Highly precise sync generation to ensure seamless Hybrid IP/SDI operations

Leader’s LT4670 Sync Pulse Generator is designed to meet the demands of modern hybrid SDI/IP networks. The LT4670 supports both PTP (IEEE 1588-2008) for IP-based environments and traditional black burst and tri-level sync for SDI. This ensures seamless timing accuracy between legacy and nextgeneration workflows. Whether you are synchronizing cameras, routers, switchers, or production servers, the LT4670 provides a rock-solid reference to keep your entire operation in sync.

Unmatched Timing Precision

With a high-stability oscillator, the LT4670 delivers precise synchronization, eliminating drift and ensuring reliable timing across SDI and IP infrastructures. The LT4670 can also act as a PTP Client, receiving PTP from a broadcaster’s IT Grandmaster Clock, ensuring that both the IT system and their ST 2110 infrastructures are synchronized. Even in environments with heavy network traffic, the LT4670 maintains microsecondlevel accuracy, ensuring no disruption in signal integrity. For broadcasters handling 4K, 8K, and HDR workflows, this level of precision is a vital, reducing the risk of timing discrepancies that could impact high-resolution productions.

Scalable for the Future

Whether you’re operating a small studio or a large broadcast facility, the LT4670 scales to meet your needs. It is designed for future-proof flexibility, allowing broadcasters to gradually transition towards full IP workflows without disrupting operations. As new standards emerge and industry expectations evolve, having a scalable SPG like the LT4670 ensures that your investment remains viable for years to come.

Advanced Test & Monitoring Features

The LT4670 includes SMPTE ST 2059-2 compliance, ensuring interoperability with other PTP devices in your network. It also provides various test signals for troubleshooting and validation, making it an essential tool for engineers. Whether you need to verify timing accuracy, check for synchronization issues, or diagnose potential faults, the LT4670 offers the tools necessary for quick and efficient problem-solving. These features make it not just a sync generator, but a comprehensive solution for managing synchronization across a hybrid broadcast network.

Precise time synchronization is critical for all applications in broadcast. Blackburst/Tri-Level Sync, AES, Timecode, Test Patterns and Precision Time Protocol (PTP) are widely used method to distribute accurate time across broadcast facilities, ensuring frame-accurate video switching and synchronization.

The simplest way to ensure that your Blackburst /Tri-Level Sync, AES, Timecode, Test Patterns and PTP remain synchronised is by having all reference sources generated from the same oscillator in your Sync Pulse Generator and that unit is locked to a GPS reference, like the Leader LT4670.

That way, if the Sync Pulse Generator loses its GPS reference, both BB/TLS and PTP references will use the Sync Pulse Generators ‘signal oven controlled internal’ oscillator and go into ‘Stay-in-Sync’ mode.

When the GPS reference returns, a ‘slow-lock’ function is available to eliminate the shock that occurs when genlock is performed again based on ‘Stay-in-Sync’. When SPGs lose their GPS reference, how they recover and maintain time synchronization can significantly impact broadcast system stability. One of the key techniques to mitigate timing disruptions in the LT4670 is slow syncing – a method of gradually adjusting the clock rather than making abrupt corrections.

Slow syncing Blackburst/Tri-Level Sync, AES, Timecode, Test Patterns and Precision Time Protocol (PTP) during GPS reference loss is a crucial technique for maintaining broadcast network stability and ensuring reliable time distribution. By gradually steering the clock and avoiding abrupt corrections, broadcasters can prevent video and audio disruptions, improve synchronization accuracy, and enhance overall system resilience. Implementing best practices for slow syncing can help safeguard live broadcasts, post-production workflows, and seamless playout operations even in challenging conditions.

Implementing Slow Syncing in Broadcast PTP Systems

To effectively implement slow syncing in a broadcast facility, the Leader LT4670 Sync Pulse Generator utilises the following best practices:

• Use High-Quality Oscillators: A stable oscillator with low drift ensures that the system can maintain accuracy when GPS is unavailable.
• Enable Holdover Mode: Configure the PTP grandmaster to enter holdover mode when GPS is lost, allowing it to rely on its internal timing source.
• Configure Slow Syncing Algorithms: Adjust PTP settings to apply gradual frequency adjustments instead of immediate jumps.
• Monitor and Log Timing Performance: Regularly check synchronization accuracy and adjust settings as needed to optimize performance.

Genlock

Supports NTSC/PAL black burst signals and HDTV tri-level sync signals for synchronizing output signals. Additionally, it accommodates NTSC/PAL black burst signals with field reference pulse and NTSC black burst signals with 10-field ID. A 10 MHz CW lock is supported as standard. Options are also available for PTP and GNSS synchronization.

Stay-in-Sync & Slow Lock

The LT4670 is designed for maximum reliability in mission-critical environments. If the genlock input signal becomes unstable or is lost, the stay-in-sync function maintains the current synchronization state to avoid signal interruptions. Once a stable reference returns, the slow-lock function re-establishes synchronization gradually, minimizing timing disruptions and visual artifacts. These features work with various reference sources, including black burst (BB), tri-level sync, 10 MHz CW, GNSS (with SER01), and PTP (with SER03), ensuring flexible and robust system integration.

Six independant analog video sync signal outputs

Designed for high versatility, the LT4670 provides six analog video sync outputs that operate independently. Each output can be configured separately, with adjustable phase offsets to meet the unique synchronization demands of multi-device systems. This enables precise alignment of signal timing across various equipment, from cameras to routers and monitors. All outputs support black burst (NTSC/PAL) and tri-level sync formats, making them suitable for a wide range of applications in SD, HD, and UHD workflows.

