Replica Softy 1 Programmer

Replica SOFTY 1 Programmer Front View


This is a modern replica of the Dataman Softy 2 Programmer, the original board was a double sided PCB but without through hole plating, vias having to be hand soldered !  This is a double sided through hole plated board with gold flash for the edge-connectors.

I have made a number of small improvements whilst keeping the layout and tracking as close to the original as possible:

This board is fitted with Omron switches and UM1111 modulator options.

Replica SOFTY 1 Programmer Top View


(It is possible to fit a 6-way Molex type header for the power connections rather than using an edge connector (as shown in the photo), unfortunately the 0V connection is at the bottom of the PCB but a link can be added to make the connection).


A further option for the keypad is to fit a keypad overlay:

SOFTY 1 keypad overlay  SOFTY 1 with keypad overlay


It uses 4.3mm high tactile switches and is avaliable from Ian Reynolds: 'Realtime' on the UK Vintage Radio forum or '55theparade' on eBay.



The original schematic in the manual has a few omissions, the most significant are that IC12 has no clock and IC6 PA0,1 connections are missing.

It was also quite hard to follow as ICs only had pin numbers and no labels.

Here's what the links do:

Replica SOFTY 1 Links

* these positions are referred to with the board on its side with the IC's the 'correct' way around i.e. pin 1 at the top


Bill Of Materials

2716 Adapter

The Programmer socket on the Softy 1 can only be used with three rail EPROMs i.e. 2708 and TMS2716, this makes it difficult to transfer images from other systems.  I have made a simple adapter which allows a single rail 2716 EPROM to be fitted, FOR READ ONLY, for the transfer of images.



The link/switch allows selection of either of the two 1K pages of the 2716.

Replica SOFTY 1 Programmer 2716 AdapterReplica SOFTY 1 Programmer 2716 Adapter in-situ



Power Supply

SOFTY 1 Power Supply


I have developed a power supply for the Softy 1 that provides the four power rails, it is packaged in a neat RS enclosure powered from a standard USB power supply.


The Softy 1 manual states that a 27V programming voltage should be connected to the board.  This is a bit strange as the Intel 2708 requires a nominal 26V Vpp (25V min to 27V max), ZD1 and TR4 drop over 3V before it even gets to the 2708 resulting in a very low Vpp ?

This power supply can be configured to either provide a nominal 29V programming voltage by fitting just D1/D2 or if required 26V by fitting IC4.  Because the output of IC3 tends to be on the high side of 30V, D1/D2 will put the programming voltage into the right range for a 2708 in a Softy 1.

SOFTY 1 Power Supply (PSU) Internal ViewSOFTY 1 Power Supply (PSU) Cable


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