Announcement Recording PCB
This PCB is part of the announcement tape deck. To the right are the record/playback head and erase head for this unit. The pink wire ending in a solder tag connects to an insulated part of one of the tape guides, it is thus grounded by a switching foil on the tape at the appropriate time. The PCB contains the switches used to record new announcements on this tape, a DIN socket for the microphone. FETs to select the opening or closing announcement (just below the switches), a bias/erase oscillator (the 2 metal-can transistors) and the microphone preamplifier
Announcement Recording PCB
This PCB is part of the announcement tape deck. To the right are the record/playback head and erase head for this unit. The pink wire ending in a solder tag connects to an insulated part of one of the tape guides, it is thus grounded by a switching foil on the tape at the appropriate time. The PCB contains the switches used to record new announcements on this tape, a DIN socket for the microphone. FETs to select the opening or closing announcement (just below the switches), a bias/erase oscillator (the 2 metal-can transistors) and the microphone preamplifier