Kurzweil K250 - Page 37

Front Panel Sub-Assembly
The Front" Panel sub-assembly of' the Kurzweil 250 and the
Kurzweil 250X has three board mounted on the faceplate. They are
the
following: t
Slider board
Control Panel board
LCD board
The
Slider board contains circuitry for the continuous
(smooth-panning)
controls. The Control Panel board controls the
on/off operation of the 55 buttons and the 38 LEOs. The
Control
Panel also
contains an analog/digital converter (ADC) that
translates the analog signals into digital values. The LCD board
controls the liquid crystal display which shows numbers and text.
The Front
Panel sub-assembly of the Kurzweil RMX has one
board mounted
on the faceplate. The assembly is referred to as the
RMX Control Panel board.
POD Assembly (K250 and K250X only)
The POD contains the power supply and the piano-style foot
pedals. Most of the bulk of the POD is the power supply.
The POD contains a 5 volt supply for the system's logic
circuitry, and a ±15 volt supply for the audio circuitry. The newer
POD contains only one printed circuit board.
The
POD assembly also contains a circuit that watches the AC
power line and produces an "advance warning" of imminent power
failure. When this
pulse is detected, the machine saves information
about its current state so that it can resume after the power
interruption.
The POD is discussed further in the Electrical Overview
section.
Kurzwell 250 Service Manual, Chapter 3
3 - 5