How to recognize the revision of QL motherboard?

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grafvonb
ROM Dongle
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How to recognize the revision of QL motherboard?

Postby grafvonb » Sat Feb 08, 2020 8:13 am

I have six QLs and just wanted to categorize them.

How can I recognize the revision of a motherboard without dismounting micodrives to flip the board (I've seen revision once on the backside of the board).


Loving QL & ZX Spectrum & Amiga...
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tofro
QL Wafer Drive
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Re: How to recognize the revision of QL motherboard?

Postby tofro » Sat Feb 08, 2020 8:38 am

Issue 5 boards have a number of zero-Ohm resistors to the bottom right of the ROMs (JU1-JU6) to set up the ROM/EPROM configuration. You won't find them on issue 6 boards. Also, they have a MOLEX connector for the upper case LEDs instead of the fiddly connector on the issue 5.
From the outside, it's even easier: Provided your board has never been changed, any signs of "Samsung" and "Made in Korea" are strong clues towards issue 6 inside.

Tobias


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grafvonb
ROM Dongle
Posts: 35
Joined: Sat Jan 05, 2019 7:54 am
Location: Frankfurt/Germany

Re: How to recognize the revision of QL motherboard?

Postby grafvonb » Sat Feb 08, 2020 9:01 am

Many thanks tofro. The hint with resistors did the trick. Additionally I have just found this tremendous site about QL's motherboards: http://www.sinclairql.net/build_standards.html


Loving QL & ZX Spectrum & Amiga...

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