Pendulum FDA-301A User manual

U S E R M A N U A L
Part No.:
Revision:
Date:
4031.604.66041
1
29.03.2023
Frequency Distribuon Amplier
FDA-301A
© 2023 Pendulum Instruments.
All rights reserved.

PREPARATION
FOR USE
Safety
Introducon
Please take a few minutes to read through this part of the
introductory chapter carefully before plugging the power cable
into the wall outlet. This instrument has been designed and
tested for Measurement Category I, Polluon Degree 2, in
accordance with EN 61010-1:2011 and EN 61326
:2013, increased test levels according to EN 61000-6-2:2008,
Group 1, class B, CE. It has been supplied in a safe condion.
Study this manual thoroughly to acquire adequate knowledge
of the instrument, especially the secon on Safety Precauons
hereaer and the secon on Installaon on next pages.
Safety Precauons
All equipment that can be connected to line power is a potenal
danger to life. Handling restricons imposed on such equipment
should be observed. To ensure the correct and safe operaon of
the instrument, it is essenal that you follow generally accepted
safety procedures in addion to the safety precauons specied
in this manual. The instrument is designed to be used by trained
personnel only. Removing the cover for repair, maintenance,
and adjustment of the instrument must be done by qualied
personnel who are aware of the hazards involved.
The warranty commitments are rendered void if unauthorized
access to the interior of the instrument has taken place during
the given warranty period.
Cauon and Warning Statements
CAUTION: Shows where incorrect procedures can cause damage
to, or destrucon of equipment or other property.
WARNING: Shows a potenal danger that requires correct
procedures or pracces to prevent personal injury.
Shows where the protecve ground terminal is connected
inside the instrument.
Never remove or loosen this screw.
This symbol is used for idenfying the funconal ground
of an I/O signal. Is always connected to the instrument
chassis.
If in Doubt about Safety
Whenever you suspect that it is unsafe to use the instrument,
you must make it inoperave by doing the following:
• Disconnect the line cord
• Clearly mark the instrument to prevent its further operaon
• Inform your Pendulum-Instruments representave.
For example, the instrument is likely to be unsafe if it is visibly
damaged.
2
GENERAL
INFORMATION
About this Manual
This manual contains instrucons on how to install and use the
FDA-301A Frequency Distribuon Amplier.
Warranty
The Warranty Statement is part of the folder Important
Informaon that is included with the shipment.
Declaraon of Conformity
The complete text with formal statements concerning product
idencaon, manufacturer and standards used for type tesng
is available on request.
PREFACE
Introducon
Congratulaons on your choice of instrument. It will serve you
well for many years to come. Your instrument is designed to bring
you the most ecient way of distribung a reference frequency
and pulsed signals. It gives signicantly increased performance
compared to tradional Distributors of signals. The FDA-301A
oers the following advantages:
• Mulple signal types:
• Low noise sine wave (default 10MHz)
• Timing reference signals, 1-pps and IRIG DCLS
• Serial ToD
• Distribuon via opcal ber or electrical coax
• No noise pick-up, no ground current loops and up to 2km
range using ber
• Three modular output boards providing up to 12 coax, or 18
ber outputs
• Power source redundancy: AC and oponal DC power
Powerful and Versale Funcons
A unique feature of your new instrument is modularity. The
output signal cards are interchangeable, which allows for any
conguraon chosen by the user without the need to send
the instrument to the manufacturer. One of the advantages of
distribuon via ber is transmission to remote sites, over long
distances, up to 2 km.

3
Environmental Consideraons
This secon provides informaon about the environmental
impact of the product.
Product End-of-Life Handling
Observe the following guidelines when recycling an instrument
or component:
Equipment recycling
Producon of this equipment required the extracon and use
of natural resources. The equipment may contain substances
that could be harmful to the environment or human health if
improperly handled at the product’s end of life. To avoid release
of such substances into the environment and to reduce the use
of natural resources, we encourage you to recycle this product in
an appropriate system that will ensure that most of the materials
are reused or recycled appropriately.
