Ectron 441A, Instructions Manual, Page: 35 / 74

If the input waveform is sawtooth, then output noise will be best if the slow-rise portion of
the waveform is positive going, and the abrupt fall is negative going. This is true since the
internal conversion circuit of the Model 441A uses the fall time for triggering. However, if
the waveform is the reverse, slow fall and abrupt rise, simply reverse the frequency-input
leads. Since the input is differential, this reversal will not cause noise or ground-loop problems.
UNCERTAINTY AND RESOLUTION
Output analog uncertainty is within
±
0.00122
+



(
1.5
×
10
6 )
f
in
(
1.5
×
10
6 ) −
f
in
−
f
in



×
V
U
−
V
L
f
U
−
f
L
for fre-
quencies less than 1 kHz, and
±
0.00122
+



f
in
2
(
1.5
×
10
6 )
F
×
V
U
−
V
L
f
U
−
f
L



for frequencies of 1 kHz
and above. Output resolution for input frequencies of 1 kHz or below is the greater of
0.0012 V or



f
in
2
1.5
×
10
6
×
V
U
−
V
L
f
U
−
f
L



, resolution for frequencies above 1 kHz is 0.0012 V
Figure 4-2
Worst-case Resolution for Various Frequencies
Model 441A Applications
4-5