Philips PM 6670 - 3. Operating Instructions; Power, Display, and Basic Controls; Hold Off Function (PM6671); Front Panel Controls and Measurement Modes

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3. Operating Instructions
PM 6671 high resolution timer/counter 120MHz
PHILIPS
TRIGGER LEVEL
SENSITIVITY
O MHi
O GHi
- Z 5V
O O gate MIN
POWER CHECK RESET DISPL
HOLO
OOOO-
I ON
M ST BY
MEASURING TIME
PULSE
WIDTH A
COUNT A
MANUAL
TIME INT L-
SINCLE A-B
AVERAGE A-B
' 96s
PUSH TO READ
PERIOD A
— RPM A
REMOTE ATT SLOPE SOhHi COM SLOPE ATT
kIO FILTER v<a A "L. *10
PHASE A-B
' IN DEGREES
RATIO A/B
MAX 260V_,
KOKI 51
FRONT PANEL
POWER
Supplies power to the counter in the ON, depressed position.
In the ST BY, released position, the counter is switched off, but
power is still available for an optional oven oscillator and a
rechargeable battery. A decimal point marked STBYindicates
the stand-by mode.
This is a secondary power switch. Even in the stand-by
mode the counter contains live conductors and parts.
The line cord (mains lead) must be removed to
disconnect power from the counter.
CHECK
When depressed, the internal 10MHz standard signal is
connected to the logic circuits. In conjunction with the function
selector rotary switch, CHECK enables a self-test of most
measuring functions.
RESET
When depressed, resets the counter and blanks the display.
On release, RESET initiates a new measurement.
DISPL HOLD
When DISPL HOLD is depressed, the display time is set to
infinity. A new measurement can be initiated with the RESET
push-button.
MEASURING TIME
PUSH TO READ
The measuring time can be set between 10ms and 96s for
optimum resolution and measuring speed.
When pushed, the set measuring time is displayed.
HOLD OFF, PM6671 only
During the set hold-off time, the counter ignores all input events
that should have ended the measuring cycle. To display the set
hold-off time, select TIME INT SINGLE A-B and press CHECK.
Function selector rotary switch
RPM A
Sets the counter to perform a revolution per minute
measurement on the signal connected to input A, provided
that the transducer sends one pulse per revolution.
FREQA
FREQ A or C, PM6672 only
Sets the counter to perform frequency measurements on the
signal connected to input A or input C. In the frequency
average mode, rear panel selectable on PM6671...72,
the counter measures the average of several frequency
samples, controlled by an external gate signal via
Input E.
RATIO A/B
Sets the counter to measure the ratio between signals
connected to input A and B up to 10MHz. To obtain full
frequency range on PM6671 ...72, a ratio measurement can
be done in the FREQ A or C mode by using input D set to
EXT STD IN. However, this method does not give correct
setting of the decimal point.
PHASE A-B
Sets the counter to measure the phase (in degrees) between
signals connected to input Aand B. Max frequency is 1.6MHz.
The sensitivity knob should be pulled and set fully clock-wise.
The ATTxlO push-button should be released.
COUNT A MANUAL
Sets the counterto totalize events (pulses or periods) on
input A during the time interval between releasing and
depressing the DISPL HOLD push-button. An event
is defined as a positive-going slope.
The result can be accumulated with another count sequence
or reset with the RESET button.
COUNT A _| 1_ Gated by B
The counter will totalize events on input A, between the leading
and trailing edge of the input B signal.
COUNT A n n Start and Stop by B
The counter will totalize events on input A, between the start
and stop event on input B.
PULSE WIDTH A
Sets the counter to measure the pulse-width of the signal
connected to input A.
TIME INT SINGLE A-B
Sets the counterto measure the time interval between pulses
on input A and B.