Abstract: Ink jet printers include orifices which may become clogged or otherwise inoperative. This can cause printing defects which may go undetected for a substantial period because these printers usually operate unattended. An optical detector is provided for testing the operability of each ink jet orifice prior to the beginning of printing either a print cycle or a page. Ink is deposited on a member which moves the deposit through an optical path for detection. Absence of a deposit signals a malfunction.

Abstract: The present invention comprises selectively locating electrical shorting rings on the male section of an optical cable connector. The particular locations of the rings chosen is commensurate with the length of the cable and provides a basis for amplifying the signals being transmitted along the optical cable. On the female section of the cable connector there are electrical contact devices which can be shorted by the rings on the male section if such rings are present. There is a selectable amplifier circuit connected to the optical cable and the contact devices, and depending upon which contact devices are shorted the amplifier circuit provides the proper amplification to the optical signals which are being converted into electrical signals.