The Sinclair QL Forum

I've recently purchased a second QL from Ebay, simply because it had a Trump card included!
I fired up the QL tonight, and noticed two odd things..

1. The Trump card only reports 192k RAM
2. The video output is faulty I then put the Trump card in my original QL, and it reports 896k RAM.
So I decided to open the QL I had just received, and found it has been modded! Vanpeebles suspects it's an internal RAM upgrade, can anyone shed any light on what this is?
Also if anyone knows how to fix the video output, please let me know!

Hi - this is indeed an internal RAM upgrade (128K, 256K or 512K) - the Trump Card will not work with this in place. so you would need to remove the Board.

About the video output - I have seen this on several occasions - I am not sure how to fix this, although you could try replacing the vidoe chip - I have emailed Tony Firshman to see what he would suggest

Cheers Rich!
Is there an easy way for me to find out what size this RAM upgrade is?

Thanks for contacting Tony, if he has any suggestions, please let me know!

Out of curiosity, which is the video chip in the QL?

robheaton wrote:Out of curiosity, which is the video chip in the QL?

ZX8301, on your Pic3.jpg the big one just next to the processor (processor is the big one with golden window and wires). ZX8301 is to the right.

As this QL has an internal RAM card, does it still use a ZX8301?

Here is a close up of the existing chip;

robheaton wrote:does it still use a ZX8301?

Yes, almost sure.

dex wrote:

robheaton wrote:does it still use a ZX8301?

Yes, almost sure.

Yes the CLA3210 is also the video controller, although there is also the MC1377 chip - I have stocks of both.

Tony also suggested it may be necessary to swap the modulator, but I would try these two chips first.

If there is an issue with the internal memory expansion board, then that may be affecting the ZX8301 chip which is plugged into the memory expansion!

By the way, for those not in the know - the reason why internal memory expansions were never very popular was mainly for speed reasons - external memory expansion was always quicker than the internal version (I can't remember why).

Then, speed wise, there was a later Trump Card 2 which was quicker than the original Trump Card.

Hi Rich,
As it could be any combination of 3 components, do you think it's best if I send the QL to you for repair?
Obviously I would pay you for your time.

I had a (different) video problem with my QL several years ago, and this is what I learned that time:

As written in the QL User Guide, the QL provides several different video signal outputs. If you have a chance to test your QL with different video cables/monitors/outputs, this would give a useful hint of what is broken:

If you use the RGB-output and the video is already faulty, it should be the ZX8301 or the RAM

Likewise, if you use the "Composite MONOCHROME" output and the video is faulty, it should also be the ZX8301 or the RAM

If the above outputs are ok, then the ZX8301 is ok.

If the above outputs are ok, and you only see a faulty video on the "Composide PAL" color video output, it could be the MC1377 circuit that mixes the composite color signal.

If the faulty signal is only on the TV antenna signal, that would of cause point towards the modulator.