Ja hab ich auch mal angenommen. Aber irgendwie funktionierts nicht.
"Frequency-Shift Keying
The XR-2206 can be operated with two separate timing
resistors, R1 and R2, connected to the timing Pin 7 and 8,
respectively, as shown in Figure 13. Depending on the
polarity of the logic signal at Pin 9, either one or the other
of these timing resistors is activated. If Pin 9 is
open-circuited or connected to a bias voltage >=2V, only
R1 is activated. Similarly, if the voltage level at Pin 9 is
<=1V, only R2 is activated. Thus, the output frequency can
be keyed between two levels. f1 and f2, as:
f1 = 1/R1C and f2 = 1/R2C
For split-supply operation, the keying voltage at Pin 9 is
referenced to V-.
Output DC Level Control
The dc level at the output (Pin 2) is approximately the
same as the dc bias at Pin 3. In Figure 11, Figure 12 and
Figure 13, Pin 3 is biased midway between V+ and
ground, to give an output dc level of V+/2."
Für Pin9 heißt das dann: <=1V wird zu <=(V- + 1V) bzw >=2V zu >=(V- +2V)
?
Hab ich dann ein V- benötige ich diesen Spannungteilerkram an Pin3 ja
nicht, da auf GND bezogen.