Digital Signage – this weeks project

OK, so the prison TV project got cancelled as Liz Truss visited and said Bristol has a future (Gove wanted to shut all urban prisons) so they’re getting money thrown at them. The TV systems are to be upgraded to digital so no point in interfacing to the analogue system.

However they want 3 x digital signage installed to be administered centrally, but cannot be connected to the internet. Turns out they are quite happy to use Powerpoint to create content, turn it into MP4s and play back via VLC. That makes it easier.

Digital signage doesn’t need much firepower, you can even get Android boxes but they need either a cloud subscription or a bloody expensive local server licence. Also we want it to recover from power loss automatically and all sorts of management options. So a PC with Windows is the answer (I’ve had a real go at the Linux systems and they’re clunky, plus the customer knows Windows).

Normally you’d go for an mitx or NUC system and mount it near the TV, but in this case we have other considerations. So I decided we really needed a central location to house the PCs and use HDMI over Ethernet to get to the screens. There was some wall space high up in the staff key room, but the maximum size would be 6U so everything has to go in a H320mm x W550mm x D450mm enclosure. That’s 3 x PC and a 1U switch plus power distribution etc.

I worked out that across the 19″ width and 5U (8″) vertical height you could get 3 x small mitx or NUC boxes plus their power bricks, but it would be messy. Then there’s heat. The motherboards will be SoC Celeron types, <15 watt but passively cooled and a lot of the cases, especially the small ones, need decent airflow.

So after a chat with X-case I decided a 1U server case http://tinyurl.com/z8ua3zw could do the job. It has 3 x 40mm fans to provide airflow over the passive heatsink and board. The 3 units will only take up half the rack so there’s plenty of air volume left and it’s easier to keep the cables tidy.

As it turns out X-case sold out so I ended up with something very similar from Server Case http://tinyurl.com/gqnwh23 with a flex 250 watt PSU.

In there went an AS-Rock D1800B-ITX http://tinyurl.com/kyedur5 4GB of DDR3L, a Toshiba 120GB SSD and a £10 E-Bay W10 Pro with loads of cable ties. They are set up to run headless and automatically power back on in the event of power failure.

And here it is fully loaded. It’s currently being stress tested with it shut up as it will be on the wall and all 3 units at 100% CPU. After 6 hours the bottom unit is at Core 39C System 33C, the top Core 44C System 35C. So there isn’t going to be a heat problem.

The admin PC is a Skylake G4400 with 4GB DDR4 ram and a 240GB SSD. It has a £10 EBay W10 Pro and a £6 Ebay Office Pro Plus 2016 License. The media servers are controlled via TightVNC sessions.