Author Topic: CPC464 and SCART again  (Read 3412 times)

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Offline orange

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CPC464 and SCART again
« on: 11:13, 28 April 10 »
i connected pin 6 to 20 and then pin 4 to 16. it worked with one small problem; the (panasonic) tv would occasionally 'detect' again that its rgb (and not composite) and it would display 'RGB' in corner for a sec.
probably because there's not enough voltage on SCARTpin16? it was a bit annoying, so I connected +5V to 220ohms and then scart pin 16 (I left CPC pin 4 unconnected) and it works better.

if I understood correctly we can connect either pin 4 (SYNC) or pin 6 (LUM) from CPC to pin 20 on SCART? but what about SCART pin16, is there a way to make it work without the need for +5V? (would it perhaps work with 6->16 ?)

Offline arnoldemu

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Re: CPC464 and SCART again
« Reply #1 on: 11:42, 28 April 10 »
i connected pin 6 to 20 and then pin 4 to 16. it worked with one small problem; the (panasonic) tv would occasionally 'detect' again that its rgb (and not composite) and it would display 'RGB' in corner for a sec.
probably because there's not enough voltage on SCARTpin16? it was a bit annoying, so I connected +5V to 220ohms and then scart pin 16 (I left CPC pin 4 unconnected) and it works better.

if I understood correctly we can connect either pin 4 (SYNC) or pin 6 (LUM) from CPC to pin 20 on SCART? but what about SCART pin16, is there a way to make it work without the need for +5V? (would it perhaps work with 6->16 ?)
LUM is only required for green monitor.
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Offline nocash

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Re: CPC464 and SCART again
« Reply #2 on: 12:39, 28 April 10 »
What are you doing exactly?
Did you see http://cpcwiki.eu/index.php/TV_SCART_cable ?
Are you using the same connection, but still get problems?

Of course, the batteries in above schematics aren't that optimal. Using a resistor to 5V to produce 1V-3V would be better than batteries. But it with different TVs you may need different resistors. Maybe best would be using two 1K Ohm resistors:
  GND ------1K-------x------1K------5V
In the middle (x) you should get perfect 2.5V. And even if the TV drags it down a little, you should still be in the 1V-3V range. Btw. you don't have a multimeter to verify what voltage you have, or do you?

Offline Bryce

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Re: CPC464 and SCART again
« Reply #3 on: 12:44, 28 April 10 »
Have you tried the battery-less alternative pinout shown here: http://www.cpcwiki.eu/index.php/TV_SCART_cable
that works on most modern TVs.

Bryce.