Don't know how.
VR202 is the modulation adjust but you still need some way to monitor your progress. According to DTB Radio's email to me about my Royce 604 I had him tune,the AMC is very slow to react and the compressor will kick in so you might end up pulling your hair out if you don't have the equipment to properly adjust your radio. Sending your radio to DTB Radio for diagnosis and tune and align will have it purring like a kitten.
CB Services and Prices
I had a chance the other day to purchase a NIB/NOS Royce 619. I didn't jump I. It fast enough.