This symbol indicates that this product complies with
European Union requirements according to Direcves
2012/19/EU and 2006/66/EC on waste electrical and
electronic equipment (WEEE) and baeries.
Baeries
This product does not contain any built-in baery
Unpacking
Check that the shipment is complete and that no damage has
occurred during transportaon. If the contents are incomplete
or damaged, le a claim with the carrier immediately. Also nofy
your local Pendulum sales or service organizaon in case repair
or replacement may be required.
Check list
The shipment should contain the following:
• FDA-301A with opons installed according to your ordered
conguraon
• Line cord
• Important Informaon fact sheet
• Cercate of Calibraon
• CD including the following documentaon in PDF format:
• User’s Manual
The actual conguraon of your ordered instruments is readable
from the last 5 digits in the “NC” eld of the product label on the
rear panel.
NC: 9446 130 XYZZZ
X = Input opons
Y = Power opons
Z = Output opons (3 slots)
X=1: 10 MHz only (std) X=2: 10 MHz, pulse X=3: 10 MHz, ToD
X=5: 10 MHz, pulse + ToD
Y=1: AC power
Y=2: AC + DC power
Z=0: module not installed
Z=1: 4x10 MHz coax Z=2: 6x10 MHz ber Z=3: 4x pulse coax
Z=4: 6x pulse ber Z=5: 4x ToD electrical
Example: NC = 9446 130 11021 = FDA-301A with 10 MHz
input only (X), no DC opon (Y) plus one empty output slot, one
6x 10 MHz ber output, and one 4x 10 MHz coax output (ZZZ).
Installaon
Type number and Serial number
The products type number label, including the conguraon
(NC) and the serial number (SN), is the best way for Pendulum
Instruments to idenfy the product. If the serial number is not
noted on your delivery notes, please add the serial number to
your own product documentaon. This will be useful at future
contact with Pendulum Instruments.
Supply Voltage
Seng
The Frequency Distribuon Amplier may be connected to any
AC supply with a voltage rang of 90 to 265 Vrms, 45 to 440Hz.
The Frequency Distribuon Amplier automacally adjusts itself
to the input line voltage.
Fuse
The secondary supply voltages are electronically protected
against overload or short circuit. The primary line voltage side
is protected by a fuse located on the power supply unit. The
fuse rang covers the full voltage range. Consequently there is
no need for the user to replace the fuse under any operang
condions, nor is it accessible from the outside.
CAUTION: If this fuse is blown, it is likely that the power supply
is badly damaged. Do not replace the fuse. Send the Frequency
Distribuon Amplier to the local Service Center.
Removing the cover for repair, maintenance and adjustment
must be done by qualied and trained personnel only, who are
fully aware of the hazards involved.
The warranty commitments are rendered void if unauthorized
access to the interior of the instrument has taken place during
the given warranty period.
Grounding
Grounding faults in the line voltage supply will make any
instrument connected to it dangerous. Before connecng any
unit to the power line, you must make sure that the protecve
ground funcons correctly. Only then can a unit be connected to
the power line and only by using a three- wire line cord. No other
method of grounding is permied. Extension cords must always
have a protecve ground conductor.
CAUTION: If a unit is moved from a cold to a warm environment,
condensaon may cause a shock hazard. Ensure, therefore, that
the grounding requirements are strictly met.
WARNING: Never interrupt the grounding cord. Any interrupon
of the protecve ground connecon inside or outside the
instrument or disconnecon of the protecve ground terminal is
likely to make the instrument dangerous.

4
Powerswitch
There is no power switch in this Distribuon Amplier. The unit
is automacally powered when connected to an AC source. It
is also automacally powered when connected to a DC source,
when opon 49 is installed.
OrientaonandCooling
The Frequency Distribuon Amplier can be operated in
any posion desired. Make sure that the air ow through the
venlaon slots at the side panels is not obstructed. Leave 5
cenmeters (2 inches) of space around the unit.
Fold-DownSupport
For bench-top use, a fold-down support is available for use
underneath the counter.