Synchronous control between devices

In systems requiring redundancy, the L-SYNC function allows the LT4670 to synchronize its internal clock with another unit using the same analog video sync signal. This ensures that a backup unit remains perfectly in sync with the primary unit, allowing for a seamless switchover in the event of failure. Synchronization extends across multiple outputs, including PTP (SER03), LTC, black burst with VITC, SDI ATC (SER02/SER04), AES/EBU, and NTP, making L-SYNC a key component of a fail-safe timing architecture.

CW/1PPS Output & LTC I/O

A selectable CW/1PPS output is available as well as LTC can output three independent systems for each input. The outputs can be set for frame rate and offset time relative to the reference time, respectively.

World Clock

To ensure accurate audio-video synchronization, the LT4670 offers a dedicated 48 kHz word clock output. This output is aligned with the reference video signal, enabling stable timing for digital audio equipment such as mixers, recorders, and DAWs. By maintaining synchronous timing between audio and video systems, the word clock output is a key component in preventing audio drift and ensuring seamless post-production and live broadcasting operations.

User Preset and Memory Functions

The LT4670 streamlines configuration with memory and preset features that enhance operational flexibility. The unit retains its last-used settings even after power cycling, reducing setup time. Users can store up to 10 custom presets that capture complete configuration states, allowing fast recall of complex settings for different production scenarios. This functionality is especially valuable in environments where system profiles change frequently, such as rental houses, OB trucks, or multi-studio facilities.

Redundant power supply and non-stop power supply and fan replacement

Engineered for high availability, the LT4670 supports an optional redundant power supply module (LT4670-SER11). This ensures continuous operation in the event of a power failure. Both the power supply and cooling fans are hot-swappable, allowing for maintenance or replacement without interrupting service. This feature is ideal for 24/7 broadcast and production facilities where downtime is not an option, providing peace of mind and uninterrupted performance.

Realtime Clock

The realtime clock is backed up by a battery. There is no need to reset the date and time when the power is turned on and off.

Ethernet

The instrument can be controlled via HTTPS/HTTP and a REST-API as well as with SNMP. It can connect to an NTP server to set the internal clock time or operate as an NTP server.

LT4670-SER01 (GNSS)

By connecting a GNSS antenna, each signal can be generated and output locked to the frequency and time obtained from GPS, GLONASS, GALILEO and BDS.
A hold-over function is provided to hold the phase and frequency of the output signal upon loss of GNSS signals.

LT4670-SER02 (SDI)

Triple-rate SDI support
3G-SDI (Level A, Level B), HD-SDI and SD-SDI. 2 independent SDI signal output terminals are provided, and the pattern and phase can be set for each.
In addition, two SER02s can be installed to output up to four independent SDI signals. Furthermore, by adding the 4K option (SER21), 4K 3G-Quad Link is supported.

User pattern output
In addition to built-in patterns such as color bars, SD and HD (2K) user patterns can be output.
ID Character Superimposition
ID characters can be superimposed at any position on the screen. In addition, horizontal scrolling and blinking display can be used to confirm active status.

Logo Superimposition
24-bit full color bitmap data with a size of 640 (dots) x 480 (lines) (VGA size) can be superimposed as a logo mark at an arbitrary location or the screen.

Safety Area Marker
Safety area markers of 90% and 80% can be superimposed on the screen, as well as 4:3 aspect markers for 3G-SDI and HD-SDI.

Pattern Scroll
Scrolls the pattern in 8 directions. The speed of movement can also be varied.

Moving Box
Boxes that move on the screen can be superimposed. Color, size and speed of movement can be varied.

Circle
90%, 80% and 70% circles can be superimposed on the screen. Brightness can be switched and blinked.

Time Code
Time code can be superimposed at any position on the screen. Font size and brightness can be changed.

Embedded Audio
16 channels (4 channels x 4 groups) of embedded audio can be added. Frequency, level etc can be set for each channel.

Lip-Sync Pattern
Outputs a lip-sync pattern with synchronized video and audio. By using a waveform monitor equipped with a lip-sync measurement function, such as our LV5600W, it is possible to measure the discrepancy between video and audio on SDI signal transmission..

LT4670-SER03 (PTP)

PTP Leader
Precision Time Protocol as specified in IEEE 1588-2008 and operates as a PTP grandmaster. Profiles supported are SMPTE 2059, AES67 and General; the PTP time source is obtained from the built-in clock, NTP server, GNSS, VITS or LTC.

PTP Follower
If there is a higher PTP grandmaster on the system, it can act as a PTP follower and also act as a PTP leader to lower devices.

Two independent PTP ports
Two PTP engines are installed, each of which can be used as an independent grandmaster to build a PTP system. Two systems can be used in a follower configuration. The leader can be selected by the user or automatically. Additionally, can be configured with one follower and the other as leader.

10GbE Support
Compatible with 10GbE SFP+ modules (sold separately)

Local PTP
With the Genlock Function genlocked to an analog video sync signal or HDTV tri-level sync signal, time information can be acquired from an external time source

LT4670-SER04 (25G IP 12G TSG)

25G IP Signal Generation
Test pattern signal generation function for IP, supporting SMPTE ST 2110-21/30/31/40 for IP transmission standards, and capable of generating 2K and 4K (3840 x 2160) test patterns for video signals.

12G-SDI (4K) Support
Supports 12G-SDI, 3G-SDI (Level A, Level B), HD-SDI and SD-SDI. 4 independent SDI signal output terminals are provided, each with its own pattern and phase settings.

User Pattern Output
In addition to built-in patterns such as color bars, arbitrary patterns can be output.

LT4670-SER11 (POWER)

Redundant Power Supply
For added security of operation, the LT4670 supports dual power supplies by adding LT4670-SER11(POWER). In the event of a power unit failure, an alarm is displayed on the panel of the main unit, and an alarm can also be output via SNMP.