Connectors; Display And Indicators - Keithley 776 Instruction Manual

MODE FUNCTION
between frequency A. Frequency l3 and Frequency C
functions.
TIME - The TIME push-button sets the Model 776
up to measure one of three time
measurement
functions:
Period A. Pulse A or Time Intenxl A to B. Consecutive
pressing of the [TIME] push-button will toggle be-
tween these three functions.
RATIO -The RATIO push-button places the inslm-
ment in one of three ratio measurement functions: To-
talize B (infinite. gated by A. or gated by AA). FRQlB
(C/B or A/B). or Phase A relative to B. Consecutive
pressing of the [RATIO] push-button will toggle be-
twcen Totalize B. FRC$B. and Phase A to B functions.
1. DISPLAY/MODIFY. The two DISPLAY/MODIFY
push-buttons modify the display from normal fre-
quency. time or ratio reading to another reading such as
trigger level. gate time. totalize mode. V peak mode. or
delay time.
5. INPUTS. There are 5 push-buttons at the INPUTS
section. These buttons select functions which ad.iust
input signal properties before it is applied to the actual
input. Push-buttons control attenuation. coupling.
slope. input impedance. and low pass filter to suppress
high frequency noise.
6. VERNIER. The two push-buttons in the VERN!ER
section are used as a digital potentiometer. The VER-
NIER operates in conjunction with the following func-
tions: Trigger leyel. Gate time. Dela! time. Digits. Ad-
dress. Totalize mode. Vpeak mode. Analog out. and
3-2
Offset. The two push-button also set these parameters
to a pm-set position.
7. SET-UPS. There are tn'o push-buttons in the SET-
UPS section One is used to slorc a complete front panel
set-up. The other button is used to recall a stored set-up.
3-2-2 Connectors
The connectors arc used to connect the Model 776 to the
unknown signal.
1. CHANNEL A. The CHANNEL A connector is used
\\hen making mcasurcmcnt which arc related to channel A.
2. CHANNEL B. The CHANNEL B connector is used
when making measurements which are associated with
channel B.
3. CHANNEL C. The CHANNEL C connector is used
for high frequency measurements. up lo 2.7 GHz with a
50 fi input impedance. Although this terminal is alva!~s
installed. the internal circuitq to operate this function
is optional and ma: not be installed cm your model.
NOTE
If front panel connectors are present
on a Model 776/2.4G/R unit. they are
not functional.
3-2-3. Display And Indicators
1. DISPLAY. The function of the display is to shou the
result of the processed mcaswcmcnt. The display con-
sists of a 10 digit mantissa and a single digit csponcnt.