SDI FC-250-10P User manual

FC-250-10P
LOW NOISE FREQUENCY CONVERTER
OPERATING MANUAL
SPECTRADYNAMICS, INC • 1849 Cherry St. Unit 2 • Louisville, CO 80027
Phone: [phone] • Fax: [phone]
www.spectradynamics.com
SPECTRADYNAMICS, INC

FC-250-10P Low Noise Frequency Converter Operating Manual
Copyright © 2021 SpectraDynamics, Inc. All rights reserved.
FC-250-10P/MD-FA

Contents
1.0 Introduction …………………………………………………………………….... 1
2.0 Safety and preparation for use ………………………………..……….…….. 2
2.1 Electrical ……………….…………………………………………….……. 2
2.2 Instrument ……..…………….………………………………….….…….. 3
3.0 Front panel description …….…………………………………………….…… 4
4.0 Back panel description ………………………………………………….……. 5
5.0 Installation ……………………………………………………………….…….. 6
6.0 Operation ……………………………………………………………………… 7
7.0 Troubleshooting ………………………………………………………………. 8
8.0 Specifications …………………………………………………………………. 9
9.0 Warranty and service ………………………………………………………… 11

1.0 Introduction
Page 1
The FC-250-10P is a Low Noise Frequency Converter for Optical to RF Signals. This
instrument can be used to generate low noise 10 MHz, 100 MHz and 1PPS signals that
derive their phase noise and stability from an external 800-1650 nm pulsed optical signal
with a repetition rate of 250 MHz. A high speed photodiode is used to convert the optical
signal into RF and a proprietary synthesizer is used to generate 10 MHz, 100 MHz and 1
PPS outputs.
This instrument is designed to operate with a 100 to 240 VAC, 47 to 63 Hz power source
and is housed in a 2U, half rack enclosure.

2.0 Safety and Preparation for Use
Page 2
The FC-250-10P was designed for indoor use only and is not intended for operation
outdoors or in a wet environment.
Inspect the instrument and power cords for damage before first use.
2.1 Electrical Safety and Preparation for Use
Voltages capable of causing injury or death are present in this instrument. Use extreme
caution whenever the instrument cover is removed.
Line Voltage
This instrument is designed to operate with a 100 to 240 VAC, 47 to 63 Hz power source.
Fuse
A 2.0 Ampere 250 V 5X10 mm slow-blow fuse is used for 100 to 240 VAC operation.
Only replace fuse with the same type and specifications.
AC Power
The instrument has a detachable three wire power cord for connection to a grounded AC
power source. The enclosure of the unit is directly connected to the outlet ground to
protect against electrical shock. Always use an outlet with a protective ground and do not
disable this safety mechanism. Detaching the AC power cord is the only option of
disconnecting the unit from the AC mains supply. Make sure you have access to the rear
panel or provide an external accessible AC disconnect means for the FC-250-10P.

2.0 Safety and Preparation for Use
Page 3
2.1 Instrument safety and preparation for use
The FC-250-10P contains a sensitive photodiode. The steps below must be followed to
ensure reliable operation.
1. Apply AC power to the FC-250-10P.
2. Apply optical power.
3. If there is no RF output after connecting the optical input please reset the device by
turning the AC power switch to the off position for 5 seconds and then turning the switch to
the on position.
Absolute Maximum Ratings
Optical input power: +10 mW Maximum
Reverse power into an output: +20 dBm Maximum
DC Voltage at RF Outputs: 50 VDC Maximum
Storage Temperature: -10 to +75 ºC
Operation Environment: 0 to +50 ºC

3.0 Front Panel Description
Page 4
ON Power LED
The Power LED turns on when AC power is applied to unit.
800 - 1650 nm Connector
Apply a 800 to 1650 nm pulsed optical signal with a repetition rate of 250 MHz to this
connector.
OUTPUTS:
10 MHz
A 10 MHz signal with 12 +/- 2 dBm will be available at the connector labeled 10 MHz.
100 MHz
A 100 MHz signal with 7 +/- 2 dBm will be available at the connector labeled 100 MHz.
1 PPS
This output provides a TTL, 1 pulse per second signal. The pulse width will be 8 ns long for
an unsynchronized signal and 512 us for a synchronized signal.
REF INPUTS:
SYNC
On initial power up, the sync enable port should be held high to synchronize the internal
PPS generator. The synchronization will happen on the next rising edge of the 1 PPS
INPUT connector. If instead, the SYNC ENABLE port is held low, no synchronization will
happen and the unit will immediately start its internal PPS generator. The internal PPS
generator may be synchronized at any time by holding the SYNC ENABLE port high for a
minimum of 300ms.
1 PPS
Receives a 1PPS synchronization input. The 1PPS signal must conform to TTL
specifications.

4.0 Back Panel Description
Page 5
AC Power
The FC-250-10P is configured to operate on 100 to 240 VAC.

5.0 Installation
Page 6
This instrument is designed to operate with a 100 to 240 VAC, 47 to 63 Hz power source
and is housed in a 2U, half rack enclosure.
Connecting Power
The FC-250-10P ships with a standard North American, European, or Chinese IEC power
cord.
Locate the AC POWER entry module on the rear of the enclosure and connect the power
cord.

