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M > MERLIN > Tonto   


The Tonto was the same model as the ICL OPD and the Telcom ComputerPhone which was intended for Australian market. Like the ICL version, the Tonto was sold only in the U.K. It was born thanks to a collaborative venture between British Telecom, ICL and Sinclair Research. The designers idea was to build a centralized desktop information system able to access online services, mainframes and other similar systems through the British Telecom network.

It was essentially a Sinclair QL at heart, featuring the same 68008 processor. Applications software were stored in plug-in ROM cartridges or Microdrive tapes. Sadly, both of them were not compatible with QL interfaces and microdrives format and the specific Tonto O.S. couldn't run ordinary software made for the QL, even in BASIC language.

However, the most interesting aspect of the Tonto was its telephony integration. Its internal modem (300 an 1200/75 baud) could manage two telephone lines, and the Tonto, could be used as an intelligent answering machine thanks to its synthesised voice response (but no record capabilities), a Prestel terminal for Videotext services as well as a specialized peripheral and multi-protocols terminal for mainframes. Several interconnected Tonto's also could automatically exchange files and information between them.

Below are prices for the Tonto at is launch, taken from a BT promotional video for the Tonto, dated 29-4-1985.

£1245 Basic Mono Machine
£1375 Basic Mono Machine with Xchange
£1675 Colour Machine
£1805 Colour Machine with Xchange
These are all Excluding VAT.

So these are the final prices.
£1462 Basic Mono Machine
£1615 Basic Mono Machine with Xchange
£1968 Colour Machine
£2120 Colour Machine with Xchange

Then you had an optional printer and many optional ROM packs. This was quite an expensive piece of desk accessory in its day.


Contributors: Pete (UK)

Additional information from Ray Axford:
Apart from the black and white screen that came with the standard one, you could also get larger 14" colour monitor. You could also attach by ribbon cable an additional plug-in double external 3.5" floppy drive. I used to maintain these for British Telecom and have the technical manual.
I used it for many years, extracting info from Prestel network. Lovely machine - nothing to match even today, with the built in handset on the keyboard. You could also use it hands free, with loudspeaker.

About the "T" logo, Stan Lee specifies:
I recently noticed the rather bizarre T on the Merlin Logo. I knew I recognized it somewhere-- Then it hit me. That T is the 2nd half of an old BT logo... that's probably why there's a phone attached, I suppose.

Tim Jenner adds:
The Tonto was pretty unreliable - powered up all the time, the PSU's eventually died. The microdrives were less than perfect too.
You could get expanded rom packs including more memory, but most common was the Exchange rompack which included the Psion Exchange office suite. Quill was excellent!

Bill Perry reports:
These were sold through BT local area sales as well as into bigger projects through BT Field Services. The bigger projects included Customs & Excise at ports and the Home Office Prison Services (HOPS) project. The tape drives were unreliable!

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Some of the less well-known things about it :-

1) It had a dual micro drive unit as standard which, *shock horror... gasps of disbelief* actually worked and worked well, especially with european manufactured microdrive cartridges that were sold for the Tonto.

2) It was supplied with either a monochrome display (as was the Tonto i used/inherited as a personal home computer - obtained legitamately via BT) which was fairly compact, or a larg-ish colour monitor. Notably, the main PSU was embedded in the monitor and the Tonto has no on/off switch.

3) It was prone, if misused, to PSU failures - this usually happened when people frequently shut down (at the power point) the computer. The computer itself, being a combination telecommunications device/x.25 protocol networked message terminal and application orientated desktop computer, was designed to be left switched on 24/7 (only powered off for mainenance work purposes or relocation) and the monitor could be put to sleep (i.e. the front panel button on the display simple shut off the LT side of the display electronics).

4) The commonly sold matching printer was a usually a Tonto rebranded OKI Microline 192/193 - effectively the OKI Microline equivalents to Epson FX80/100 printers. These were often serial and parallel interface equiped, as as far as printers go, were pretty fine reliable items - the 193 i had outlasted the Tonto by many years and made Seikosha GP series unit look like cheap and nasty junk.

5) Probably the least well known accessory (which was an aftermarket item) was a combination dual floppy drive unit (double-density 3.5 inch items which wrote to a format which was PC readable/writable, and with a couple of bytes rewritten, data could be exchanged via 3.5inch disc with Atari ST computers). This dual drive unit also had a full Centronics interface and a full breakout RS232 interface. I was one of rare beasts who had that mystical almost mythical addon.

