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Black and White on Scart VCR out


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Old 01-11-2010, 21:01
jonnyjonjon
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I wondered if anyone else had suffered a similar problem. I use the VCR scart feed on a Foxsat HDR to output to an RF converter that then feeds a second TV. On a regular basis it only displays a Black and White picture. They only way to cure it, but only sometimes, is to put thebox into full standby and then switch back on. Sometimes this works on the first or second attempt, but sometimes not at all. The RF converter and cables are fine, as I have eliminated these by process and elimination, using a Scart out on an adjacent DVD player. I have also tried using the video out feeds on the Humax, but these give the same problem.
It's strange as there is no pattern to this problem! Any advice?
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Old 01-11-2010, 21:40
vinnys
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Should be somewhere in a setup menu, an option to change the VCR scart type, to either RGB, S-VIDEO, or COMPOSITE, change the output type in the menu of the FREESAT+ box to see if this remedies your problem.
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Old 02-11-2010, 07:00
jonnyjonjon
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Tried that! Makes no difference.
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Old 02-11-2010, 09:58
grahamlthompson
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If you feed your local TV by scart from the hdr vcr scart does it also go monochrome ?

Somewhere you are losing the chrominance bit of the composite signal leaving only the luminance.
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Old 02-11-2010, 10:08
jonnyjonjon
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Yes it does, so therefore it points to a dodgy scart outlet on the box. If I use the tv out scart to feed the second tv it does appear in colour. It doesn't explain why sometimes if I turn the box off and on again it cures it. The box is only just over a year old so I can't get it replaced. Why would the video out also exhibit the same problem though? I have also tried a factory reset but this didn't help either.
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Old 02-11-2010, 10:12
jonnyjonjon
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I hope the HDMI output works! I don't have an HDTV so haven't used this. Was thinking this would be an expensive solution. Buy a new TV and use the tv scart out to feed the second tv. If anyone has a cheaper solution I'd love to hear it!
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Old 02-11-2010, 10:58
Badvok
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... The box is only just over a year old so I can't get it replaced. ...
First check your warranty, most these days are 2 years. Otherwise, it is probably just a broken track or solder joint in the box. Get it down to a local repair shop and they should be able to find and fix the fault quite easily and shouldn't charge you too much.
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Old 02-11-2010, 11:09
2Bdecided
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You need composite (or RGB, which also includes composite!).

If it switches to S-video, then you'll lose colour on any device expecting composite. It sounds to me like an obscure software fault, with the output intermittently switching to S-video.

It can't be a hardware fault or broken wire - the chroma doesn't go down a separate wire with composite!

Cheers,
David.
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Old 02-11-2010, 11:59
grahamlthompson
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Yes it does, so therefore it points to a dodgy scart outlet on the box. If I use the tv out scart to feed the second tv it does appear in colour. It doesn't explain why sometimes if I turn the box off and on again it cures it. The box is only just over a year old so I can't get it replaced. Why would the video out also exhibit the same problem though? I have also tried a factory reset but this didn't help either.
Do you mean TV out to feed the modulator, indicating there's no problem with the composite out from the TV scart. ?
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Old 02-11-2010, 12:51
spiney2
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As several people have said, the usual explanation would be missing chroma on s video, but doesn't seem to be.

Otherwise notoriously dodgy scart plugs, but not that either.

Since problem varies with box reset, this suggests software (unless, just by touching it, you're "mechanically influencing" the scart connector. Only needs a "bare nudge").

Try pushing in all connectors FIRMLY. You never know .....

Note a change from b/w to colour suggests s video, but since you're using a uhf modulator, could it be the tv is simply "tuning out" of the pal subcarrier? Try re-tuning it. Possibly it's the automatic frequency control cutting in or out, which would affect chroma carrier lock.

(ok ..... since you're using a uhf modulator, that's cvbs NOT s video, and re-tuning the tv is probably the cure!).
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Old 02-11-2010, 14:38
Bob_Cat
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I've seen connections which could strip out PAL CSC when they had certain characteristics. It could be poor impedance matching of the UHF modulator to the CVBS line, if it is re-generating the CSC then it could be failing to lock to the input with a bad connection.
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Old 02-11-2010, 15:11
jonnyjonjon
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Do you mean TV out to feed the modulator, indicating there's no problem with the composite out from the TV scart. ?
Yes. If I use the tv out to feed the modulator then it all works fine.
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Old 02-11-2010, 15:38
jonnyjonjon
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I've seen connections which could strip out PAL CSC when they had certain characteristics. It could be poor impedance matching of the UHF modulator to the CVBS line, if it is re-generating the CSC then it could be failing to lock to the input with a bad connection.
So, would you recommend replacing the SCART cable and /or modulator? If it was the cable it doesn't explain why I have the same issue with the Video Out cable.

