Key outputs – Expanded IFB Option
Four
Table 2.7 Auxiliary connector, J22.
PIN # | FUNCTION |
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6 | CH 1 or four wire CH A key output |
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7 | CH 3 or |
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19 | CH 2 key output |
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20 | CH 4 key output |
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There are internal
The channel three and four key outputs may also be used to expand the IFB function, allowing any one of several MCE325 User Stations to interrupt a
Remote Microphone Switch
A remote microphone switch may be connected at the auxiliary connector. Connect mic switch high to pin 25; connect mic switch low to pin 10 or 11. When the switch is closed, the microphone will turn on, and the front panel MIC ON LED will illuminate. When the remote switch is off, the microphone may be turned on from the front panel. When the remote switch is on however, the microphone cannot be turned off from the front panel.
ISO Connection
To connect an RTS Model VCP6A, VCP12A, or VCP12B ISO Control Panel to the MCE325, connect the unswitched microphone output of the MCE325 (pins 1 and 14 of the auxiliary connector) to the
External Headset
An external headset may be connected to the auxiliary connector. (See “Headset Requirements”.) Connect headphone left to pin 5, headphone right to pin 18, and headphone common to pin 17. Connect microphone high to pin 4; connect microphone low to pin 16. The external headset connections are wired in parallel with the front panel dynamic headset connector; therefore, use only one at a time.
In the headset connecting cable, prevent coupling between the microphone and headphone leads by using a shielded twisted pair for the microphone, and a separate shielded twisted pair for the headphones. Do not allow headphone common to contact microphone low. Tie the headphone shield to headphone common. The headset cable can be made longer when the microphone and headphone pairs are physically separated. The wider the separation, the longer the allowable cable length. Estimated maximum usable headphone cable lengths are as follows:
Single cable, two shielded twisted pairs: 10 feet (3.05 m).
pairs: 30 feet (9.14 m).