ITEC Card Cage
Full view of ITEC card cage. Two ITEC trunks at the left. Seven home made cards at the right.
Card 6: Millwatt tone test line and FM music line.
Card 7: Dial-out tester. This card rings back any line it dials into it.
Card 8: Outside Line answering and coupling circuit. Note thumbwheel switches. Set to autodial line 515 when ever a call comes in from the outside line. The call get routed to whatever line number is set in on the switches.
Card 9: Greeting announcement. This is the announcement that answers line 515. It gives dialing instructions and tells telemarketers their call is not wanted.
Card 10: Interrupter. This uses a crystal oscillator to drive the 60 IPM busy signal, 120 IPM reorder, 2 seconds on and 4 seconds off ringing and the 1 second on, 1 second off, 1 second on, 4 seconds off ringing.
Card 11: 420 Cycle amplitude-modulated by 40 cycle ringback tone (RBT).
Card 12: 480 cycle amplitude-modulated by 120 cycle dialtone. (actually used 474 x 118.5 HZ to match exactly a slightly slow running rotary machine).