Borer Data Line Driver

The second of the modems from the original Comms Room installation and a marked improvement on the previous Borer modem. This still features a metal case, but is probably about a third of the size of the 2400L discussed previously. One significant improvement, apart from the size, is that this modem could be run at various data rates, ranging from 600bps to a whopping 19200bps.

Again, this would have provided remote access to the IBM 7171 controller.

Like the previous Borer modem, this device had the same light blue cover and a black front, tho’ in this case, it is not easily removeable. A similar array of LEDs adorn the front, with indicators for DCD, RTS and both TX and RX. In addition, buttons are provided in order to apply loopback tests on the line, either local or remote and these also contributed to common issues in that old environment, where test buttons were accidentally latched when other work was being carried out on another piece of kit. Still, these were an easy fix;-) One further adornment is a thumbwheel accessible from a hole in the front, which was used to set the device’s data rate.

Around the back, along with the line terminator and serial connector, is a nice little table which shows the data rates available with this device. This also shows that this could run either asynchronously (presumably taking the line speed from the speed of the data on the serial interface) or synchronously. One hint as to the actual speed that this device provided to the end user is that the thumbwheel on the front, is set to position 4 which corresponds to 4800 Synch on the table. As I do not recall ever changing this in all the years this has been in the loft, and both modems I have are set the same, it is safe to presume that this did, indeed, run at 4800bps. What lucky folks those users were;-)

Again we see that the line termination was done using screw-terminals. It wasn’t until theses devices were replaced that we started using RJ11 cables to connect modems to BT lines, although some BT lines were actually presented this way, the modem technology lagged a little way behind.

As with the previous Borer modem, I possess a working pair of these and the glowing LEDs of one them appear in the header graphic on the site:-)

Micom-Borer 2400L

The first of a couple of posts featuring modems that used to reside on the home-made shelving ‘rack’ in the Comms Room. A monstrous unit, with a metal case so rather on the heavy side, and whose size defies its dimunitive 2400bps data speed. This would have been used to provide access to the mainframe via the 7171 controller for remote sites. At the other end of this would have been either an IBM or Memorex CRT VDU. Green-screen, natch.

Looking at the front of this, we see a dark front cover, behind which are a series of LEDs to indicate the state of the carrier, the RTS/CTS signals and the TX and RX of data. There is also a test LED, which would indicate that the unit was in test mode. This was set by a toggling a dip-switch that is revealed when the front cover is removed.

At the back, we see two V24 D-sub connectors, one for the digital I/O, and one Auxilary. This latter could have been used for a printer, I presume, but I don’t recall us ever running remote printing via these modems. Printing, if any, would have been to a printer connected directly to the VDU. In addition, there is a screw terminal for connecting the to the BT line. If we were lucky, someone (and I’m looking at you Adrian) would have actually put terminating lugs on the end of the end cable, but usually the ends of the cable were just wrapped (or not) around the posts before the screw was tightened.

The modem at the Comms Room end would have its serial port connected directly to the IBM 7171 controller and the remote modem would have the VDU connected to its corresponding serial interface. If you think that this was just one of about 20 or 30 modems ‘installed’ on the racking, then you may be able to imagine the mess that resided at the back of the old rack, with each modem having its mains, serial and line cables coming out the back and trailling off to who knows where!

Incidentally, I have a pair of these monsters, both of which still function.

Anderson Jacobson ADC212

Another device that had already fallen out of use by the time I started. Manufactured back in the days before grey or biege plastic was the norm, this little box is actually made of wood.

Opening the front half reveals the couplers for the handset plus switches for half or full (duplex, I presume) and the power switch.

As well as looking its age, it’s also showing its age as well. The black foam in the lid has gone hard and drops dust onto the coupler housing everytime the lid is closed. The foam around the couplers themselves is also going the same way, sadly, and the rubber of the couplers is also going hard:-(

Opening the back reveals the glorious components that formed the circuitry.

On the side are TTY connections for a terminal, a D-25 serial connector, labelled CCITT, plus a very proprietry mains cable.

I have no idea on the speed that this thing used to communicate at, nor do I know what systems is was used for. I doubt it was much fun tho’!

The Ultratec Supercom

Quite a nifty little unit, which you can see, still works:-) Again, quite a substantial qwerty keyboard, which emits the most awful beep everytime you press a key! From the keyboard, it doesn’t look like it has an extensive character set so would imagine it was quite limited functionality wise. It also doesn’t appear to have a serial interface. However, when you remove the small plastic cover between the acoustic cups, there is a strange printer port.

