Minstrel 4th Jupiter Ace Compatible PCB Set + Preprogrammed Parts

This is the PCB to build a Tynemouth Software Minstrel 4th computer and keyboard. The Minstrel 4th is a Z80 based 8 bit computer which is a Jupiter ACE compatible, and as such is programmed in Forth (rather than BASIC as used on most other similar machines). It has an RC2014 expansion bus, 48K of RAM and improved composite video output. 

RC2014 I/O modules can be added using the RC2104 bus on the side, either individually or using something like the RC2014 backplane 5 to add multiple modules.

The PCB is the same form factor as the ZX81, but is intended to be built as a standalone computer with it's own tactile switch keyboard, or other external keyboard options.

Also included is a pre-programmed ROM and microcontroller which acts as a CRT controller to provide the video timing, and allows for PAL or NTSC video as well as black on white or white on black characters. 

This auction is for the three PCBs and two pre-programmed parts only. The parts required are all through hole 0.1" pitch, and are all modern parts still in production (with the exception of the the 48 pin video RAM chip which has recently gone out of production). 74HC series logic chips should be used giving the board a current consumption of around 65mA. Parts availability is a little tricky at the moment, so make sure to check the parts list (attached below) to ensure you can source all the parts required.

This is the last stock of the V4.26 boards.

More information on my blog:

http://blog.tynemouthsoftware.co.uk/2020/05/minstrel-goes-forth.html

62032_el 4th Build Instructions v4.26b_1f58.pdf [1487.78] KB