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In the grp.txt and ids.txt files of trunker there is an entry called usage. The trunker docs say:
#01 Emergency Call
#02 DES Encrypted Call
#04 Astro or other Digital Call
#08 Encrypted Astro or other Digital Call
#10 Phone Patch <EDACS only>
#20 Digital Phone Patch <EDACS only>

In my files though, I have a, e, and f listed for many talkgroups. What do these mean? Thanks.
Evan