TIME-A (Interval) Measurements

3.3.2

A. Readout - The display for all conditions in the TIME-A mode is in actual units of time (i.e., seconds,

microseconds, etc.). The specific units and implied decimal point location are a function of the

multiplier switch setting as defined in paragraph C below.

B. Thumbswitches (Period Selection) - In the TIME-A mode, the thumbswitches serve to select the

number of cycles, periods, or "N" events of the input signal over which the time base oscillator will

be counted. For example, a thumbswitch setting of .000355 means that the readout will show the

total number of internal clock pulses that have been accumulated during 355 cycles of the input

signal. Note that the front panel decimal point is ignored in this mode. For single period

measurements, the thumbswitches should be set to 1 (actual setting of .000001). For multiple or

average period measurements, the thumbswitches are usually set in decade multiples, 10, 100,

1000, etc. The total range of periods is from 1 to 1,000,000. To arrive at the time for one period,

the number shown on the display must be divided by the thumbswitch setting.

C. Multiplier (Time Resolution)

The multiplier switch selects the internally generated clock frequency counted in this mode and,

therefore, determines the resolution of displayed time.

Toggle Switch

Clock

Time

Setting

Increment

100 KHz

XXXXX.X ec

X10

10 KHz

100

XXXX.XX ec

X100

1 KHz

1000

XXXXXX msec

X1000

100 Hz

10 ms

XXXX.XX sec

Therefore, each count appearing on the readout indicates a time lapse of 10 ec, 100 ec, 1000

ec or 10 msec. depending upon the setting. The location for decimal points, when reading the

display, must be mentally noted similar to those shown in the table.

3-5