Aside from it''s X25 phoneline based message exchange function, it was fully equipped with a good terminal/comms feature built-in the resident firmware, and made a very good BBS access device (which i took a lot of advantage of during cheap rates and weekend rates).

As for the two line cords for the phone and data connections - it would operate just fine using one, since you could $ which line was used for data operations and the phone used line one cord (but you could exploit the second line for additional voice telephony use - assuming you bothered to actually RTFM, which most users i know of never actually bothered to do).

Whilst i never owned any ''ROM Packs'', i had various pieces of official and unofficial software for it on microdrive, some ported from the QL and were ports originating as ICL OPD hacks. One of which included a disassemble which i used frequently to snoop into the complete undocumented firmware.

But the rarest (because everyone seemed to mislay them) common part was the formatter microdrive - yeah, you had to use a microdrive cartridge to format a blank cart. Needless to say, since i had about twenty sets of four-pack blank sets, i made various dupes of the software carts and formatter cart and had them stashed for safe keeping and NEVER used an original as a working copy.

All in all, a very pleasant machine to use for it''s comms/telephony/application workstation designed use - it''s usefulness far outweighed it''s flaws, at least in the eyes of this extreme user (i did 90$ of my documentation using it, and used it to prepare plain ascii files for Ventura and Postscript with it, since it was far more comfortable for extended use than the machine i was supposed to use for work).

It probably looks and feels to anyone today like a mutant crossbreed of a games console and a toy kiddy typewriter with a display, but it (and in OPD guise) was definately a bit of an unappreciated landmark in the history of the transition of comms from electro-mechanical TTY (such as teleprinters) towards the more ''domestic'' non-Telex use of electronic tty comms. I fondly remember it for that, as much as i fondly remember the Puma and Cheetah teleprinters as landmarks (in Telex terms) the transitional era of computer-technology based teleprinters.

Now if that doesn''t reveal my aged former 80s computer kiddie status..... :)

Saturday 13rd January 2018
''CABBIK'' (England)

I remember these - saw one in a telecom museum some years ago.
It was a rebadged Tonto obviously for Australian Telecom and had two phone plugs - one for a voice line and one for data AFAIK - if you got a crossed line it would spit out garbage on screen or $ the connection (randomly between the two)
you needed two phone lines to use one - so you had to be pretty rich.

Sunday 11th September 2011
Erik N (Australia)

Hello all,

I have recently acquired a BT promotional video for the Tonto, dated 29-4-1985.
This gives the prices for the Tonto at is launch.

£1245 Basic Mono Machine
£1375 Basic Mono Machine with Xchange
£1675 Colour Machine
£1805 Colour Machine with Xchange
These are all Excluding VAT.

So these are the final prices.
£1462 Basic Mono Machine
£1615 Basic Mono Machine with Xchange
£1968 Colour Machine
£2120 Colour Machine with Xchange

Then you had an optional printer and many optional ROM packs.
This was quite an expensive piece of desk accessory in its day.


Monday 15th December 2008
Pete (UK)


NAME  Tonto
TYPE  Professional Computer
ORIGIN  United Kingdom
YEAR  1985
END OF PRODUCTION  maintained up to 1993
KEYBOARD  Full stroke 73-key with numeric keypad
CPU  68008
SPEED  7.5 MHz
CO-PROCESSOR  Sinclair ULA custom chip
RAM  128 KB, up to 256 KB + 2 KB of battery-backed RAM
VRAM  32 KB (from the main RAM)
ROM  128 KB, up to 320 KB using ROM packs
TEXT MODES  42 or 64 or 84 chars. x 24 lines
GRAPHIC MODES  256 x 256 (8 colors) / 512 x 256 (4 colors)
SOUND  TI TMP5220C speech synthesiser / built-in loudspeaker
SIZE / WEIGHT  44 (W) x 26.5 (D) x 6.8 (H)
I/O PORTS  Custom connectors for ROM pack and Telephony module, Serial printer, RGB Monitor
BUILT IN MEDIA  2 x 100 KB microdrives
OS  Tonto OS
POWER SUPPLY  Power is supplied by the monitor
PRICE  £1,500 at start. Sold to British Telecom staff for £100 complete when BT stopped to maintain them.

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