It around 72MHz wide-band FM. It is a "setting" in that different units can have different channels if they are close together, but mostly they use just one common channel.
Sorry, I don't have the details in front of me.
Edit: Note that the church has used two different suppliers.
Comtek and
Williams Sound.
In our case the Comtek was installed in the chapel and Williams was provided later for language translation. I don't know if the church changed suppliers or not. Both operate on the same frequencies, but I'm not sure as the are interoperable.
The last time I called Comtek, the engineer knew off the top of his head the common LDS frequency.
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