Frederiksen Electronic counter User manual

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A/S Søren Frederiksen, Ølgod Tel. [phone] [email protected]
Viaduktvej 35 · DK-6870 Ølgod Fax [phone] www.frederiksen.eu
Manual for Electronic counter
27.09.13 2002.50 AE
INPUTS
In both groups A and B, there are four types of in-
puts. Only one of these are used in each group.
Jack socket
Typically, this input is used with our GM sensors
5135.70 and 5135.65, our Geiger counter 5136.00,
coincidence-box 5138.00 as well as various equip-
ment with Jack plug from Pasco.
DIN connector
This input is used to photocells (1975.50 and
1975.15) and microphones (2485.10) from Frederik-
sen. (Older models of sensors and microphones can
usually also be connected via an adapter.)
Be sure to position the DIN connector
correctly in the socket! It is possible
to brutally force the plug in, even if it
is upside down – which will usually de-
stroy the connected equipment.
Switch input
This entry consists of the left of the two red safety
sockets (signal) and the black (ground). A typical
application is our free fall apparatus, but all types of
switches can be used.
Pulse input
This input consists of the right of the two red
safety sockets (signal) and the black (ground).
All kinds of (positive) electrical pulses can be
used with this entry. (For example, older types of
Geiger counters provide a pulse output with plugs
that match this input.)
Stopwatch
• Simplestart/stop-function
• Velocitiesbeforeandaftercollisions
• Acceleration
• Period
• Frequencycounter
Counter
• Countingwithmanualtiming
• Countingfor1,10,60or100seconds
• Singleorrepeatedcount
QUICK-GUIDE
As a general rule: An LED turned on indicates an
active function. A flashing LED indicates a possible
choice.
Connect a signal source to one of the inputs in
group A (and eventually one in B). The inputs in each
group are equal.
Select the functionbyrapidlypressingtheSelect
button until the desired mode is selected. The func-
tion is selected when you pause (about 1 second).
Counting interval for the Count function: When
Count is selected, continued pressing of the
Select button selects the counting period.
Repeated measurements for Period, Frequency, or
Count: When the Continuous LED is flashing, press
the Memory/Continuous button. The LED lights up
steadily.
Memory: For instance Collision will provide up to
four results. The LED next to the button Memory/
Continuous will flash to indicate that memory con-
tains data. Press the button to switch between them.
Resetting after a measurement is made by pressing
Select once.

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In contrast to the other inputs, the pulse inputs are
not identical; in group A, the pulse input is more sen-
sitive than in group B.
(Inputs are further described in Technical Specifica-
tions.)
OPERATION
Start/Stop
Press the Select button repeatedly until the Start/
Stop LED is lit. The setup is now ready.
The device works like a regular or an electronic stop-
watch. The time can be started and stopped manu-
ally (with the Start/Stop button) or with signals fed to
inputs A and B.
The result is reset by pressing the Select key.
Measurements are stored in the internal memory -
see later.
Collision
This function is used with two photocells and two
cars or carts equipped with a ”tab” that can inter-
rupt the light to the photocell. The device times up
to four such interruptions; this will occur in an elastic
collision on an air track, with the carts first moving
towards each other and then away again.
The four speeds are determined from the tab length,
divided by the time of passage.
Press the Select button repeatedly until the Collision
LED is lit. Wait a moment and press Start/Stop.
The setup is now ready.
The first measurement will remain in the display until
all data is recorded. When the photocells have been
interrupted four times, the first time of passage from
input A is shown. The other times are called up by
pressing Memory/Continuous. Times are marked A1,
A2, b1 and b2 in the display.
If all four passages are not occurring, the series can
be interrupted by pressing the Start/Stop button.
The result is reset by pressing the Select key – wait
a moment, then press Start/Stop. Now the device is
ready for a new collision experiment.
Acceleration
This function is used with two photocells a car or
cart equipped with a ”tab” that can interrupt the light
to the photocell. The device times two such interrup-
tions. Furthermore the time interval between switch-
ing off photocell A resp. photocell B is measured.
The velocities of the cart at two photocells are deter-
mined as the plume length, divided by the passage
time. The average acceleration is determined as the
difference between the two speeds, divided by the
time between the two speed measurements.
Press the Select button repeatedly until the Acce-
leration LED is lit. Wait a moment and press Start/
Stop.
The setup is now ready.
The first test result will remain in the display until all
data is recorded. Once photocell A and then B has
been interrupted, the first passage time of input A is
shown. The other times called up by pressing Me-
mory/Continuous. The times are marked A1, b1 and
Ab.
The measuring series can be interrupted by pressing
the Start/Stop button.
The result is reset by pressing the Select key – wait
a moment, then press Start/Stop. Now the device is
ready for a new acceleration experiment.
Period
This function is used for instance with a photocell
and an object that moves periodically and interrupts
the light in the photo cell. Electrical signals or audio
signals via a microphone can also be measured. Use
input A.
The device can operate in two different modes that
are best explained by a few examples:
With rotating objects you can fit a small ”tab” that in-
terrupts the photocell once per. revolution. The mea-
surement shows directly the period of rotation. This
situation corresponds to mode ”A”.
For pendulums, the amplitude is often so large that
the pendulum swings completely through the pho-
tocell beam twice per period of oscillation. In order
to be able to directly read off the period it is required
that the timer skips every other passage of the pho-
tocell. This situation corresponds to the mode ”B”.
The counter is usually in mode ”A”. To put the unit
into mode ”B”, keep the Select button pressed while
switching on with the On/Off switch. The mode re-
mains unchanged until you switch off again.
In state ”A”, measurements lasts for two oscillations
– the result shown is the average.
In state ”B” – for inscrutable reasons – results are
shown for every third pulse – but the figure corre-
sponds as described to the time between every se-
cond pulse.

