Aircraft cabin telephony test unit
View Patent ↗A test unit for an aircraft cabin telephony system includes a pair of connectors for inserting the test unit in-line within the system; an AC voltage module that is operative to indicate the presence of an AC voltage when the test unit is connected to the Cabin Delivery System connector of the cabin telephony system; a signal module that is operative to detect the presence of data signals when the test unit is connected to the Cabin Delivery System connector; a DC power module that is operative to indicate the presence of DC voltage when the test unit is connected to a seat telephony box within the cabin telephony system; and an AC current module that is operative to detect an over-current condition when the test unit is connected to the Cabin Delivery System connector of the cabin telephony system.
1. A test unit for an aircraft cabin telephony system, comprising:
a pair of connectors for inserting the test unit in-line within the system;
an AC voltage module operative to indicate the presence of an AC voltage when the test unit is connected to a Cabin Delivery System connector of the cabin telephony system;
a signal module operative to detect the presence of data signals when the test unit is connected to the Cabin Delivery System connector;
a DC power module operative to indicate the presence of DC voltage when the test unit is connected to a seat telephony box within the cabin telephony system; and
an AC current module operative to detect an over-current condition when the test unit is connected to the Cabin Delivery System connector of the cabin telephony system.
2. The test unit of claim 1 , further comprising:
a relay bank operative to selectively couple the AC voltage module, signal module, and DC power module to the pair of connectors as a function of the AC voltage present on the connectors.
3. The test unit of claim 2 , wherein the signal module comprises means for detecting the presence of E1 signals.
4. The test unit of claim 3 , wherein the AC voltage module comprises:
an AC voltage detect unit having
a window comparator, and
a current source coupled to the comparator.
5. The test unit of claim 4 , wherein the signal module comprises:
an inbound E1 signal module configured to detect the presence of inbound E1 signals; and
an outbound E1 signal module configured to detect the presence of outbound E1 signals.
6. The test unit of claim 5 , wherein each of the E1 signal modules comprises:
a monostable multivibrator configured to lengthen the duration of the pulses of the E1 signal.
7. A method of testing a cabin telephony system, comprising:
removably connecting a portable test unit to a cabin delivery system connector of the cabin telephony system;
indicating a presence of an AC voltage when the test unit is connected to the cabin delivery system connector of the cabin telephony system;
detecting a presence of data signals when the test unit is connected to the cabin delivery system connector;
indicating a presence of DC voltage when the test unit is connected to a seat telephony box of the cabin telephony system; and
detecting an over-current condition when the test unit is connected to the cabin delivery system connector.
8. The method of claim 7 , wherein:
the cabin delivery system connector is located at the junction of a cabin delivery system and a zone telephony box.
9. The method of claim 7 , wherein:
the test unit includes an AC voltage module, an E1 signal module, a DC power module, and a pair of connectors, and further comprising the step of:
selectively coupling the AC voltage module, the E1 signal module, and the DC power module to the pair of connectors as a function of the AC voltage present on the pair of connectors.
10. The method of claim 9 , further comprising the step of:
detecting the presence of inbound E1 signals.
11. The method of claim 10 , further comprising the step of:
detecting the presence of outbound E1 signals.
12. The method of claim 9 , wherein:
the AC voltage module includes a plurality of voltage detect units, wherein each of the plurality of voltage detect units includes a window comparator and a current source coupled to the window comparator.
13. The method of claim 9 , wherein:
the E1 signals include pulses having a duration, and further comprising the step of: lengthening the duration of the pulses.
14. A test unit for a cabin telephony system, comprising:
means for indicating a presence of an AC voltage when a test unit is connected to a cabin delivery system connector of the cabin telephony system;
means for detecting a presence of data signals when the test unit is connected to the cabin delivery system connector;
means for indicating a presence of DC voltage when the test unit is connected to a seat telephony box of the cabin telephony system; and
means for detecting an over-current condition when the test unit is connected to the cabin delivery system connector.