Modded QL?

Nagging hardware related question? Post here!
User avatar
robheaton
Site Admin
Posts: 254
Joined: Fri Nov 19, 2010 5:50 pm
Location: Ormskirk, UK

Modded QL?

Postby robheaton » Sat Jan 22, 2011 8:49 pm

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
pic1.jpg
QL Startup
pic1.jpg (34.41 KiB) Viewed 3220 times


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!
pic3.jpg
QL Mod
pic3.jpg (71.9 KiB) Viewed 3220 times


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!


Current Retro Hardware :-
ZX80 Clone, ZX81 + Chroma + ZXPand + Zeddynet, Just Speccy 128, BB Sinclair QL + Trump Card Clone, Aurora + Super GC + QubIDE.
BBC Model B 32k + Datacenter + Z80 Tube, BBC Master 128k + Datacenter & 6502 Tube.
Commodore 64.
RWAP
RWAP Master
Posts: 2446
Joined: Sun Nov 28, 2010 4:51 pm
Location: Stone, United Kingdom
Contact:

Re: Modded QL?

Postby RWAP » Sun Jan 23, 2011 10:38 am

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


User avatar
robheaton
Site Admin
Posts: 254
Joined: Fri Nov 19, 2010 5:50 pm
Location: Ormskirk, UK

Re: Modded QL?

Postby robheaton » Sun Jan 23, 2011 10:41 am

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!


Current Retro Hardware :-
ZX80 Clone, ZX81 + Chroma + ZXPand + Zeddynet, Just Speccy 128, BB Sinclair QL + Trump Card Clone, Aurora + Super GC + QubIDE.
BBC Model B 32k + Datacenter + Z80 Tube, BBC Master 128k + Datacenter & 6502 Tube.
Commodore 64.
User avatar
robheaton
Site Admin
Posts: 254
Joined: Fri Nov 19, 2010 5:50 pm
Location: Ormskirk, UK

Re: Modded QL?

Postby robheaton » Sun Jan 23, 2011 7:20 pm

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


Current Retro Hardware :-
ZX80 Clone, ZX81 + Chroma + ZXPand + Zeddynet, Just Speccy 128, BB Sinclair QL + Trump Card Clone, Aurora + Super GC + QubIDE.
BBC Model B 32k + Datacenter + Z80 Tube, BBC Master 128k + Datacenter & 6502 Tube.
Commodore 64.
dex
Trump Card
Posts: 181
Joined: Thu Dec 23, 2010 1:40 pm

Re: Modded QL?

Postby dex » Sun Jan 23, 2011 7:46 pm

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.


User avatar
robheaton
Site Admin
Posts: 254
Joined: Fri Nov 19, 2010 5:50 pm
Location: Ormskirk, UK

Re: Modded QL?

Postby robheaton » Sun Jan 23, 2011 8:45 pm

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

Here is a close up of the existing chip;
qlzx.jpg
QL Chips


Current Retro Hardware :-
ZX80 Clone, ZX81 + Chroma + ZXPand + Zeddynet, Just Speccy 128, BB Sinclair QL + Trump Card Clone, Aurora + Super GC + QubIDE.
BBC Model B 32k + Datacenter + Z80 Tube, BBC Master 128k + Datacenter & 6502 Tube.
Commodore 64.
dex
Trump Card
Posts: 181
Joined: Thu Dec 23, 2010 1:40 pm

Re: Modded QL?

Postby dex » Sun Jan 23, 2011 10:04 pm

robheaton wrote:does it still use a ZX8301?

Yes, almost sure.


RWAP
RWAP Master
Posts: 2446
Joined: Sun Nov 28, 2010 4:51 pm
Location: Stone, United Kingdom
Contact:

Re: Modded QL?

Postby RWAP » Sun Jan 23, 2011 10:56 pm

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.


User avatar
robheaton
Site Admin
Posts: 254
Joined: Fri Nov 19, 2010 5:50 pm
Location: Ormskirk, UK

Re: Modded QL?

Postby robheaton » Sun Jan 23, 2011 11:20 pm

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.


Current Retro Hardware :-
ZX80 Clone, ZX81 + Chroma + ZXPand + Zeddynet, Just Speccy 128, BB Sinclair QL + Trump Card Clone, Aurora + Super GC + QubIDE.
BBC Model B 32k + Datacenter + Z80 Tube, BBC Master 128k + Datacenter & 6502 Tube.
Commodore 64.
User avatar
Oliver
ROM Dongle
Posts: 5
Joined: Mon Jan 03, 2011 10:32 pm
Location: Germany

Re: Modded QL?

Postby Oliver » Sun Jan 23, 2011 11:59 pm

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.



Return to “Hardware”

Who is online

Users browsing this forum: No registered users and 4 guests