The awesome Harlequin 128K rev 2D DIY kit!

This Harlequin rev 2D kit includes a AM29F040B chip containing the ZX Diag software, and instructions how to use this ROM.

Since the AM29F040B chip is an EEPROM, you can reuse (parts of) it for any purpose, if you have a universal programmer such as the MiniPro.

Introduction

The Harlequin rev 2D is a completely compatible ZX Spectrum clone, but without the ULA.
It's built up completely of parts that can still be obtained easily.
You can build your own complete ZX Spectrum Toast Rack (clone) yourself!

The Harlequin rev 2D has stereo audio output at the right 3.5mm socket.

A fun challenge!

The Harlequin kit consists only of through hole parts, making soldering easy (the one SMD part is already presoldered).

What you need to assemble the kit is:
- a soldering iron + solder
- basic skills and creativity
- some patience! The kit will keep you busy for several hours.

The included comprehensive assemly manual includes some important hints and lots of instructions.

Package contents

This large kit consists of:

- The (unassembled) Harlequin rev 2D printed circuit board
- Presoldered SMD part: AD724 RGB to NTSC/PAL Encoder
- All parts (except ZX Spectrum ROM) to complete the Harlequin rev 2D: discrete parts, IC's, IC sockets, connectors, etc...
- The ByteDelight complete and comprehensive 16 page DIY assembly guide to the Harlequin rev 2D!

The discrete parts are packed in bags with sequential numbers corresponding to the manual, and the bags also show the part numbers corresponding to the PCB.

ROM

No ZX Spectrum ROM is included because of intellectual property rights.

Original ROMs you can use, if you obtain one:
- ZX Spectrum 48K ROM: this will also make 128K games work fine on this Harlequin 128K board, but you do not have the 128 Menu and 128 BASIC with a 48K ROM.
- ZX Spectrum 128K 'toastrack' ROM
- ZX Spectrum +2 (grey model) ROM

Known working programmable ROM types which can be used on this board, by configuring some jumpers, are:

- 27(C)256 EPROM
- 27(C)512 EPROM
- AM29F040 EEPROM (included, with diagnostic software)

! 28C256 is incompatible with this Harlequin board ! 

What is needed to finish the kit

To use the finished Harlequin board, you will need:

1. A ZX Spectrum ROM

This board does not include a ZX Spectrum ROM, which is needed to make the board work.
You can source a ZX Spectrum ROM, or use for example the licence free SpectrumSE rom.

2. A ZX Spectrum case with keyboard
E.g. an original or replica ZX Spectrum rubber keys case - yes, the Harlequin 128 fits in a rubber-key case and works with that membrane!
Or a ZX Spectrum Plus case.
Or any other ZX Spectrum case, like the DK'Tronics, Lo Profile or Saga.

3. A TV with composite video or RGB input

4. For video output: an RCA cable, or RGB cable compatible with this board

5. An 8V - 14V power supply
With 5.5mm outer and 2.1mm inside diameter plug, and with the center pin having the negative voltage!
Most power supplies have the positive voltage as center pin.
Make sure you use a power supply with the correct polarity!

Compatible add-ons

To make loading games easy, you can use a storage interface like a DivMMC EnJOY! PRO series SD card interface.
You can also use Spectranet: the one and only ethernet interface for the ZX Spectrum.
And all kinds of other interfaces are compatible!