Measurement electronics consisting

of *two *separate circuits but installed

in a single chassis (box). Three such

261.5 Ω

152.3 pF

2.49 K

105.8 pF

8.08 K

10.6 pF

boxes were tested, with each box

containing two separate measuring

circuits. For ease of identification,

the boxes were simply called box 2,

box 3, and box 4. For each box, the

two separate measurement circuits

are called probe 1 circuit and probe

circuit 2.

Test circuits as shown in Figure 3

are identified by their actual capaci-

261 Ω

147.2 pF

2.49 K

94.4 pF

8.07 K

16.1 pF

tance value (152.3 pF, for example).

One box (box 3) was left unnulled

in the second set of tests just to pro-

vide some comparison to the nulled

cable measurements.

The initial measurement procedure

consisted of nulling the cable capacitance of the

taken for each circuit and each RC network. As an

test boxes and then connecting each of the test RC

illustration, the raw data from the autumn tests

networks to each measurement circuit (probe 1

are shown in Appendix A. A summary of all the

and probe 2), with readings of Vref, Vdiv, and Vph

test results are shown in Table 2a and b.

152.3 pF circuit

% standard deviation = 5.4

% error = 3.0

10.6 pF circuit

% standard deviation = 14.8

% error = 39.6

105.8 pF circuit

% standard deviation = 0.3

% error = 20.0

152.3 pF circuit

% standard deviation = 2.5

% error = 36.7

10.6 pF circuit

% standard deviation = 4.4

% error = 53.8

105.8 pF circuit

% standard deviation = 2.4

% error = 25.6

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