Sound Plus -56 and vocalizer test points

Sound Plus -56 (Xenon): TP1 +11.9 V, TP2 +5 V, TP3 ground, TP4 0 V when silent and +2.5 V with sound, TP5 2.5 V. Vocalizer board used with the -56: TP1 ground, TP2 +5 V, TP3 analog output, TP4 digital input, TP5 speech clock.

Systems

• Bally MPU AS-2518-35

Games

• Xenon

Related tips

• Sounds Plus -56 and Vocalizer test points (Xenon)
• Background sounds clear but the speech has heavy static: recap and reflow the sound board
• Identifying AS-2518-51 and AS-2518-56 sound boards
• AS-2518-51/-56 sound board jumpers
• Bench-test a -51/-56 sound board with a test EPROM
• No sound at all: start with the amplifier hiss
• Which -51/-56 sound ROMs respond to the board test button
• Sound board chip 86L93 can be replaced by a 74LS93

Source: Voltage Test Points on the Boards