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Author Topic: SCART/Peritel Cable issue. (Read 184 times)

Offline JihemB

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SCART/Peritel Cable issue.
« on: 2018.June.24. 10:01:39 »
Hi Enterprise Forever forum members.

I just enter my very first Enterprise computer in my 8 bit collection and I would like to have a nice RGB SCART output for it.

I ordered such a cable from a Spanish website (RetroCables) but it doesn't work on two of my TV sets : My old CRT Philips and by Panasonic Plasma. In both cases I have a grey screen on which I can barely see the b&w image of the computer. I think this could be a pin 8 or 16 (switching) issue but the guy from the website claims "the cable was fully tested before shipping".

So my question are :
 - How can I sort out which part (cable or Enterprise connector) is faulty ?
 - Is there another place where I can order a trusted SCART cable ?

Thanks in advance for your help.

Offline Zozosoft

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Re: SCART/Peritel Cable issue.
« Reply #1 on: 2018.June.24. 10:29:29 »
Welcome here!

With RF cable your machine working?

It is a common motherboard failure when the internal 12V circuit broken. It is for the video circuits, and also it is the 12V output on monitor connector for the Scart switch signal.

Then first check 12V are present on the Scart plug?

Connector pinout and the commonly used Scart cable wiring at bottom of this page.

I bought cables from Spain and it is worked for me. I will check which resistors used.

It is a more than 30 years experience: some TVs need to play with the resistors values.

Online Dr.OG

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Re: SCART/Peritel Cable issue.
« Reply #2 on: 2018.June.24. 10:37:26 »
Take a look to the last picture on the following site (recommended in the previos post as well):

http://enterprise.iko.hu/pinouts.htm

If 12V is present on pin B6 of EP128, perhaps the resistors are missing from your cable (you can measure the resistance between the corresponding pins of the connectors with a multimeter, or simply disassemble the housing of the connectors), this may cause similar symptoms. In this case complete the cable adding the necessary resistors (I recommend to use 330 instead of 100 Ohms in cases of R, G, B and CS signals), they will comfortably fit into the housing of the SCART connector.

Another topic related to appropriate resistor values:
https://enterpriseforever.com/hardware/resistor-values-for-scart-cable/

Best regards: Gábor
« Last Edit: 2018.June.24. 10:44:15 by Dr.OG »
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Offline JihemB

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Re: SCART/Peritel Cable issue.
« Reply #3 on: 2018.June.25. 15:12:51 »
Hi.
Thanks for your suggestions.

Yes the RF out is working.

I'll have a look at the B6 pinout of my Enterprise first (what is the ground pinout, B2 ?) to check for 12V, then I'll have a look at the SCART cable pinout and check for resistances included.

Best Regards.

JihemB

Online Dr.OG

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Re: SCART/Peritel Cable issue.
« Reply #4 on: 2018.June.25. 15:20:49 »
...
I'll have a look at the B6 pinout of my Enterprise first (what is the ground pinout, B2 ?) to check for 12V, then I'll have a look at the SCART cable pinout and check for resistances included.
...
Yes. A2 and B2 are both GND/0V pins.
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Offline Zozosoft

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Re: SCART/Peritel Cable issue.
« Reply #5 on: 2018.June.26. 20:36:04 »
I measured my Spanish cable: it is as the well know schematic. 100 Ohms on colors and sync, 12V to pin 8, and 470 Ohm at pin 8-16.