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GE864 Hardware User Guide
1vv0300694 Rev.10 - 10/06/08
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 39 of 69
9 Audio Section Overview
The Base Band Chip of the GE864-QUAD / PY Telit Module provides two different audio blocks; both
in transmit (Uplink) and in receive (Downlink) direction:
“MT lines” should be used for handset function,
“HF lines” is suited for hands –free function (car kit).
These two blocks can be active only one at a time, selectable by AXE hardware line or by AT
command. The audio characteristics are equivalent in transmit blocks, but are different in the receive
ones and this should be kept in mind when designing.
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