Ever had a problem when swapping crystals?
Thomas,
That paragraph is speaking of transmitters with the very plug in frequency modules you recommend. It says that all components must be inside the module and that the crystal must not be accessible to the user. It does not say that there cannot be a user accessible module on the TRANSMITTER!
The FCC does not intentionally certify equipment which does not comply with its regulations. So why did they certify radios from all manufactures with user accessible crystals? Why does Multiplex claim that the users of their radios swap the crystal without breaking the law?
It may be that the radio manufactures got sued at some time because the radio crystal was swapped by the user and that radio failed causing injury or property damage. But I cannot see anything in that reg that says it's against the law!