BNC PB-5 - Manual (Page 6)

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Hyper Terminal settings:
Flow control: None Data bits: 8 Emulation: VT 100 Parity: None
1.4 MENU SELECTIONS
Figure 2. shows the two level menu employed by the PB-5. The menu is selected by
using the up/down keys on the keypad and pressing enter or by using the spinner/switch
knob. Operating solely by the spinner is most convenient since rotating and depressing
the push switch, all in one motion, makes the menu selection easy.
There are only two levels of menu selection - the main menu and the sub menu. There
are 6 selections on the main menu: TRIGGER MODE, PULSE SETTINGS, RAMP
SETTINGS, SCALE V/keV, SAVE/RECALL, and OPERATING MODE. The sub
menu for each of these selections is shown separately in Figure 2. Four lines of
information are displayed on the LCD at all times (represented by the dotted line in
figure 2). The remaining items are viewed by scrolling up or down. The examples
shown represent the maximum number of significant digits used in determining the
parameter. For example, amplitude accuracy is given to 6 significant digits regardless of
the decimal place (0.00001, 1.00000, 10.0000).
It should be noted that the least significant digit for amplitude might not give the same
number with both the spinner knob and the keypad. Both methods of setting amplitude
are accurate to at least 1 part in 64000, but if repeatability is desired the keypad should
be used. (In the case of the spinner knob the µC calculates the amplitude for every
position and with the same accuracy as the keypad.)
Sub menu items are described in more detail directly below each sub menu. For
example, discrete numbers for all rise time, fall time, and attenuation values are shown
below the sub menu for the pulse settings. Note that many menu settings can be volts or
keV. If using an isotope line for calibration in keV, the instrument will calculate
equivalent volts so that value limits will not be exceeded. When the tail pulse is
selected, rise time and pulse width are removed from the sub menu. This is because rise
time is fixed at 50 ns and width is automatically set to minimum value in this mode.
This insures the best accuracy and repeatability when using a tail pulse.
If there are circumstances that require different rise times, special tail pulses can be
created in the flat-top mode (simply reduce the width to the minimum setting). The last
item in the sub menu allows one to return to the main menu. Alternatively, the key
marked "main menu" on the keypad will also allow a quick return to the main menu.