6.0 Operation
Page 7
Plug the power cord into an appropriate AC power outlet.
Once AC power is supplied to the FC-250-10P the LED on the front panel labeled POWER
will turn on.
After the AC power has been applied, an optical signal may be applied to the input fiber
optic connector. Care must be observed when using the FC-250-10P, optical power
greater than 10 mW will damage the internal components.
Once the optical signal is applied to the FC-250-10P, a high speed photodiode will convert
the optical signal into RF signals that are processed to generate 10 MHz, 100 MHz and
1PPS outputs. All outputs are available at the corresponding SMA connectors located on
the front panel. If an optical signal is applied to the device and there is no RF signal
output , please reset the instrument by turing of the unit for 5 seconds and then turning it
back on.
The 1 PPS output will not be available unless the SYNC input is held low or terminated into
50 ohms.
To synchronize the 1PPS signal to an external 1PPS signal, first apply the external 1PPS
signal to the port labeled 1PPS IN and then hold the SYNC ENABLE port high for a
minimum of 300 ms. The synchronized 1PPS signal will then be available at the 1PPS
OUTPUT port. A synchronized signal will have a 512 us pulse width and an
unsynchronized signal will have a 8 ns pulse width.

7.0 Troubleshooting
Page 8
Do not attempt to service or adjust the instrument unless another person, capable of
providing first aid or resuscitation, is present.
If there are problems that cannot be resolved by the troubleshooting steps below please con-
tact technical support.
Technical Support
Tel: [phone] , Fax: [phone]
[e-mail], www.spectradynamics.com
AC Power LED does not turn on.
Disconnect the power cord and remove the top cover. Check the main AC power fuse and
power cord. If the fuse is blown replace with same type and rating. Please contact SDI if the
fuse blows again or if the event that caused the fuse to blow is not known.
No RF or PPS Output Signals.
Verify that the provided optical signal is within specifications, 800 to 1650 nm pulsed signal
with a repetition rate of 250 MHz. Reset the device by turning the power off for 5 seconds
and then turning the device back on.

8.0 Specifications
Page 9
PARAMETER CONDITIONS MIN TYP MAX UNITS
10 MHz output level +12 +13 +14 dBm
100 MHz output level +6 +7 +9 dBm
Stability of 10 MHz Output Pair Measurement 1 e-14 2 e-14 -
Temperature Stability @10 MHz, 20-50 °C
@100MHz, 20-50 °C
- 0.5
1
1
2
ps/K
Residual Phase Noise
10 MHz Output
1 Hz
10 Hz
100 Hz
1 kHz
>10 kHz
-
-
-
-
-
-142
-152
-162
-167
-169
-138
-150
-160
-165
-167
dBc/Hz
Frequency Stability
10 MHz Output
1
10
100
1000
10000
-
-
-
-
-
2.8 E-14
3.6 E-15
5 E-16
1 E-16
4 E-17
3 E-14
5 E-15
1 E-15
5 E-15
1 E-16
Residual Phase Noise
of the 100 MHz Output
1 Hz
10 Hz
100 Hz
1 kHz
>10 kHz
-
-
-
-
-
-127
-137
-147
-152
-155
-125
-135
-145
-150
-155
dBc/Hz
Frequency Stability
100 MHz Output
1
10
100
1000
10000
-
-
-
-
-
5 E-15
1 E-15
5 E-16
7 E-17
1 E-17
3 E-14
5 E-15
5 E-16
3 E-16
1 E-16
Harmonic Distortion - -35 -30 dBc
1 PPS output level 50 ohm load 2.5 3.9 5 V
1 PPS External Sync Error - < 5 10 ns

8.0 Specifications
Page 10
Other Specifications
Rackmount chassis 2U H, 8.37” W, 10” D (88.1 X 212.6 X 254 mm)
Unit weight 5 lb (2.3 kg)
AC Input Voltage Range 100 to 240 VAC, 22 W, 47 to 63 Hz
Storage temperature -10 to +75 ºC
Operation environment 0 to +50 ºC
Humidity 5% to 95% Non-condensing

9.0 Warranty and Service
Page 11
Warranty
The FC-250-10P is warranted to be free of defects under normal operating conditions, as
specified, for one year from date of original shipment from SpectraDynamics, Inc. (SDI).
SDI’s obligation and liability under this warranty is expressly limited to repairing or
replacing, at SDI’s option, any product not meeting the said specifications. This warranty
shall be in effect for one (1) year from the date a FC-250-10P is sold by SDI. SDI makes
no other warranty, express or implied, and makes no warranty of the fitness for any
particular purpose. SDI’s obligation under this warranty shall not include any transportation
charges or costs of installation or any liability for direct, indirect, or consequential
damages or delay. Any improper use, operation beyond capacity, substitution of parts not
approved by SDI, or any alteration or repair by others in such manner as in SDI’s
reasonable judgement affects the product materially and adversely shall void this warranty.
No employee or representative of SDI is authorized to change this warranty in any way or
grant any other warranty.
Service
Do not attempt to service or adjust the instrument unless another person, capable of
providing first aid or resuscitation, is present. Please remember that any alteration or repair
may void the warranty. Contact SDI with any questions or to request an RMA if a repair is
needed.
SpectraDynamics, Inc.
1849 Cherry Street Unit 2.
Louisville, CO 80027, USA
Tel: [phone]
Fax: [phone]
[e-mail]
www.spectradynamics.com