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Press the Select button repeatedly until the Period
LED is lit. After a short time the Continuous LED will
flash and normally you will now press Memory/Con-
tinuous to achieve continuously repeated measure-
ments.
Press the Start/Stop button to start the measure-
ment.
Measurements are stored in the internal memory –
see later.
Frequency
This function is used to determine the frequency of
a simple periodic signal. Electrical sine or square
wave signals connected to pulse input A works fine.
In order to work with audio through a microphone,
the sound must be strong and look like a sine wave.
In other words, the sound should be without over-
tones.Soundswithstrongovertonecontentcannot
be used with this counter.
Press the Select button repeatedly until the Period
LED is lit. After a short time the Continuous LED will
flash and normally you will now press Memory/Con-
tinuous to achieve continuously repeated measure-
ments.
Press the Start/Stop button to start the measure-
ment.
Measurements are stored in the internal memory -
see later.
Counts
This function is typically used when working with ra-
dioactivity. Use input A.
With the Count function, the measurement time in-
terval must be selected. A typical time interval for
demonstration tests and many student labs is 10 s.
Accurate measurements may require longer intervals
like 60 s or 100 s. Even longer time intervals can be
achieved by simply making multiple measurements
and adding the results. If very long measurement pe-
riods are necessary, you can use manual start and
stop.
Press the Select button repeatedly until the Count
LED is lit. Afterwards the Select button switches bet-
weenthepossibletimeintervals.“Start/Stop”means
manual start and stop, the setting “Special” is not
used.
Shortly after you select the measurement period,
the Continuous LED flashes and normally you will
now press the Memory/Continuous to achieve conti-
nuously repeated measurements. Measurements will
be stored in the built-in memory – see later.
Press the Start/Stop button to start the measure-
ment.
When in continuous mode, the counting initially runs
for, say, 10 seconds. Next, the result is displayed for
3 seconds while the next measurement is already
underway. The next 7 seconds of the counting is fol-
lowed ”live”, and then the result is displayed for 3
seconds – etc.
The shortest counting interval leaves no time for
readout, but the data can later be retrieved from
memory.
After a single measurement, the display is reset by
pressing Select once. The unit is now ready for a
new measurement.
A Continuous series of measurements is terminated
by pressing the Start/Stop button. The current mea-
surement continues until the end before stopping.
Instant stop is achieved by pressing Select.
Memory
The functions Collision and Acceleration use the
memory as described previously.
All the other functions continuously save the
results in memory. There is access to browse the
memory when the LED next to Memory/Continuous is
flashing. This requires that a measurement is not in
progress.
Each press of the button Memory/Continuous steps
”backwards” from newest to oldest results. When
you have reached the end, the symbol ”--------” is
displayed; after that the sequence is started over
again.
There is room for 50 numbers in memory, oldest
entries will be overwritten.
Pressing Select resets the memory.

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TECHNICAL SPECIFICATIONS
Jack connector
Theexternalequipmentispoweredby 5V(max.1
A), delivered to the Tipoftheplug.Seegure.
The Ring of the plug is the signal fed into
the counter.
Triggering occurs on the falling
slopeatc.2V.
The Sleeve is ground
The DIN connector
1. Ground
2.+8V
3. Photo
4.6.3VAC
5.6.3VAC
6. Microphone
The two supply voltages have a max. load of 1 A.
The Microphone input triggers on the falling slope
atc.0.5V.Sensitivitycanberaisedabout10dBby
shorting the Photo input to ground.
Apart from this, the Photo input is strongly specia-
lized for use with Frederiksen’s photocell units.
Switch input
Triggering occurs on the
rising slope – i.e. when the
switchbreaks–atc.1.2V.
When the switch is open,
the input is pulled up to
c. 7.4 V which must be ta-
ken into account if an elec-
tronic switch is used instead
of a mechanical one. The
generator impedance is c. 7.6 kΩ.
Pulse input
Triggeringoccursonafallingslopeatc.70mV(input
A)resp.1.7V(inputB).Themaximumpeakvoltage
toleratedis50Vresp.100VforinputsAandB.
Mains power
Thecounterispoweredby230VAC
The unit must be grounded and is provided with a
grounded power cord.