AMPLIFIER NEEDS SOUND KNOWLEDGE
ZXM is a sound box from Timedata complete with amplifier. Based on the 8912 three-tone chip which appears on most sound boards it also provides a joystick socket. The Atari-type joystick socket will not work with commercial software, as it is based on an I/O port from the 8912 chip and has to be programmed to be available first. The amplifier and loudspeaker are controlled by a volume control situated on the front of the unit.
The unit plugs into the edge connector of the Spectrum and has a PCB edge at the back so that other peripherals can also be plugged-in. The edge connector is only 23 ways wide so it fits both the ZX-81 and Spectrum.
The unit is accompanied by a booklet of programs and a tape. The explanations and use of the unit tend to be over-complicated, requiring a good technical knowledge to understand it.
Timedata also makes a speech unit, ZXS. The unit, plus the software provided, allows you to set up a string (S$) of sounds to make up the words in Basic. A machine code routine will put them out to the speech unit, which also has an I/O-mapped device. Unfortunately you will be unable to hear the speech produced unless the unit is connected to an external amplifier such as the ZXM via its 3.5mm. socket.
The speech can be EDITed and changed using the program but the size of the program may make it difficult to incorporate into your programs.
The ZXM costs £29.95 and the ZXS £24.99 from Timedata. 16 Hemmels, Laindon, Basildon, Essex. Tel: 0268-418121.