https://www.youtube.com/watch?v=2YT2HgYKasA
The above video will show you how to manually program a trunking system into you scanner. You can look on YouTube for other videos on how to program it. The PRO-651 is programmed the same as any of the following scanners: PRO-106, PRO-197, PRO-651, PRO-652, PSR-500, PSR-600, PSR-651 and PSR-652. Just search YouTube for any of those models.
You didn't mention if you have any software to program your scanner with. It might be easier to use software, especially for a large system. To use software you would need a
programming cable. There are basically three software programs that can program the PRO-652. They are
Win500,
ARC-500 and
PSREdit500. Each of these comes with a 30 trial so you can download all three and decide for yourself which one you like the most. My personal preference is Win500, but they all three will do the job, it's just a matter of which one you're the most comfortable using.