RackmountAdapter–oneinstrument(Opon22/90)
This rackmount adapter can hold any standard Pendulum ½ * 19”
unit, like FDA-301A, CNT-9x, GSG-5, GSG-6, GPS-12x etc.
If you have ordered the Opon 22/90, 19-inch rack-mount kit
for one instrument, it has to be assembled aer delivery of the
instrument.
The rackmount kit consists of the following:
• 2 brackets, (short, le; long, right)
• 4 screws, M5x8
• 4 screws, M6x8
AssemblingtheRackmountKit(Opon22/90)
• Turn the device upside down
• Remove the rubber feet in the plasc stand
• Loosen the screws underneath the rubber feet
• Remove the plasc stands
• Remove the four decorave plugs that cover the screw holes
on the right and le side of the front panel.
• The long bracket in Opon 22/90 has an opening so that
cables for Input signals can be routed inside the rack.
• Mount the rackmount kit with the included screws
ReversingtheRackmountKit
The instrument may also be mounted to the right in the rack. To
do so, swap the posion of the two brackets.
RackmountAdapter–twoinstruments(Opon22/05)
This rackmount adapter can hold any two standard Pendulum ½
* 19” unit, like FDA-301A, CNT-9x, GSG-5, GSG-6, GPS-12x etc.
If you have ordered the Opon 22/05 rack-mount kit for two
instruments, it has to be also assembled aer delivery of the
instrument. The rackmount kit consists of the following:
• 4 Brackets, rear
• 1 Hinge Spring Latch

5
• 2 Ear, rack
• 1 Assembly instrucon, SXS Rack kit
• 2 Screws M4x8
• 8 Screws M5x10
• 1 Spacer M4x16
AssemblingtheRackmountKit(Opon22/05)
• Turn the devices upside down
• Remove the rubber feet in the plasc stand
• Loosen the screws underneath the rubber feet
• Remove the plasc stands
• Remove the four decorave plugs that cover the screw holes
on the right and le side of the front panel.
Use the following steps to complete the side by side rack mount
installaon for your products. If necessary, refer to the item
numbers in the following diagram for addional detail.
• Determine where you would like each unit posioned (i.e.,
on the right or le side)
• If plugs exist on the mounng holes on the front le and
right side of product cover, remove and discard them
• Using screwdriver, screw the rack ear (Item #2) into place
using the supplied 10mm screws (Item #5)
• Pinch the hinge pins together to separate the right and le
hinge halves (Items #3 and 4)
• Aach hinge halves to the unit with hinge facing towards
the front (as displayed in diagram)
• Using a screwdriver, remove the exisng rear brackets on
the back of each unit
• Using exisng machine screws removed in previous steps,
aach the rear brackets supplied with the mounng kit (Item
#1)
• Pinch the hinge pins together into the stored posion. Align
the hinge halves together between the two units, and swing
together side by side. The hinge pins should snap into place
securing the front of the two units together
• Take the supplied Hex Spacer (Item #7) and place between
middle rear brackets, and secure using the supplied 8mm
screws (Item #6)
• Assembly is now ready for installaon into standard 19” rack

6
USING THE
CONTROLS
The purpose of the Frequency Distribuon Amplier is to
distribute a stable reference signal, or a ming/synchronizaon
signal, from the source to one or more remote receivers. It can
also act as an Electrical-to-Opcal signal converter or Opcal-
to-Electrical converter
The operaon of the Frequency Distribuon Amplier is
extremely simple. There are no sengs controls whatsoever on
the FDA-301A, not even a power switch. The operaon is truly
plug-and-play. Just plug in the FDA-301A to the mains power,
and connect your input source – coax or ber – to the relevant
input connector.
Front Panel – Inputs
Every signal type input has dual connectors, one BNC coax
connector on top, for connecng an electrical signal, and an ST-
ber connector below for connecng an opcal signal. The ToD
input has two idencal 6-pole mini-DIN connectors.
Your actual conguraon depends on the ordered opons.
Non-ordered opons will have a plasc cap at their front panel
posion, stang “Opon not installed”
LED – status
LED indicators are located on the front panel of the instrument.
They can individually take the state of red or green.
