New hardware...

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RWAP
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Re: New hardware...

Post by RWAP »

If there is no response to the keyboard, then it sounds as though (presuming the membrane is OK), that it is a motherboard failure.

This could be a ram problem, although I would normally expect the ram test to at least start.

It is more likely to be one of the socketed chips has failed - 8302 or 8301 are the most likely - the 8302 is plugged into QIMI, so I would recommend removing QIMI and plugging the 8302 directly into the motherboard socket (and the ROM chip at the other end of the QIMI unless you have Minerva...)

The first step if that makes no difference is to remove each socketed chips and push them back into their sockets to break any carbon deposits on the legs.

Other than that, you may have to try some replacement chips.


thorsinclair
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Re: New hardware...

Post by thorsinclair »

OK, I have removed the QIMI and tried again with no result. Power on light OK, no reaction to F1 or F2. But I noticed a small damage: There are 2 large paper like cables going from the keyboard to the mainboard. One of them is damaged. How are this sockets on the mainboard working? I tried to remove this kables without success.


thorsinclair
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Re: New hardware...

Post by thorsinclair »

Checked this one myself, cables are again connected and look OK. Result remains the same. No reaction on F1 and F2 and no screen output :(


RWAP
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Re: New hardware...

Post by RWAP »

It is likely you will at least need a new keyboard membrane - if the membrane tails are already damaged, they probably have cracks elsewhere which will stop them from working.

It is hard to diagnose at a distance.

It could just be that your keyboard membrane has failed, so you cannot press either F1 or F2 to get past the first screen. If that worked and the microdrive started up, then it is most likely just the video out chip (MC1377P) which needs replacing...

You say you connected the QL via a SCART lead - have you tried connecting it to TV using normal aerial lead?

Also, as I say try taking each chip out of its socket and replacing it.


thorsinclair
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Re: New hardware...

Post by thorsinclair »

Hi,

First of all, thank you. You have been very helpfull with all this info. The QL is still dead and I have to consider what to do. As I am not very good in fiddeling this hardware things I need somebody who does the work for me. In general the machine is in very good conditions but I have to consider to repair it or to go on with Q-Emulator. Only thing is that I wanted to check my old progs I wrote at its time but they are all on microdrives ...
Will think about that over the weekend. Would you be the right person to do the repair?
Best,
T


RWAP
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Re: New hardware...

Post by RWAP »

Hi yes, I can do the repair for you but you have to take into account the costs of sending the QL to and from the UK.

Rich


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