Generally, "delay" is the time the radio stays on a channel or talkgroup following a transmission (awaiting a potential response).
Hold is a timer that is applied to how long the radio stays on a trunk system control channel before moving on to the next system or channel. The intent of the default of HOLD=0 is to have the radio only stay on a control channel long enough to check for activity of interest (to improve the scan rate/performance).
From:
Easier to Read BCD996P2/XT Digital Scanner Manual
(Note: the duplication of entries here is directly from the above reference - some shows up under conventional channels and others show up in trunk system information).
Adjustable Scan/Search Delay/Resume - set a delay up to 30 seconds or a forced resume up to 10 seconds. (per system or search).
Set Delay Time sets the delay (in seconds) the amount of time the scanner stays on a channel after the transmission has ended before moving to the next channel. A negative delay will force a resume after that number of seconds. This setting applies to all channels in the system. You cannot set the delay on a 'per channel' basis. The default setting is 2 seconds.
Scroll to 'Set Delay Time' and press E/.
Scroll to the desired delay time (-10, -5, -2, 0, 1, 2, 5, 10, or 30 secs.) and press E/ to save and exit.
Set Delay Time sets the delay (in seconds) the amount of time the scanner stays on a channel after the transmission has ended before moving to the next channel. A negative delay will force a resume after that number of seconds. This setting applies to all channels in the system. You cannot set the delay on a 'per channel' basis. The default setting is 2 seconds.
Scroll to 'Set Delay Time' and press E/.
Scroll to the desired delay time (-10, -5, -2, 0, 1, 2, 5, 10, or 30 secs.) and press E/ to save and exit.
Set Hold Time sets (in seconds) the amount of time the scanner will scan the site before moving on to the next site. If you select 0 for trunking sites, the scanner stays on the site for at least 1 second. The scanner moves to the next site after the hold time expires, any current transmission ends, and the channel delay time expires. The default setting is 2 seconds for each site.
Tip: set your sites to 0.
Scroll to 'Set Hold Time' and press E/.
Enter the hold time (0-255 seconds) you desire and press E/ to save and exit.
Set Hold Time sets (in seconds) the amount of time the scanner will scan the system before moving on to the next system. All (unlocked) channels will be scanned at least once regardless of this setting. The scanner moves to the next system after the hold time expires, any current transmission ends, and the channel delay time expires. The default setting is 2 seconds for each system.
Tip: set your systems to 0.
Scroll to 'Set Hold Time' and press E/.
Enter the hold time (0-255 seconds) you desire and press E/ to save and exit.
Set Hold Time sets (in seconds) the amount of time the scanner will scan the site before moving on to the next site. If you select 0 for trunking sites, the scanner stays on the site for at least 1 second. The scanner moves to the next site after the hold time expires, any current transmission ends, and the channel delay time expires. The default setting is 2 seconds for each site.
Tip: set your sites to 0.
Scroll to 'Set Hold Time' and press E/.
Enter the hold time (0-255 seconds) you desire and press E/ to save and exit.