Tag Archives: Board

Refurbishing a 48K Rubber Keyed Sinclair ZX Spectrum – Pt.4 Custom Composite Video Mod

Now I had the Spectrum PCB fully working, I wanted to add a Composite Video modification to round off all the refurbishments. I had already used a neat circuit advised by Andrew Gostling when I repaired a previous machine. Although … Continue reading

Posted in Renovation | Tagged , , , , , , , , | Comments Off on Refurbishing a 48K Rubber Keyed Sinclair ZX Spectrum – Pt.4 Custom Composite Video Mod

Refurbishing a 48K Rubber Keyed Sinclair ZX Spectrum – Pt.3 Upper RAM Replacement

As I had assertained earlier, the 48K Rubber Key Spectrum I was refurbishing required it’s Upper RAM to be repaired. Since the chips inside of the machine were old, I elected to replace them with a complete Upper RAM Module. … Continue reading

Posted in Renovation | Tagged , , , , , , , | Comments Off on Refurbishing a 48K Rubber Keyed Sinclair ZX Spectrum – Pt.3 Upper RAM Replacement

Diagnosing 48K Spectrum Upper RAM Faults

By way of a break from the refurb posts; I was recently part of a conversation on FaceBook regardig a coulple of 48K Rubber Key Sinclair Spectrums. Both were proved to have faulty Upper RAM problems by issuing the command … Continue reading

Posted in Renovation, Repair | Tagged , , , , , , , | Comments Off on Diagnosing 48K Spectrum Upper RAM Faults

Refurbishing a 48K Rubber Keyed Sinclair ZX Spectrum – Pt.2 Replacing the Regulator

The poor 7805 in any Sinclair Spectrum always works really hard. It was probably the best solution when the machine was designed but things have moved on. Switch-mode technology has improved and reduced in size. Therefore, when refurbishing any Sinclair … Continue reading

Posted in Renovation | Tagged , , , , , , | Comments Off on Refurbishing a 48K Rubber Keyed Sinclair ZX Spectrum – Pt.2 Replacing the Regulator

KiCad

KiCad is an EDA program, similar to Eagle, Altium and the like. I last tried it some years ago and found it to be very difficult to use, not least because of the inevitable steep learning curve that all CAD … Continue reading

Posted in Building, Design, Uncategorized | Tagged , , , , , , , , , , , , | Comments Off on KiCad

ZAViouR Demo and plans

Development continues on ZAViouR Boards v1.01 and v1.02. With a simple bit of Arduino code, you can insert Z80 Hex coded machine code into the ‘Sketch’ via bin2h.exe then compile and run it. Demonstrated here with a simple routine to … Continue reading

Posted in Building, Construction, Design, ZAViouR | Tagged , , , , , , , , , | Comments Off on ZAViouR Demo and plans

ESP8266 ESP01/03 Flash-Prototype Board

The ESP01/03 Flash-Prototype Boards arrived from the fabricator. Good quality boards in a reasonable time. Although not Hackvana (Sorry Mitch, I’ll be back for the next batch!). Here you see two of the boards, one populated with an ESP-01 module, … Continue reading

Posted in Design, ESP8266 | Tagged , , , , , , | Comments Off on ESP8266 ESP01/03 Flash-Prototype Board

Summer Developments

It’s been busy at ProjectAVR. I’ve been squirreling away, making up minDUINO kits for the Scouts JOTA event. They are almost finished now. Just a few last minute additions on back-order. The assembly instructions are complete with included circuit diagram … Continue reading

Posted in Building, Design, UKHASNet | Tagged , , , , , , , , | Comments Off on Summer Developments

ICSP to Breadboard Adaptor

Frustrated by having to poke jumper wires into the socket of my AVR ISP MkII every time I wanted to program a breadboarded AVR, I quickly built an adaptor from strip board. It consists of a 6-pin shrouded header plug … Continue reading

Posted in Building, Equipment | Tagged , , , , , , | Comments Off on ICSP to Breadboard Adaptor

ICSP Test Rig

On a whim, I bought a Maplin project to build. I needed an audio signal generator for something I’m planning and the £15.99 Function Generator Kit seemed to fit the bill. I have a very local Maplin shop where the … Continue reading

Posted in Building, Tools | Tagged , , , , , | Comments Off on ICSP Test Rig