QL to SCART

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JonB
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QL to SCART

Post by JonB »

Just a quick question here - is a ZX Spectrum +128 "toaster rack" video cable compatible with the QL's RGB output connector? I believe they are both of the same era...


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vanpeebles
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Re: QL to SCART

Post by vanpeebles »



JonB
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Re: QL to SCART

Post by JonB »

Yeah, it says the pinouts are the same but the signal voltages, and hence the built in resistors for the cable, are different.

Anyone tried a ZX cable with a QL?


JonB
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Re: QL to SCART

Post by JonB »

Well, I have as of tonight. I got a picture but there was an awful of of flickering, then the picture was lost. My LCD TV shut it off (went to a blue screen which is what it does when there is no readable signal).

Despite the flicker, it looks like a clean signal. Could it be down to the voltage
(that is, the resistors in the cable)? I'd suspect some sort of timing issue but it is working fine on UHF (TV aerial input, channel 36).


JonB
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Re: QL to SCART

Post by JonB »

This is a nasty hack...
image.jpg
..but it works. I've got a rock solid picture now! I used 470R all round rather than the 330R /390R recommended by the wiring diagram I saw but it must be well within acceptable parameters.

Serial cable is next!


JonB
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Re: QL to SCART

Post by JonB »

image.jpg
..amazing what you can do with heat glue and an old DIN plug. The red connection is a little shaky but it works well.


JonB
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Re: QL to SCART

Post by JonB »

And here is the proof. Taken with an iPad so there is a small amount of blurring evident. In reality it is clearer and less washed out.
image.jpg


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tofro
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Re: QL to SCART

Post by tofro »

Looks good!

And certainly much better than using the TV modulator.

Is it TV or Monitor mode?

Tobias


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JonB
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Re: QL to SCART

Post by JonB »

TV mode.

In Monitor mode I can't see the command line, although Quill looks the same. That's a point, I need to ask a question about these two modes... in another thread.


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Mr_Navigator
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Re: QL to SCART

Post by Mr_Navigator »

Well at least you didn't do what I did, a couple of years ago in my haste, the result can be seen below, albeit reproduced for aesthetic reasons :)
Untitled-1.png
Untitled-1.png (2.23 KiB) Viewed 5719 times
Of course this caused some amusement at the QUANTA AGM/workshop.


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