evaluates the received signal; if it detects P25 data, the scanner opens squelch immediately. If it does not detect any P25 data, the scanner opens squelch as soon as the wait time expires. 
Note: Any analog transmissions on this channel will lose the first part of the transmission, up to the wait time you set here. Select the number of milliseconds (after the start of a transmission) the scanner should wait while checking for P25 data. Choose a number from 0 through 1000 ms in 100 ms increments. The scanner only applies the wait time setting to Conventional or Motorola (non P25) systems, and only when the channel's Audio Mode setting is All

P-25 adjustment level settings If you press and hold the "hold" button and turn on the scanner the screen will flash colors and allow you to get into the P25 settings. Then press menu and go to settings and then go to P25 adjust level. You will notice it is set to 50 for the default auto setting. If you change it to 200 (press 200 enter) now the default level will always be 8 and if you change it to 100 the default will be set to 11. You can check this when scanning by pressing Func then volume, Func then volume to watch the threshold. Auto works well for me but setting it to 200 isn't bad because most of the digital systems level off around 8 using the auto setting anyway. If you find that the default setting works best just set it back to 50 by pressing 050 enter
P25 Adjust level 50 ( I have mine set at 85. The lower this setting is the faster it tries to correct the audio but this can cause the decode audio to sound a little fluttery. The higher the number, the slower it samples the signal but can give you better decode on some systems. )  

Setting the P25 Decode Level for the BCD396XT and BCD996XT and other tips 
You can still view the decode screen but that is all you can do 
To view the decode screen with the 996XT, press the scroll control then Vol.
To view the decode screen with the 396XT, press Func then Vol while you are viewing the volume adjust or squelch adjust screen. 
The adjustments require a different method. There is also no need to to be in HOLD mode or be monitoring a single system. Probably the closest equivalent to 'Analyze' mode in the RS/GRE digital scanners.
1. Hold the HOLD key while powering up the scanner. The screen will flash all of the colors twice 
2. Press Menu; go to Settings
3. Three options (2 new) will appear; 
1. P25 LP Filter
2. P25 Adjust Mode (new) 
3. P25 Adjust Level (new) 
• P25 LP Filter - lets you set the scanner to apply a software filter that removes the 4kHz tone you can hear on some P25 systems. Note that turning on this setting increases the CPU load and could slightly degrade P25 decode performance on some systems. The option is on or off. 
• P25 Adjust Mode - This mode sets the algorithm for P25 decode. Leave it at 3. Anything higher than 3 will just act like 3. Anything lower will have the reduced performance of previous firmware versions on the 396T. 
• P25 Adjust Level - sets the RSSI value below which the scanner will not attempt to make P25 fine tune adjustments. If the signal is too low, RX reliability is not high enough to make P25 adjustments correctly. 50 is the default setting (1-200). People have had better decoding with this value turned up. 
• P25 Waiting Time - (In the Conventional systems and Motorola site menus) On channels that contain a mix of analog and digital signals (i.e., where the Audio Mode is set to All), it is possible to have false decode problems caused by digital noise at the beginning of transmissions. To prevent this, a user-configurable P25 wait time (default 400ms; 0 to 1000 ms) has been added. During the wait time, the scanner evaluates the received signal; if it detects P25 data, the scanner opens squelch immediately. If it does not detect any P25 data, the scanner opens squelch as soon as the wait time expires. 
Note: Any analog transmissions on this channel will lose the first part of the transmission, up to the wait time you set here. Select the number of milliseconds (after the start of a transmission) the scanner should wait while checking for P25 data. Choose a number from 0 through 1000 ms in 100 ms increments. The scanner only applies the wait time setting to Conventional or Motorola (non P25) systems, and only when the channel's Audio Mode setting is All.

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