Friday, January 29, 2010

Glitch Takes Eutelsat W2 Out of Action

I don't know if you noticed on Wednesday evening but Channel Five went off the air around eight-thirty. I was having breakfast with the Five engineers on Thursday and they mentioned that Eutelsat W2 carries their DTT distribution (so the feed to the various main-base Freeview transmitters around the UK). Arquiva must have quickly re-routed but it appears that as of today all Eutelsat have been able to do is move the bird to it's 'parking' orbit. It's quite an old satellite (launched in 1998) and was due to be decomissioned this year, but even loosing a few months must be costing a lot of money.

Monday, January 25, 2010

BT HomeHub madness!

The new BT Homehub (their aDSL WiFi router) comes in a very sleek black, but apart from that seems to be the same gadget they've been hawking for a couple of years now. Anyway - I was visiting with Sarah's folks this weekend when her Dad mentioned how slow his Windows XP machine had got (three year-old Dell which I routinely remote desktop into to check-out - make sure his AV is up to date and Windows updat has run etc.). So - I fired it up and it crawled for the first ten minutes and then perked up. A quick run of MSCONFIG.EXE revealed a few start-up services that were taking an age to launch and (hiding inside svchost.exe) they turned out to be FOUR (yes, count 'em!) processes that the BT Homehub2 CD installs.

Now then, this is an ethernet-connected router - the only software you need to configure the router is a web browser but this had piled on a load of crap-ware. It reminded me of the state the machine was in when Dell shipped it! I got rid of all the BT stuff and the machine was back to it's nippy self without any trouble from the router.

Tuesday, January 12, 2010

The importance of a consistent earth with technical mains

This is a paragraph from my standard Scope of Works document that goes to customers of build where I'm not responsible for the technical power;

Electrical requirements for all rooms part of the installation
We recommend an MCB-protected 16A mains feed terminated in a Commando connector. It is vital that the customer’s electrician runs the earths for the rooms back to the same earth bus-bar as the mains feeds to the bays thus creating a technical supply for all production/editing equipment. Failure to observe this request will cause mains hum on all video signal distribution around the new facility.

So we're quite explicit about the need for the need for a proper technical earth and what will probably happen if it's neglected. One of our recent builds has been having niggling problems with corrupt video captures and despite me having twice tested the physical layer performance of all the cabling (using the eye pattern on a Tek WFM7120) the attitude from the customer has been "…it must be the cabling or the routers you provided". After lots of haggling I was there recently and I measured a full 400mV of hum between the 'technical'(!) earth in the suites and the power distribution in the machine room. Given that an HD/SDi signal is only a volt I'm amazed they weren't seeing more corruption.
Now it's the inevitable "..why didn't you test for this and spot it earlier"? Perhaps there's a lesson here in not splitting the job up into many parts and using the cheapest contractor for each. If they'd been my electricians I'd have briefed them and made sure they ran proper tech earths - and I'd have made sure they tested them before handing over to the customer. That's why we'd have been a tad more expensive. As it is we'll no doubt wind up fixing this for free.

Saturday, January 09, 2010

Two more hardware standards Apple play fast 'n' loose with - DVI and Display Port

Another example of a customer splitting an equipment order into bits and not buying the monitors we recommended (saved a full fifty quid on each unit!) has combined with Apple's very poor implementation of 1920x1200 resolution to bit us in the backside.
The newest iteration of MacPro workstations ship with a display card that has a DVI and DisplayPort (with a DP->DVI breakout adapter). Aside from the problem of non-standard blanking as implemented in OS-X's drivers (see my blog entry about Kramer DVI routers) there is a very funny (but consistent effect) if you boot one of those computers with two monitors extended over fibre - you get one display at low-res and the procedure to get two monitors running at 1920x1200 is;

1. Boot the machine with a single monitor connected to the DVI port - increase resolution in increments to 1920x1200 @60hz
2. Reboot
3. Check the resolution sticks.
4. swap the monitor to the Display Port output
5. Reboot
6. Wind up the resolution as per 1. and if OS-X detects the extra monitor turn on display mirroring
7. Reboot
8. If both monitors come back up at 1920x1200 then turn off mirroring and ensure that both monitors are still at 1920x1200
9. Reboot
10. Make sure it's all sticking!

Compare this to the procedure for bringing up a PC-based Avid (running on an HP 8400/8600 workstation, nVidia card);

1. Set both displays for 1920x1200 @60hz

It is so clear that Apple assume you have the machine under your desk and you're using two of their monitors on the pre-made cables they supply. That's not how broadcast facilities are configured and if Apple wants to see FCP used more in film & TV they need to make their implementations of signal standards more robust.