A truck yard status screen works when it is a bay board, not a slideshow: one full-screen page on the PC that already feeds the TV, one tile per door, redrawn from the sheet the dispatcher saves. On a 75 inch, 1920 × 1080 set, 4 inch digits read past 80 ft and a 30 second reload keeps assignments current.
A 75-inch TV in a truck office exists to answer one question from the cab: which door? Slideshow signage fails at that job because every reassignment is a manual edit, and a word-processor page fails because drivers ignore dense text from the far end of the queue. The answer is a bay board: one full-screen page running on the Windows mini-PC that already feeds the TV, one large tile per door, green or red, redrawn from the sheet the dispatcher already saves. Size the letters by the standard letter-height rule and the board reads from the far end of the queue: a 75-inch, 1920 × 1080 set carries digits that read past 80 ft.
A bay board answers, a slideshow informs
Three facts decide the build.
The content changes when dispatch assigns doors, so the screen must redraw itself from data. Software that plays edited slides puts every change back on a person, which is the exact problem you are removing.
Drivers read from the cab, 20 to 30 ft out, often through a windshield in full sun. Letter height and tile color follow from that distance, not from what looks good on the office monitor.
There is one TV and one PC. A signage platform built to manage networks of players solves a problem you do not have, and it adds an account, a subscription and a failure point between the dispatcher's sheet and the screen.
So the decision lands before any product comparison: skip the slide apps and run a single data-driven page or script on the PC behind the TV. This is the same call behind any live factory data display: a playlist fills a wait, a board answers the question the driver came to ask.
Software options for the PC behind the TV
| Option | What drives the screen | Fits a dispatcher-edited bay board |
|---|---|---|
| Slide-based signage app | Playlists a person edits by hand | No: every change is a manual edit |
| Word-processor page or static image | Typed or exported by hand | No: dense text at that distance gets ignored |
| Dashboard or reporting tool, browser full screen | Its own database or the dispatch sheet | Yes, when assignments already live in a system |
| Single HTML page or short script | A file the dispatcher saves, or a small form | Yes: the simplest fit for one TV and one editor |
| Data-driven signage platform | Screen regions bound to live feeds | Built for airport-scale networks; too much for one board |
| Full LED sign board | The same page or a feed | Yes, when weather rules out a TV |
For one TV the single-page route wins. The dispatcher saves the assignment file to a fixed name, the page reloads it and redraws the tiles. The whole system is one PC, one browser and one text file, so no cloud account sits between the sheet and the screen, and a failed PC is rebuilt from a text editor. A reporting tool wins when the assignments already live in a database the yard maintains; then the board reads the same query the office reports read.
How tall the digits must be
The letter-height rule is the one road signs use: 30 ft of viewing distance per inch of capital letter height (FHWA planning figure). Work at 20 ft per inch when the reader is moving, viewing at an angle, or reading through glass, which describes a truck queue exactly. Spec the smallest text anyone needs from the farthest wait spot: divide that distance in feet by 20.
Screen fonts are set in pixels, and capitals run about 70 percent of a font's size in a typical face, so divide the target capital height by 0.7 to get the pixel size to set.
Fill the whole tile with color and put the word inside it: green OPEN, red HOLD, amber NEXT. Color alone loses a colorblind driver and washes out through a windshield; the word survives both.
The same distance-per-inch math sizes text on any screen, including text readability on small signage panels read from a few feet.
Example: 16 doors on a 75-inch TV
The TV is 75 in diagonal at 16:9, so the active area is 75 × 16 ÷ √(16² + 9²) = 65.4 in wide and 36.8 in tall. At 1920 × 1080 that gives 1920 ÷ 65.4 = 29.4 px per inch.
The worst wait spot sits 30 ft from the wall, read through glass, so the conservative rule sets the floor: 30 ÷ 20 = 1.5 in of capital height. Specify 4 in and the margin absorbs sun, angle and a dirty windshield.
Digit size: 4 × 29.4 ≈ 118 px of capital height, so set the number font at 118 ÷ 0.7 ≈ 165 px. The status word gets 2 in of capitals: 2 × 29.4 ≈ 59 px, an 85 px font, which the FHWA figure reads at 2 × 30 = 60 ft.
