Which pin on the Microvitec CUB socket is the composite in?

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Commie_User
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Which pin on the Microvitec CUB socket is the composite in?

Postby Commie_User » Wed Mar 21, 2018 11:17 pm

I heard tell that it uses a composite-in for sync but that it views well enough through that alone.

If it does, would I connect my VCR, modded Atari 2600 or C64 straight to it?

dp11
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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby dp11 » Thu Mar 22, 2018 3:38 am

A standard cub doesn't do composite in. You need an extra Pcb which is rare.

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1024MAK
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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby 1024MAK » Thu Mar 22, 2018 9:20 am

Don't get confused between composite sync and composite video.

Composite sync is a signal where the horizontal and vertical synchronisation signals are combined.

Composite video is a signal where the horizontal and vertical synchronisation signals are combined and a monochrome video signal is mixed in as well. If a colour encoding system is in use, such as PAL, NTSC etc, then the colour signal will be added also.

With some display systems, they are often happy with a composite video signal fed to their composite sync inputs. But the reverse does not work...

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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby Commie_User » Thu Mar 22, 2018 1:57 pm

Thank you.

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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby crj » Thu Mar 22, 2018 4:41 pm

1024MAK wrote:With some display systems, they are often happy with a composite video signal fed to their composite sync inputs.

I believe other displays, especially ones from NTSC-land, are happy with composite video on their green input, because that's how "component video" works.

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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby 1024MAK » Thu Mar 22, 2018 9:16 pm

crj wrote:
1024MAK wrote:With some display systems, they are often happy with a composite video signal fed to their composite sync inputs.

I believe other displays, especially ones from NTSC-land, are happy with composite video on their green input, because that's how "component video" works.

Ahh, but that would then be RGB with sync on green (SoG or RGsB) (as opposed to RGB with separate sync input (RGBS) or RGB with separate H and V sync inputs (RGBHV)). See here.

Some of the 625 line 15625Hz 50Hz monitors at my work use RGB SoG 8)

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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby crj » Thu Mar 22, 2018 11:04 pm

Nono - I actually mean composite video on the green input.

In NTSC-land, YPbPr with sync on luma is the norm, rather than RGB with any of its syncing variants. Devices are often capable of accepting/emitting composite video on Y, instead of having a separate composite socket.

NTSC/PAL dual-standard devices usually map Y=G, Pb=B, Pr=R when handling RGB, which (a) means they'll also cope with PAL composite video on the Y/G socket and (b) is probably why PAL-land chose sync-on-green instead of sync-on-blue or sync-on-red.

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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby 1024MAK » Thu Mar 22, 2018 11:52 pm

crj wrote:Nono - I actually mean composite video on the green input.

In NTSC-land, YPbPr with sync on luma is the norm, rather than RGB with any of its syncing variants. Devices are often capable of accepting/emitting composite video on Y, instead of having a separate composite socket.

NTSC/PAL dual-standard devices usually map Y=G, Pb=B, Pr=R when handling RGB, which (a) means they'll also cope with PAL composite video on the Y/G socket and (b) is probably why PAL-land chose sync-on-green instead of sync-on-blue or sync-on-red.

Well, Y or luma is close to monochrome composite video...

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Re: Which pin on the Microvitec CUB socket is the composite in?

Postby crj » Thu Mar 22, 2018 11:56 pm

1024MAK wrote:Well, Y or luma is close to monochrome composite video...

Close? I thought it was monochrome composite video.