Green input LED indicates that the input has detected a signal
within the input limits. Signal is good.
Red input LED indicates that the input signal is outside the input
limits, as when there is no signal aached. Red also indicates that
the signal path for this input is blocked.
The Power indicators show the status of the power supplies. If
DC power supply opon is not installed, that LED is always Red
If LED’s are turned o/black, there is no power supplied to the
FDA-301A.
Note that the Input Status indicators do not evaluate the quality
of the input signals, only the amplitude.
Rear Panel – Outputs
The rear panel contains three slots for up to three output
modules, the AC input power connector, and the +24V DC input
power connector (if opon 49 is installed).
The example below shows one mounted 10MHz coax output
signal module, and two unused slots. If you want to use more
modules, you must remove the scker on the rear panel, carefully
insert a new module into the slot using the guide rails, and fasten
with the included screws. It does not maer in which posion
the modules are inserted.
The output modules could be for the same signal type, e.g. sine,
or for dierent signal types, distributed in parallel, e.g. sine AND
pulse.
The output modules could be a mix of ber or coax outputs
Signal types
Sine
The Sine input channel is intended for narrowband reference
frequency distribuon. The signal path is bandpass ltered to
reject frequencies other than the desired.
The default sine frequency is 10 MHz, but FDA-301A could
be modied to distribute other common reference frequencies
instead, from 200 kHz up to 40 MHz. Please contact Pendulum
Instrument about desired frequency, before ordering.
The input signal range is from 0.2 to 2Vrms, and the output
signal level is 1Vrms nominal into 50 ohm.
Pulse
The Pulse input channel is intended for distribuon of broadband
ming reference or synchronizaon pulses from 1 Hz to 20 MHz.
Example of ming reference pulse signals are 1-pps and IRIG
(DCLS). The input and output signal range is TTL-levels into 50
ohm
Time of Day
The Time of Day (ToD) channel is intended to distribute me
code messages, e.g. in NMEA format, to mulple users over RS-
232.
The connectors are of Mini Din type, 6 pins Female. Unlike the
other signal types, there is no long range ber distribuon
Pin number of connector:
1: Reserved
2: Reserved
3: Electrical ground
4: NC
5: Electrical ground
6: Message input (level RS232C, ASCII
message)
Start and Usage
Power on
Connect the power supply to the instrument using the included
power cord. Allow FDA-301A to warm- up for some minutes.
Wait to connect ber or coax signal to the inputs unl Input
Status indicators are red.
The unit should normally always be connuously powered. The
only instance when power should be disconnected is when
adding or replacing output modules.

7
Input signals can be added, removed or changed without any
power o.
Input source redundancy with auto-changeover
The FDA-301A can be congured for automac change-over of
the input source. Then the Master reference shall be connected
to the lower ber port, and the Slave reference to the upper coax
port.
As long as both inputs signals are valid, and the coax and ber
LED’s are green at the same me, the ber input has priority and
is used for distribuon. The coax input signal path is internally
blocked. If the Master reference should fail, the Slave reference
at the BNC-input automacally takes over.
If valid ToD signal levels are detected at both ToD input
connectors, meaning both LEDs are Green, then the lower
input will be used and the signal path of the upper connector is
internally blocked.
Power supply redundancy with auto-changeover
When the DC power supply opon, Opon 49, is installed and
connected to +24V, the FDA-301A is set- up for automac
change-over of the power source. Normally, the internal
secondary power voltages are generated from the AC supply,
but in the case of a power line failure, the DC supply opon
automacally takes over. When the power line is restored, then
internal power via the AC supply is resumed.
Conguraon examples
There are no parameters to be congured or set.