Layout: 16 doors map to 8 columns × 2 rows. Each tile is 1920 ÷ 8 = 240 px wide and 1080 ÷ 2 = 540 px tall. Two digits at 118 px capitals span about 130 px in a condensed face, roughly half the tile width, leaving room for the word below.
Check the result: 4 in capitals read at 4 × 20 = 80 ft by the conservative rule and 4 × 30 = 120 ft by the FHWA figure, against the farthest wait spot in the yard, so a driver parked along the fence at 60 ft still reads the board.
Past 16 doors, shrink to 3 in capitals: 3 × 29.4 ≈ 88 px, an 88 ÷ 0.7 ≈ 125 px font, in 10 columns of 192 px each. That still reads at 3 × 20 = 60 ft.
Keep the board honest through the shift
Reload the data every 30 seconds. A driver in line waits longer than that, so the board never looks stale; 60 seconds is the slowest cycle worth running. If dispatch types into a form instead of saving a file, push the change on submit and keep the 30-second reload as the net underneath.
Decide the PC's boot behavior up front: auto log-in, start the browser or script full screen at boot, set sleep and screensaver so the display never blanks. After a power cut the board returns on its own, which matters on a dock where somebody resets a breaker and walks away.
Keep the dispatcher's edit path as it is: save the same sheet to a fixed file name in a shared folder, and the page reads that file. If assignments live in a database, the page reads the same query the office reports use.
Pick an LCD TV. A fixed layout can leave a faint temporary imprint on an LCD panel, and it clears; static content on an OLED panel burns in for good, so an OLED set is the wrong screen for a board like this.
If the set hangs high on the dock wall, hang it on a bracket rated for its size and weight. A 75-inch panel is heavy, and it lands on concrete.
When a 75-inch TV is the wrong screen
An unroofed yard needs an LED sign board, not a consumer TV: sun, weather and distance all move that way, and the same bay-board content can feed it. The sizing math is in choosing a large LED sign board for a shop floor.
If drivers must do more than read, such as checking in a trailer or confirming a door, the job turns interactive and the hardware question changes with it. That is the split in status display or operator screen, and touch, mounting and enclosure follow from it.
For a second, smaller copy in the dispatch office, where nobody reads from across the room, a panel-mount Android display that plays exported images from USB covers the want; we build those in our panel-mount display range. Export the board to an image, load it onto the USB stick, and accept that the office copy lags the yard board by however often you re-export.
The decision and the spec to hand off
Recommendation: for one 75-inch TV read from the cab through a windshield, run a single full-screen page on the TV's Windows PC: one tile per door in 8 columns × 2 rows, 165 px digits with 85 px status words as sized above, tile color always paired with a word, and a data reload every 30 seconds. Move to an LED board when the yard has no roof over the reading spot; move to an interactive screen when drivers must touch it.
Hand the builder the rest as a spec:
- Door count and the farthest wait distance, in feet.
- Whether glass, sun or an angle sits in the sight line.
- The dispatcher's edit method: a saved file, a small form, or a database query.
- Refresh cycle: 30 seconds.
- Boot behavior: auto log-in, full-screen start, sleep off.
- TV type: LCD, and the bracket rating if it hangs high.
- Tile design: capital heights and pixel sizes from the example.
Questions
Will a fixed layout burn itself into the TV?
On a standard LCD TV, the worst a fixed layout usually causes is a faint temporary imprint. Running a full white field or a moving slideshow for a while clears it. OLED panels are the real risk: weeks of static tiles can burn in for good, which is why the spec calls for LCD. A board that rotates a header image or a logo now and then mostly avoids the question.
Does the board need an internet connection?
No. The page, the browser and the dispatcher's file all live on the yard PC or its local network, so assignments keep flowing with the internet down. You only need outside connectivity if you want to edit the board from home or read the sheet out of a cloud service.
Can drivers check the board on a phone?
Yes, if the board is served as a small web page on the yard network: any phone browser can open its address and read the same tiles wherever coverage reaches. Keep the phone layout to numbers and words, and keep phone use to the cab or the gate house; the board exists so nobody has to walk the line to ask.
Planning information, not legal or engineering advice. Rules differ by place: check codes and permits with your local authority and your licensed trades.