On a possibly unrelated issue I can't seem to get an IP address any longer to use iPlayer. The connections are all fine (have checked by plugging my laptop in).
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Old 02-11-2010, 15:50
grahamlthompson
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Yes. If I use the tv out to feed the modulator then it all works fine.
It's a wierd one, 1 out of the three sources of composite works. No idea how they are distributed internally. Any comments Bob ?
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Old 02-11-2010, 17:04
fingerstoo
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I am just wondering if the format you are viewing is set to HD or something other than normal SD. Have you tried ensuring the display output is set to "original", especially when viewing SD broadcasts?

Normally the viewing device (TV/projector) will downscale to SD if the output signal has a higher format, or indeed the Humax itself will do this. It might be that you are losing the chrominance part of the composite signal as a result of some sort of inherent downscaling?

I may be completely wrong, but worth a try?
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Old 02-11-2010, 17:10
Andy2
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I'd suggest a slight tuning drift of the modulator. Next time it happens, see if re-tuning the TV brings back the colour.
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Old 02-11-2010, 17:25
grahamlthompson
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I am just wondering if the format you are viewing is set to HD or something other than normal SD. Have you tried ensuring the display output is set to "original", especially when viewing SD broadcasts?

Normally the viewing device (TV/projector) will downscale to SD if the output signal has a higher format, or indeed the Humax itself will do this. It might be that you are losing the chrominance part of the composite signal as a result of some sort of inherent downscaling?

I may be completely wrong, but worth a try?
Only affects hdmi, composite is always 576i
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Old 02-11-2010, 19:57
jonnyjonjon
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Done some more testing and I'm convinced the VCR scart and video out ports are at fault. The TV scart us fine as long as RGB is selected. Any of the other settings give a Black and White picture. So, is this a software issue or a hardware fault? If the latter how can i fix so that CVBS output works through any of the outputs?
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Old 02-11-2010, 20:48
Nigel Goodwin
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Done some more testing and I'm convinced the VCR scart and video out ports are at fault. The TV scart us fine as long as RGB is selected. Any of the other settings give a Black and White picture. So, is this a software issue or a hardware fault? If the latter how can i fix so that CVBS output works through any of the outputs?
RGB includes no colour information, which is why that works regardless.

To create the colour information in the box it needs to use a VERY accurate frequency for the colour sub-carrier oscillator, if this is slightly off frequency it may on the limit of your TV working or not.

Have you tried a different TV?, it may be that the TV is a little out of spec one way, and the Humax a little out of spec the other way.
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Old 02-11-2010, 21:04
grahamlthompson
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RGB includes no colour information, which is why that works regardless.

To create the colour information in the box it needs to use a VERY accurate frequency for the colour sub-carrier oscillator, if this is slightly off frequency it may on the limit of your TV working or not.

Have you tried a different TV?, it may be that the TV is a little out of spec one way, and the Humax a little out of spec the other way.
Nigel the OP is using a modulator on the TV scart to send the picture and it's in colour so presumably it must be using the cvbs out from the hdr not RGB. The same modulator fed from the vcr scart or the rca phonos to the same TV delivers monochrome. Unless you have another theory
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Old 03-11-2010, 11:27
jonnyjonjon
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Last night, I swicthed the Humax off and on again, and I started getting colour again through the VCR Scart Out that feeds my second TV. This morning it is back to normal i.e. black and white. However, I have now noticed a link between my Humax getting an DHCP address (apologies if technical language is not quite correct) and the VCR Scart Out and Composite out giving a colour signal. I've tried unplugging the Ethernet cable to see if this solves the colour issue, but it doesn't. Does seem very strange that both 'faults' i.e lack of iPlayer (because of no IP address being assigned) and lack of colour happening at the same time?
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Old 03-11-2010, 12:29
jonnyjonjon
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I have now emailed Humax Technical Support to ask what the options are for a replacement unit. I have checked the HDMI port by bringing down a HD TV from upstairs. I say HDTV - it had a HDMI port, but the picture quality on my JVC CRT TV was miles better. Then again it was a Wharfedale HDTV that was very cheap. It certainly hasn't made me want to rush out and buy a new HDTV as a main set.
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Old 03-11-2010, 14:30
spiney2
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If the problem tv is tuned into a particular uhf channel, then, it's cvbs, and the colour subcarrier is "missing".

EIther, the tv isn't tuned in correctly, or, the chroma signal isn;t being sent (Humax output settings).

What ethernet and ip address binding have to do with it, I've no idea,
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Old 03-11-2010, 16:45
fingerstoo
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Only affects hdmi, composite is always 576i
Thank you, guru. I will shut up!
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Old 03-11-2010, 17:10
jonnyjonjon
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What ethernet and ip address binding have to do with it, I've no idea,
I agree, but that's what I'm seeing.
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