The FDA-301A can be used in many distribuon situaons. For
example:
• Local Coax distribuon (coax in – coax out) to up to 12 users
(1 FDA-unit)
• Remote Coax distribuon (coax in/ber out – ber in/coax
out) to up to 216 users (mulple FDA-units)
• Electrical to Opcal conversion and spling
• Opcal to Electrical conversion and spling
• ToD distribuon to mulple users
Some typical examples of possible distribuon conguraons
are listed below
A: Local distribuon of a 10 MHz reference via
coax to 12 local users
Each user receives 1x 10 MHz
3 coax (sine) output slots used in FDA-301A
B: Local distribuon of a 10 MHz & 1-pps via
coax to 8 local users
4 users receives 1x 10 MHz sine and 1x 1-pps pulse
4 users receive 1x 10 MHz sine only
2 coax (sine) output slots used in FDA-301A
1 coax (pulse) output slot used in FDA-301A
C: Remote distribuon of 10 MHz, 1 site, 12
users
Each user receives 1x 10 MHz
1 ber (sine) output slot used in 1 transmier FDA-301A
3 coax (sine) output slots used in 1 receiver FDA-301A
D: Remote distribuon of 10 MHz, 6 sites, 72
users
Each user receives 1x 10 MHz
1 ber (sine) output slot used in 1 transmier FDA-301A
3 coax (sine) output slots used in 6 receiver FDA-301A
E: Remote distribuon of 10 MHz & 1-pps, 6
sites, 24 users
24 users receives 1x 10 MHz sine and 1x 1-pps pulse
2 ber (1x sine + 1x pulse) output slots used in 1 transmier
FDA-301A 2 coax (1x sine + 1x pulse) output slots used in 6
receiver FDA-301A

8
G: Remote distribuon of IRIG DCLS me code,
6 sites, 72 users
72 users receive 1x IRIG DCLS signal
1 ber (pulse) output slot used in 1 transmier FDA-301A
3 coax (pulse) output slots used in 6 receiver FDA-301A
Input and output connectors
Fiber Opc Ports
The ber opc connectors are of ST type. The quality of the
signal depends on the aenuaon of the ber opc cable and
splices.
It is therefore essenal to keep the aenuaon low. Patch cables
and splices should be kept as few as possible. Connectors shall be
kept clean. Use a dry clean coon cloth, or similar, for polishing.
If alcohol or any other soluon is used for cleaning, always polish
with a dry cloth, to make sure that there is no residue le.
The AGC can control up to 8dB in link aenuaon, which
equals approximately 2km ber. Two or more FDA-301A can be
cascaded to extend link length.
BNC Ports
When using coaxial cables for distribuon, there is always a
potenal risk for ground current loops, since the coax cable
shield is connected to the instrument chassis ground at both
ends of the cable. Ground current loops occur when the ground
potenal at the receiver is dierent from the ground potenal at
the transmier. This occurs for example when the transming
and receiving ampliers are connected to dierent electrical
switchboards. Ground current loops may add addional noise to
the transmied signal.
To prevent ground current loops, the BNC-ports can be isolated
from the chassis ground, meaning just one grounding point of
the transmission cable shield, instead of two
All BNC-ports are referenced to FDA-301A chassis at delivery.
There are insulaon washers supplied with each FDA-301A, to
insulate the BNC connector housing from the chassis.
All BNC ports can be individually congured to be insulated.
Both the input ports and the output ports can be isolated
Congure as follows:
• Loosen nut at BNC – 14mm nut.
• Pull out the factory-ed washers.
• Add one of the insulaon washers delivered with the FDA-
• 301. The insulaon washer must be mounted closest to the
panel.
• Reassemble the washers and the nut as in the picture. Use
gentle force while ghtening the nut.
QUICK
PERFORMANCE
CHECK
This performance procedure is intended for incoming inspecon
to determine the acceptability of newly purchased instruments,
or whenever a quick test is convenient.
Note: The procedure does not check every facet of the
instrument. It is concerned primarily with those parts of the
instrument which are essenal for determining the funcon of
the instrument.
Note: This Frequency Distribuon Amplier does not need to be
sent away for calibraon. The instrument contains no parts that
are subject to ageing.
It is not necessary to remove the instrument cover to perform
this procedure.
