Thursday, June 19, 2014

The Degree Show

The Degree show 2014 has began. It started on a really stressful way. At one hour to go we could not get the audio to work on both of the encoders as well as been pushed in last minute to be the only presentation operator. This was putting a lot of pressure on the team. We had been working hard for the past 3 moths to possibly lose everything on the show day but we could not permit that. We had to step up and we did. I leant as quick as I could the play out system while Aidan with the help of Ryan and Lee were trying to fix the audio problem as we as trying to make 5.1 work. I needed to play something before our live at 1PM so they could detect the audio and fix the problem. At 15min to go manage to make everything work.

Another problem was me being drafted in as only presentation operator I wasn't fully aware of what had been QC'd so it happened that I played something that wasn't QC'd and it had illegal colours, which both Martyn and Martin made me noticed. Luckily we had a ligalizer with us so we made our TX go through that and it fixed it.


Simon and engineer form Arqiva came to test our signal and he noticed that we were outputting at a really low wattage. This was because while we were testing the system we did not save the settings so when we turn the transmitter back on it had the old setting. So we were able to put it back to 5 watts.

The transmission came to an end on wednesday. Through out this experience I've leant a lot, experienced a lot of feelings and faced many difficulties but I am really satisfied with the outcome even though we faced many problems we managed to deliver the show and add something new lie 5.1 dolby digital transmission. what I can say is that time management is important for projects like this and I wish I could realised this before it was too late but is something I have on board now. Planning as well is essential, with many redundancy plan as you can I've learnt that they can never be many. At the end it brought out of me confidence, something I was lacking a lot. It was a great experience and I'm grateful for it.

Receiving U400 and HD encoder and building full chain

In the last week before the degree show I received the antenna and the HD encoder to complete the transmission chain. Stephen also came down again to help us finalise it. Aidan created a transport stream to check if it's was working and everything was going trough fine. We played to footage trough our TX the image were showing on the SD but it had jitter and lip sync problems and the HD was given problem as well. While I was trying to fix it Stephen advised me to put the PCR (program clock reference) PIDs sam as the video PIDs and it worked at that point our full transmission was working perfectly.


With the help of Evan we mounted the antenna on the roof.

Receiving transmitter, receiver and Allocation of channels form Digital UK

A couple of days a go I received an email from Stephen telling me that the transmitter and receiver were on their way to Ravensbourne, those came today. This is a good news we will finally have a complete basic transmission rack. As soon as those came I added them with the rest of the kit in CAR.

Stephen also confirmed to us that our LCN's have been approved. Digital UK has allocated us channel 792(HD) and 793(SD) for our services.

Reflection:

From a few weeks to go things are getting a bit smoother, me and Aidan have been working to make our excel sheet work as well as building the full rack. We are still far away from what we want to achieve but it's looking good. 

Installing the SIM

This week we received the Service Information Manager (SIM) form Arqiva. The purpose  of the SIM will be to insert our SI data on to the stream before modulation. The SIM has a web gui which mean we are able to access it with our laptops and see our SI information. We've been having major problem with the Excel macros and struggling to make a working transport  stream. The excel seems not to generate a PAT table. We've been stuck with this for a little while now and is given us issues we need to solve as soon as possible with 3weeks to go.

With 3weeks to go some kit has started coming in which, is good but is getting tight and for now we are no point close to what we want to achieve this year (subtitles and 5.1 audio) my team needs a meeting to plan the weeks ahead because is going to be really stressful with exams and course work in the mist of it.

Meeting with Screen System

After meeting screen system at BVE we called them and invited to come to Ravensbourne to give us more details on how to create and transmit subtitles. They kindly agreed that they will give us the subtitle kit as a permanent loan not just for us but also for the next engineers. The visit gave us more understanding on how subtitles work on DVB-T. Now will be waiting to receive the kit and get our hands on it and see what we can do.

This is the U400, the kit screen has kindly agreed to loan us.

Wednesday, June 18, 2014

Meeting with Stephen Foden

Stephen Foden form Arqiva came to visit Ravensbourne. This visti was mainly focused on the trasport stream and SI specification for DBV-T. We even touched on the future of FreeView in UK. After that we actually tried to generate a transport stream that would contain all the SI table needed for DVB-T. We had some problems we the Excel sheet that stephen gave to Ben last year to use as EPG. On the other hand the meeting with steve has helped to give us more knowledge on the matter.

We spent time on the MUX as well trying to understand its configuration. We manage to generate different services and add PID directly on the Mux.