Your scanner has 500 channels...50 per bank (10 banks).
Bank 1 (1-50)
Bank 2 (51-100)
Bank 3 (101-150)
Bank 4 (151-200)
Bank 5 (201-250)
Bank 6 (251-300)
Bank 7 (301-350)
Bank 8 (351-400)
Bank 9 (401-450)
Bank 10 (451-500)
While scanning, you will see numbers (1-0) at the bottom of the screen. This shows you which banks are active. If a number is not showing, that bank is turned off. To turn it on again (while scanning), press the associated number key.
To go to a certain channel (say you want to go to bank 7). You press the HOLD button, then press the 3 button then the 0 button then the 1 button and then the HOLD button again. Since channel 301 is the first channel in bank 7, you will now be on channel 301 in bank 7.