3. GENERAL DESCRIPTION
3.1 GENERAL
Unlike most other audiometers, the MIDIMATE 622 has no switches for
selecting fundamental parameters nor potentiometers for calibration of
inputs and patient communication/monitoring functions. Instead these
parameters are selected using the control panel together with the display
while the conventional potentiometers on the rear panel are largely replaced
by electronic level controls.
Test parameters are either preprogrammed and stored in nonvolatile
memory (where stored information is retained when the power supply is cut
off) to be subsequently accessed from the Select User Test menu, or are
selected by pressing Keys 1 to 5. As you press these “softkeys”, the
audiometer responds by displaying different options for your selection. The
resulting test setup is erased on pressing
MENU
. However, if you enable the
“programming” function and select parameters in the same way, you will be
given the option of saving these parameters in the memory as one of the User
Tests.
Test Setup and
Preprogrammed
Tests
It is easier to understand how the test setup process functions if you visualize
it as a series of different levels like a mathematical tree (please refer to Figure
3 on next page). You can use the softkeys to move down through the different
levels of the setup process and the
MENU
button to jump back to the top of
the selection tree and then switch from one branch of the tree to the other.
The Selection Tree
The Connection Panel is located on the rear of the instrument (see page 4 for
installation). In addition to connections, there are two white potentio- meters-
one marked PT to control the level of the audible patient response and the
other for adjusting the display contrast.
Rear Panel
3.2 FRONT PANEL LAYOUT
The front panel layout has been designed for maximum ergonomic efficien-
cy irrespective of whether the operator is left- or right-handed. It has been
subdivided horizontally into 3 parts: the lower is for the manual controls used
during testing and is called the OPERATION subpanel, the central part is the
CONTROL subpanel , the upper part is the DISPLAY subpanel.
Front Panel
The CONTROL subpanel is further subdivided into 3 sections: the central
section is designated “Select” (see next page) and the 2 sections on either
side are designated “Level”. The latter contain pushbuttons which access
electronic level controls for the various speech test inputs (left) and patient-
operator communication (right) with the levels shown on the display. These
electronic controls replace the old potentiometers and are used in
conjunction with the rotary control knobs thus preventing accidental
alteration of preselected levels.
The Control Panel
MIDIMATE 622 OPERATION MANUAL
3. General Description
11
