6K V1.02 03-16-91
89
AUTOPATCH
REVERSE PATCH - TRIGGER
Command Form:
(PW) 87 *
Description:
The Reverse Patch feature allows users to dial the repeater telephone
number from a landline and be connected to a repeater user. The Reverse
Patch can be used in two ways: the controller can announce that a user has
dialed the site, or the controller can wait for a DTMF command from the
telephone party before announcing. In the first mode, the telephone party
never has access to the DTMF decoder; the only function that a call to the
repeater telephone number has is to trigger a reverse patch message. In
the second mode, the telephone party is similar to a control operator; he will
be able to enter any command. To trigger a reverse patch, the proper
command will have to be entered from a Touch Tone telephone.
The first mode may be necessary in several situations. For example, in
areas without Touch Tone service, the controller will have to be configured
to trigger a reverse patch message without requiring a command. Other
exchanges reverse the polarity of the telephone line loop voltage going to
the telephone set after the dialing process is complete; this disables the
DTMF encoder in the telephone. These situations can be fixed by using a
separate DTMF encoder in the first case, and using a bridge rectifier to feed
unipolar DC to the DTMF encoder in the second case. However, it will still be
difficult to trigger the reverse patch from some pay phones (or a phone not
equipped with DTMF capability) in rotary exchanges.
When the Reverse Patch Trigger command is entered from the landline, the
command causes the reverse patch sequence to start. The DTMF decoder
is switched from the landline back to the repeater receiver. Note that this
command only works from the landline, and that the error message is sent to
the landline.
Acknowledgement:
Starts Reverse Patch sequence, sends Ringout Message
Errors:
? ERR 1
wrong number of digits entered
Default Condition:
none