Yeah, where do I start?  Tandata Design Consultants was running as a modem
designer back before '84, when I first was introduced by a colleague at uni
who had worked there for a while. I remember someone saying that all the
honest people from Tangerine went to Tandata, and everyone else formed Oric!

By '84, a project had just been conceived called "Minerva". It was a
desktop comms station, with a hands-free phone, nice keyboard, modem,
TV/Monitor, a little LCD panel, and tons of battery-backed RAM. It had a
word processor, address book, spreadsheet, etc ... precursor of a PDA,
really.  It was a very ambitious project, but with enough comms emphasis
that the company had the expertise to build it.

I worked there for the three summer vacations during my degree. Over that
time, more and more people got sucked into Minerva, until, by '86, I and
one colleague were about the only people *not* working on it!

By that time, the machines were all built, and they worked, and they were
being sold, and it was wonderful ... except that there was a bug. After a
week, or a month, but sometime, your Tandata PA (as the product was called)
would crash and require a cold boot, losing all your addresses and docs
which were held in the battery-backed RAM.  And there was no backup
facility, so you tended to lose everything -  a fact that meant that there
was *absolutely* no room for bugs.

It took months and months for the problem to be solved, because it was so
intermittent - long after I'd left, it turned out there was something
special about the ROM's ZIF sockets, and they would fail over time
(corrosion maybe? can't remember).  Of course, I imagine that there were
lots of other "candidate" bugs that were swept up in the process. But as a
result, the product started well, but never really sold once this problem
became an issue. The ICL "One-per-desk" came out, too, and did more or less
the same stuff, but it had a (ZX-style) microdrive built in, so it didn't
need to be as robust.

The PA never recouped its development costs, and by about '87/'88 it killed
the company, which ended up being bought out by the firm that fabricated
its products (AB Electronics, in Wales).  The commercial office (Tandata
Marketing Ltd), in Malvern, kept going for a while, I think.

I thought I'd add a bit more to Bill Witts'
comments about Tandata, since the company is still going, albeit in a different
form from the days when he was there. I remember him from my days at Tandata
Design Consultants in Cambridge, and while it is true that a lot of the company
was tied up working on the PA (I still have mine, and it still works!),
there were other intersting projects giong on that he didn't mention. We won a
contract to develop a product for 'the South Limburg Project', which was, in a
way, another forerunner of the Internet, but using banks of Philips
laservision disc players instead of servers. The terminal was a TV receiver
with a framestore, teletext receiver, and either a cable modem or a DTMF based
backchannel, through which page requests were sent to the server, and the pages
were delivered as a single video field on a dedicated RF channel, each one
tagged with a teletext encoded address to identify the destination receiver.

I never saw it in full operation - South Limburg is in the Netherlands - but it
looked an impressive bit of kit, and performed a very impressive freeze-frame
function on broadcast TV using a single button on the IR remote. We were also
developing a line-powered modem, which Sinclair were going to use on their
version of the PA (can't remember it's launch name), but they never got beyond
prototype because Sinclair went into receivership at around the same time.

The whole Tandata business was acquired by AB Microelectronics in 1989, who
tried to move it to South Wales. In the end, only about 7 of the marketing
staff stayed with the company, and it was progressively sold off over the next
two years. Tandata Design Consultants staff bought their bit back and carried
on for a while as an independent consultancy, also providing a repair service
for customers' kit, before folding, and four of the remaining staff in Wales
bought the rest, renamed as Tandata Systems Ltd. This was moved to Newbury in
1992, and developed the databroadcast side of the business, which began with a
staff information terminal for Heathrow Airport. It went on to provide data
broadcast head end systems and receivers to various companies in the betting
and financial services industries until 2001, when the decision was made to
concentrate on the passenger transport information systems business, which had
been steadily growing since the first check-in desk system was supplied to
Birmingham Airport in about 1993. There are around 70 sites in the UK currently
using their flight information system, Axis, or the bus interchange system,
BIDS. The company was developing on-street interactive talking timetable
systems, and real-time information systems using bus position reporting, when
it was acquired by ACIS in 2005. It still trades under the Tandata name, and is
still based in Newbury, although there are plans to move it to Cambridge, where
the parent company's development team is located.