Recommended Test Equipment
• Oscilloscope with 50 ohm input
• Pendulum CNT-90 mer/counter/analyzer
• A low noise signal generator for sine waves 200 kHz to 40
MHz
• A pulse generator 1Hz to 20 MHz with fast rise me
• An opcal power meter
• Short opcal mulmode ber cable with ST-connectors, 2-5
meter
Power On test
• Connect the power plug to the rear panel of FDA-301A (No
input signals connected)
• Verify that the AC power diode goes green, and the fan
starts
• Verify that the input signals diodes goes red
Check of one Distribuon unit
in local mode (coax in/coax out)
Sine input coax test
Connect output signal from Signal generator to sine input of the
FDA-301Aunit
• Set sine signal; 10MHz frequency and amplitude 1Vrms on
generator
• Verify that sine signal diode goes green

9
• Set sine signal; 10MHz frequency and amplitude 0.2Vrms
on generator
• Verify that sine signal diode goes green
• Set sine signal; 10MHz frequency and amplitude 2Vrms on
generator
• Verify that sine signal diode goes green
Pulse input coax test
• Connect output signal from pulse generator to pulse input
of the FDA-301A unit
• Set 1Hz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
• Set 10MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
• Set 20MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
Sine output coax test
Connect output signal from signal generator to sine input of the
FDA-301A unit
• Connect signal from the FDA-301A sine coax output module
to input of the Oscilloscope (Use 50Ω terminaon)
• Set 10MHz frequency and amplitude 1Vrms sine signal on
signal generator
• Verify using oscilloscope that the amplitude is 1Vrms ±10%
(Vpp = 2.8V ±10%), and that the waveform of the signal is
not visibly distorted
• Set 10MHz frequency and amplitude 0.2Vrms sine signal on
signal generator
• Verify using oscilloscope that the amplitude is 1Vrms ±10%
(Vpp = 2.8V ±10%), and that the waveform of the signal is
not visibly distorted
• Set 10MHz frequency and amplitude 2Vrms sine signal on
generator
• Verify using oscilloscope that the amplitude is 1Vrms ±10%
(Vpp = 2.8V ±10%), and that the waveform of the signal is
not visibly distorted
Pulse output coax test
• Connect output signal from Pulse generator to the pulse
input signal of the FDA-301A
• Connect signal from the FDA-301A pulse coax output
module to input of the Oscilloscope (Use 50Ω terminaon)
• Connect signal from the FDA-301A pulse coax output
module to input of CNT-90 (Set input impedance 50Ω and
DC)
• Set 1Hz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V pulse signal on generator
• Verify using CNT-90 that the output frequency signal is 1Hz,
the High-level is 5V ±0.5V, and the Low-level is 0V ±0.5V.
• Verify using the oscilloscope that the waveform of the signal
is a pulse shape with overshoot/undershoot <20% of Vpp
• Set 10MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V pulse signal on generator
• Verify using CNT-90 that the output frequency signal is 10
MHz, the High-level is 5V ± 0.5V, and the Low-level is 0V
±0.5V.
• Verify using the oscilloscope that the waveform of the signal
is a pulse shape with overshoot/undershoot <20% of Vpp
• Set 20MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V pulse signal on generator
• Verify using CNT-90 that the output frequency signal is 20
MHz, the High-level is 5V ±0.5V, and the Low-level is 0V
±0.5V.
