SHORTENING TRUCK ROLLS USING PROPER PREPARATION
- Published , by Tom Devine
Truck rolls are nearly impossible to avoid, and time spent at these jobs sites means money out of your pocket. Luckily, equipping your technicians with the proper tools can ensure quicker diagnoses and less time spent revisiting jobs.
Infrastructure
Faulty infrastructure can be the death of one or more runs in a system. Proper infrastructure equipment includes:
- Minimum 2M HDMI Cables (18Gbps Compliant)
- Minimum 2M Cat6 Patch Cables
- Standard RJ45 Category Ends (No Pullthrough or EZ ends)
- Replacement Power Supplies
The HDMI specification for cables is 2-10 meters in length. Cables, whether shorter or longer than this specification, can suffer from voltage irregularities, attenuation, sync issues, and resolution limitations. By having various lengths of cables, you can instantly replace bad cable runs and restock when the truck returns.
Moving on to patch cables, a minimum of 2 meters of Cat6 is recommended. Patch cables following this rule provide a stable, good length for testing extender sets in isolated settings and also can double for running LAN in IP control situations. Standard RJ45 ends provide better stability of both connection and data transfer. Pullthrough and EZ Ends can have inconsistencies in their terminations which can cause shortages and destabilize signals (especially at higher resolutions). Lastly, stock up on common power supplies. Once again these allow you to not only isolate units and gives the ability to instantly switch a bad power supply. Infrastructure can be kept flowing smoothly by diagnosing and fixing the easy problems in one roll.
Hardware
Sources, switches, and displays can be considered the heart of the installation. Some units can underperform or need specific things to work properly (such as color space and resolution, contained in EDID). Proper field fixes for signal cleanup should include:
- Unit with EDID Management
- A 1x2 Distribution Amp
- A Scaler
- Audio Downmixer
Cable boxes are just one of the various sources that tend to underperform in distributed systems. Cable boxes use HDCP (High-Bandwidth Digital Content Protection) to prevent piracy. HDCP contains keys (permission to pass the sources HDCP content) and can only give out a certain number of keys. HDCP issues can arise and appear as intermittent video or no signal at all. Distribution amps (like the AC-DA12-AUHD-GEN2), have a repeater inside the unit and allows for a reissue of HDCP keys. This is useful in systems that include extenders and multiple jumps as a key must be issued to each new HDMI connection.
Now, not all blame can be pushed onto cable boxes as some newer displays have issues handling certain types of signals. More advanced displays have been found to struggle with interlaced signals (i.e. 1080i), 24 and 48Hz refresh rates, and needing device specific EDIDs. These struggles can be solved using a scaler. Scalers (such as the AC-SC2-AUHD-GEN2) can provide interlaced to progressive framerate conversion and increased framerate (60Hz), as well as manage EDID. The combination of these functions help sources fulfill the necessary signal needed to work properly with the display.
Finally, audio products such as soundbars or older AVR’s may run into issues with higher resolutions, HDR, and high bitrate audio formats. An Audio Downmixer (similar to the AC-AVDM-AUHD) can take these higher bitrate formats and downmix them to 2 channel PCM. As for higher resolutions and HDR, the AVDM offers a scalable port that not only downscales to 1080p but removes the HDR metadata, allowing audio devices that are not 4k HDR capable to accept the signal.
External Devices
Let’s consider external devices that are used to relay information such as HDMI testers or USB cables. Proper external tools should include:
- Micro USB
- Mini USB
- RS232 to USB
- Windows PC
- HDMI Cable Tester
The ability to connect to a unit in the field is a necessity. Micro, Mini, or RS232 to USB are all common connection types to communicate to with units. Combined with a Windows PC (compatible with most units), more feedback than ever can be obtained. Being able to connect to these devices can assist in firmware updates as well as accessing specific commands that cannot always be accessed via button press or in a GUI.
Lastly a good HDMI Tester (we recommend the Fox & Hound) can help diagnose problems in a system. A good tester should come with the ability to send and accept HDMI signals and allow you to generate an 18Gbps signal, test HDCP, and read EDID. In addition, having an analyzer that allows you to read incoming signals can be very helpful. Analyzers also work as a mobile test monitor and allow for movement along the runs to help pinpoint where failures are occurring. These tools can drastically decrease time and truck rolls by decreasing guess work.
Time is money and each and every truck roll means time. By properly preparing a truck for a job, labor costs and guesswork can be massively reduced.
