The Sinclair QL Forum

I've picked up a non-working Opus Discovery 1 for one of my ZX Spectrums

Once I can get it working the plan is to install a 6116 & New ROM & a spare GoTek as the main drive

Currently, I haven't opened it up yet, I can hear the fan running (at least I hope it's a fan!) but get no output from the ZX but do get a garbled output from the composite out on the back of the Opus

Was wondering if anyone has experience of these and could give me any tips on what to look at/test please?

Many thanks

t0nyt wrote:I've picked up a non-working Opus Discovery 1 for one of my ZX Spectrums

Once I can get it working the plan is to install a 6116 & New ROM & a spare GoTek as the main drive

Currently, I haven't opened it up yet, I can hear the fan running (at least I hope it's a fan!) but get no output from the ZX but do get a garbled output from the composite out on the back of the Opus

Was wondering if anyone has experience of these and could give me any tips on what to look at/test please?

Many thanks

IMG_4552.jpeg

The video port at the back of the opus is not composite. It is center ground.

XorA wrote: Mon Mar 03, 2025 6:17 pm The video port at the back of the opus is not composite. It is center ground.

Ok, thanks

Have taken it apart now. No fan, the noise was from the floppy drive

Will try to find out what power the transformer is mean't to put out and check that first

Will then try re-seating (with a clean of the sockets) the socketed ICs & also try replacing the 40 pin IC

PSU will be 5v and 12v for floppy.

XorA wrote: Mon Mar 03, 2025 6:33 pm PSU will be 5v and 12v for floppy.

Ok, but it's also mean't to power the spectrum at 9v? Would that likely be done via a regulator please?

I'll check the spectrum schematics to see which lines carry the power on the expansion port and see what voltage I'm getting coming out of the opus

Many thanks

Seems the ZX Spectrum power is a lot more complicated than I thought, I just assumed the opus supplied 9v!

Opus Discovery Maintenance Manual:
https://www.bytedelight.com/wp-content/ ... Manual.pdf

Cristian wrote: Mon Mar 03, 2025 10:32 pm Opus Discovery Maintenance Manual:
https://www.bytedelight.com/wp-content/ ... Manual.pdf

Thanks Christian, helpful reading

Have also been skimming thru some world of spectrum threads

Am going to check all the power rails first (now I’ve got my head around how the opus is able to power the speccy - wish I understood electronics but it’s too late to learn what I’d like to now!)

Many thanks

I wondered why I had 3 loose wires

When I took the case apart I ripped the regulator off!

I’ll have to fix that before I can test the power rails

Luckily one of the heat shrink sleeves stayed attached to the regulator so at least I know which way around to re-attach it

t0nyt wrote: Tue Mar 04, 2025 7:53 am Thanks Christian, helpful reading

My pleasure