• Verify using the oscilloscope that the waveform of the signal
is a pulse shape with overshoot/undershoot <20% of Vpp
Check of two FDA-301A
Distribuon Ampliers with
ber in between (coax–ber–
coax)
Sine input coax test - transmier unit
• Connect output signal from Signal generator to sine input of
the FDA-301Aunit
• Set sine signal; 10 MHz frequency and amplitude 1Vrms on
Signal generator
• Verify that sine signal diode goes green
• Set sine signal; 10 MHz frequency and amplitude 0.2Vrms
on Signal generator
• Verify that sine signal diode goes green
• Set sine signal; 10 MHz frequency and amplitude 2Vrms on
Signal generator
• Verify that sine signal diode goes green
Pulse input coax test – transmier unit
• Connect output signal from Pulse generator to pulse input
of the FDA-301A unit
• Set 1 Hz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
• Set 10 MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
• Set 20 MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
Sine output ber test - transmier unit
• Connect the output of the Signal generator to the Sine input
of the transmier FDA-301A unit
• Connect the signal from the Sine Fiber output module of
the FDA-301A transmier to the input of the opcal power
meter
• Set 10 MHz frequency and amplitude 1 Vrms sine on the
Signal generator
• Verify that the opcal power level of the output is between
-15 and -18 dBm

10
Pulse output ber test - transmier unit
• Connect the output of the Pulse generator to the Pulse
input of the transmier FDA-301A unit
• Connect the signal from the Pulse Fiber output module of
the FDA-301A transmier to the input of the opcal power
meter
• Set 1Hz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V pulse signal on generator
• Verify that the opcal power level of the output is between
-15 and -18 dBm
• Set 10 MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V pulse signal on generator
• Verify that the opcal power level of the output is between
-15 and -18 dBm
Sine input ber test - receiver unit
• Connect the output of the Signal generator to the Sine input
of the transmier FDA-301A unit
• Connect the signal from the Sine Fiber output module of the
FDA-301A transmier to the sine ber input of the FDA-
301A receiver, using a short opcal cable (2-5 meters).
• Set 10MHz frequency and amplitude 1Vrms sine on the
Signal generator
• Verify that the sine signal diode on the FDA-301A receiver
unit goes green
Pulse input ber test - receiver unit
• Connect the output of the Pulse generator to the Pulse
input of the transmier FDA-301A unit
• Connect the signal from the Pulse Fiber output module of
the FDA-301A transmier to the pulse ber input of the
FDA-301A receiver, using a short opcal cable (2-5 meters).
• Set 1Hz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
• Set 10MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V on pulse generator
• Verify that pulse signal diode goes green
Sine output coax test - receiver unit
• Connect the output of the Signal generator to the Sine input
of the transmier FDA-301A unit
• Connect the signal from the Sine Fiber output module of the
FDA-301A transmier to the sine ber input of the FDA-
301A receiver, using a short opcal cable (2-5 meters).
• Connect signal from the sine coax output module of the
FDA-301A receiver to the input of the
• Oscilloscope (Use 50Ω terminaon)
• Set 10MHz frequency and amplitude 1Vrms sine signal on
signal generator
• Verify using oscilloscope that the amplitude is 1Vrms ±10%
(Vpp = 2.8V ±10%), and that the waveform of the signal is
not visibly distorted
Pulse output coax test - receiver unit
• Connect the Pulse generator output to the Pulse input of
the transmier FDA-301A unit
• Connect the signal from the Sine Fiber output module of the
FDA-301A transmier to the sine ber input of the FDA-
301A receiver, using a short opcal cable (2-5 meters).
• Connect the signal from the pulse coax output module of
the FDA-301A receiver to the input
• of the Oscilloscope (Use 50Ω terminaon)
• Connect the signal from the pulse coax output module of
the FDA-301A receiver to the input of CNT-90 (Set input
impedance 50Ω and DC)
• Set 1Hz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V pulse signal on the Pulse generator
• Verify using CNT-90 that the output frequency signal is 1Hz,
the High-level is 5V ±0.5V, and the Low-level is 0V ±0.5V.
• Verify using the oscilloscope that the waveform of the signal
is a pulse shape with overshoot/undershoot <20% of Vpp
• Set 10MHz frequency, duty cycle 50%, amplitude 5Vpp, Hi-
level 5V, Low-level 0V pulse signal on the Pulse generator
• Verify using CNT-90 that the output frequency signal is 10
MHz, the High-level is 5V ± 0.5V, and the Low-level is 0V
±0.5V.
• Verify using the oscilloscope that the waveform of the signal
is a pulse shape with overshoot/undershoot <20% of Vpp
PREVENTIVE
MAINTENANCE
No calibraon needed
No tradional yearly calibraon is needed for the FDA-301A.
There are no components inside aecng the specicaons
that are subject to ageing. However, we recommend a bi-yearly
performance check (Chapter 5) to verify that the unit is free from
HW faults.
