11
Oper
ation
Smoothed Mode - FD2 Only
This mode is used to obtain more stable heart rate readings. In this mode, FHR
is averaged over 8 beats. The LCD displays a solid heart symbol.
Manual Mode - FD2 Only
This mode is used when a fetal heart beat is audible in the loudspeaker or
headphones but, due to noise or a low signal level, the FD2 cannot reliably
calculate the heart rate. In this mode, the heart rate can be manually counted
over a period of 10 audible heart beats (see below). The FD2 will automatically
calculate and display the derived FHR on the LCD. The LCD displays a clock
symbol.
Mode Selection
Press the Mode button to select mode.
Use of Manual Mode (FD2 Only)
1.
Press and hold Start/Stop button and immediately count the audible
heart beats, counting the
fi
rst beat as the button is pressed. The
LCD displays the
fl
ashing clock symbol and the FHR reading is
shown as three dashes.
2.
Release the Start/Stop button immediately on the count of 10 (i.e.
After nine beat intervals). The FD2 will automatically calculate the
derived FHR averaged over the 10 beat period and display the
result. This rate value is retained until the measurement is repeated
or the unit is switched off. If the button is held for a period less than
about 3 seconds the display will clear the previous rate value and
reset.
Connection to Printa II™ (FD2 Only)
Hard copy printing is automatically selected when the plug of the interface buffer
box is inserted into the RS232 socket on the top panel of the FD2. Printing is
then initiated by using the Start/Stop button.
