777-300ER GMCS at night

[bauduin_alex]

Good day,
I have a heap of trouble with the quality of the picture at night with the GMCS. With the cam light on and if I have the DU brightness to max the picture is very bad, like from a very old VHS tape. If I turn cam light off it is even worse. It is bad on all DU's I've even swapped ND PFD to try it out.

Already looked for videos on the web but all very bad quality so I can t even assess the quality of the video on DU.

So if one of you is going tonite or soon up there on a night flight, try to make a shot of the DU, Light cam on and full bright on the DU. And even better is the picture can be taken on a taxiway, safety permitting.

Or if you cannot take a picture give me some feedback about what you've observed with this settings.

Alex, from downunder.
Thanks.

[halas]

It seems a bit hit and miss with picture quality.

Here in EK some appear as HD quality, whilst others are less than useless, even on some of the newer deliveries. Go figure?

halas

[nitpicker330]

This was one of my biggest complaints when I was on the ER.
The quality was rubbish most of the time, JFK at night was a place the ER really needed it to work but.........

In the day it was over exposed and in the dark it was under exposed!!

You'd think a 250+ million dollar aircraft could be fitted with a decent camera just like most new cars?????

I wrote up the defect many times only for Engineering to clear it saying "appears normal"

It'll take a Taxi incident for the Airlines to complain to Boeing.....( they'll still blame the crew however )

[bauduin_alex]

Ok,

Thanks very much, at least I won't spend more days checking cables, grounding, isolation transformers and the schematic. That's why I did not understood why on previous ship it was Ok and this one is more crappy. Was about to think that the batch of DUs I have were all defectives.

I agree that you need one in JKF that works, very tight spots.

Anyway, pictures are still welcome if you have some.

[Fargoo]

Have you tried a new TCIU? Also try plugging an external monitor directly into the front of the TCIU and see what sort of image you get.

We don't look after any -300's at the mo but from what I remember you can isolate each camera with a CB on the front of the TCIU to see if any one camera is affecting the image of all 3.

Just some ideas it might be worth trying.

p.s. The external monitor will need to have an NTSC input, the front fitting is BNC.

[Cubbie]

Try using it after you have deiced/anti iced- then you will appreciate even more how good the picture is,= pretty much useless. Its only a guide at the end of the day...

[bauduin_alex]

We did try to put a scope at the connector by removing the DU and check for signal quality. It is good there, bit of noise but OK.
If with put a TV monitor with NTSC input picture is good. The only problem is at night, where the DU gives us some black "lines", regardless of ground cam lights on or off. At some spots where picture is darker we've got a lot of noise. Do I don't know the kind of filters and processing Honney does on the input. Either it is raw input not filtered and they have a dedicated ship that is not doing any kind filtering on the NTCS signal.

[Fargoo]

Don't really know what to suggest, if the picture is ok at the front connector of the TCIU then that suggests the cameras and wiring to the TCIU are fine.

Output from the TCIU is co-axial cable direct to the DU's so thats where your problem must lie (or a duff TCIU).

[lloyd_dsouza]

Hey guys,

You all sound like ur professional engineers on B777. well i hve just begun my career at a line station. would u guys help out wid its technical aspects and do we hve any maintenance videos, where we can download these from?