Fan Replacement
The FDA-301A contains a fan with an expected life me of 5
years with connuous 24h/day operaon.
We recommend replacing the fan every 3 years to maintain
connuous high reliability. For part-me applicaons and low
ambient temperatures, an extended service interval is acceptable.
Fan replacement requires no special tools (screwdrivers only).
The part number of the replacement fan is 4031 105 02850.
Contact your Pendulum distributor for fan replacement

11
TECHNICAL
SPECIFICATIONS
Inputs
FiberopcinputsSine,PulseorE1
Fiber opcal connector: ST Wavelength: 820nm
Fiber type: Mulmode ber, 62.5/125µm or 50/125µm
Frequency for sine input: 10MHz (default); for other frequencies,
contact factory
ConneconberfromandFDA-301Aoutputtoanother
FDA-301A input: Max. opcal aenuaon: 6dB (including
ber and all connectors and splices) Max. distance: 2km
CoaxInputSineandPulse
Connector: BNC female
Frequency for sine input: 10 MHz (default); for other frequencies
contact factory Impedance: 50 Ohm nominal
Amplitude range: 0.2 Vrms to 2 Vrms (sine); -5V to +5V (pulse)
TimeofDay(ToD)
Input Connector: Mini Din 6 pins Female; RS232C electrical
levels accepted from -10V to +10V
Outputs
FiberopcoutputsSine,Pulse
Connectors: ST Wavelength: 820nm
Fiber type: Mulmode ber, 62.5/125μm or 50/125μm
CoaxOutputSine
Connectors: BNC female Impedance: 50 Ohm nominal
Output voltage: 1Vrms (sine) ±10% in 50 ohm
CoaxOutputPulse
Connectors: BNC female Impedance: 50 Ohm nominal
Output voltage: TTL-levels in 50 Ohm; low level ≤0.4 V; high
level ≥2.4 V
TimeofDay(ToD)Output
Connector: Mini Din 6 pins Female: Output voltage levels: Low
level is -5V nom.; High level is +5V nom.
Power Supply
ACpower
Input voltage range: 90 - 264VAC, 47 - 63Hz Power consumpon:
<40 W
DCpower-Opon
Input voltage range: 24 V ±10% Power consumpon: <40 W
Dimensions and Weight
Width: ½*19 inch (210mm) Height: 2U (90 mm)
Depth: 395 mm
Weight: approx. 3 kg (approx. 6 lb)
Environmental condions
Class: MIL-PRF-28800F, Class 3
Operang temperature: 0 to 50°C Storage temperature: -40 to
+70°C
Vibraon: Random and sinusoidal according to MIL-PRF-
28800F, Class 3 Shock: Half-sine 30G per MIL-PRF-28800F;
Bench handling
Transit drop test: Heavy-duty transport case and so carrying
case tested according to MIL-PRF- 28800F
Safety: EN 61010-1:2011, polluon degree 2, meas cat I, CE
EMC: EN 61326 :2013-6, increased test levels according to EN
61000-6-2:2008, Group 1, class B, CE
SERVICE
Sales and Service oce
For addional product informaon, customer support and
service, please contact your local Pendulum distributor, or
Pendulum Instruments directly at the following address:
USA:
Pendulum Instruments 50 Woodside Plaza # 642 Redwood City,
CA 94061 Vising address: as above
Delivery address: as above
Phone: [phone] (toll free)
Rest of the world:
Pendulum Instruments
ul. Lotnicza 37
80-298 Banino Poland
Vising address: as above
Delivery address: as above
Phone: [phone]
Fax: [phone]
Email: [email protected]om
Internet: www.pendulum-instruments.com

CONTACT PENDULUM INSTRUMENTS
SWEDEN
phone [phone]
[email protected]om
UNITED STATES
phone [phone]
us-o[email protected]om
POLAND
phone. [phone]
[email protected]om
CHINA
phone. [phone]
сhina-o[email protected]om
© Pendulum Instruments 2023
29.03.2023. FDA-301A. User Manual
Specicaons subject to change
or improvements without noce.
www.pendulum-instruments.com