Removing the cover also reveals another little gem. This thing could run on batteries! Not, however, the ones that are in it, they must be at least twenty years old. This view also shows the acoustic cups clearly (I assure you, that brown stuff in there is not ear wax) and also the strange little printer interface.

Again, I have no idea what this was used for but it must have been in circulation for a while after I joined the organization as the mains adapter with it was tested by electrical contractors in 1995. The company had started installing PCs on desks by this time and had also started using the Internet, so who ever used this was really being left behind!

Incidentally and FWIW, I still have the original box for this, as well as the original warranty card. Wonder if I could get any support for it these days?

Actually, it does look like they still exist, and still sell acoustic couplers!

Ultratec

The Texas Instruments Silent 700 Electronic Data Terminal.

This is one of a couple of Acoustic Couplers I collected. This had already fallen out of use when I started and was going to be dumped. Actually, quite a nice self-contained unit, in its own carry case. Undo four clips on the side, and the whole lid comes away.

Once the lid is removed the device is revealed in all its glory. It has a good, solid qwerty keyboard, some extra buttons on the side and at the top, the cups for the phone cradle to rest on. I’ve no idea what this was used for, but the label says:

‘TO DELETE CHARACTER(S)
JUST ENTERED USE
SHIFT O (LETTER OH) (S)

FOR CASCAID OR LEDGER
ENQUIRY SYSTEMS’

As you can see it still has its original thermal paper roll still installed.

This rear view shows the phone cups more clearly and also its serial interface, which is a 15-way D-Sub connector. I have no idea what speed this thing ran at, but it couldn’t have been much fun to use. To anyone that complains how slow their Internet service is, just think of being in the shoes of whoever used this;-)

From ‘The Jerk’:

Navin R. Johnson: Why are you crying? And why are you wearing that old dress?

Marie: Because I just heard a song on the radio that reminded me of the way we were.

Navin R. Johnson: What was it?

Marie: “The Way We Were.”

So, when I started this job as a Communications Technician, it was obvious from the get-go that things were already changing in the communications environment of the organisation I joined. There were no immediate plans to change any of the computer systems at the time, basically mainframes were what you could get and mainframes were what you had, but on the network side, things were very different. As I said previously, there were other systems in use apart from the mainframe, but we did not get inviolved in any of that. They were looked after by the Operators, and the most involvement with those systems we had was ordering circuits from BT.

To get an idea as to the way we were, it’s probably a good idea to describe physically how things were setup. The building we were in was a rather large one, built in two timezones. One half was bulit in the 1930s and the other half added on in the 1970s, and I doubt that there is a single building anywhere that has such a mismatch in architecture and astethics! We were ensconsed in our small office on the third floor of the older building, next door to the Ops room. Next door to them was the computer operations room, where the Ops consoles, tape drives, etc., were housed. Next door to that was our comms room[1], where the modem links to the remote sites were terminated. This also contained the IBM 3274 controllers which fed the co-ax connections to the terminals that were dotted around both the old and new buildings, and an IBM 7171 asynch controller that connected the remote sites via the modem links. Above us, in the attic, was the computer room where the mainframe and it’s FEPs were housed.

At the start, our responsibilties consisted of looking after the modems, together with their remote BT lines and their links to the 7171, that were located in the comms room, the co-ax cabling for the IBM terminals and the hideous things that were the IBM 5520 systems. The fun we had with those 5520 beasts and their devil-spawned twin-ax cables is worthy of another post sometime, but the co-ax cabling wasn’t in that bad a shape. The modem stuff was a mess, however.

Racking? Cable management? Labelling? Forget it. Ok, some stuff was labelled, sort of, but the modems were just rested on a set of hand-made formica shelves, the like of which you may have in a garage. The modems, all of different sizes, were stacked any which way. Their line cables just drifted out the back of the shelving (as did the power cables) and connected to either the phone sockets or the DPs, whilst their serial cables were thrown down the back, under the floor and into the 7171. Deep joy! It wasn’t unusual to break another remote link whilst you fixed another, by either tripping over a line cable, or knocking the power out of another modem. To compound the mess, there was a 3270 co-ax patch panel located next to the shelving which, although it was in a rack and it was labelled, it was still not a pretty sight. It was also stuck right in front of the BT DPs so access wasn’t brilliant.

The modems used back then were mostly Micom-Borer, but there were some others ‘installed’ on that shelving too. We’ll get back to these in subsequent posts, oh yes.

[1] In the bizarre twists of fate that life throws at you, this is now my office, which I share with five other people. It’s been refurbished slightly, but there is still evidence of it’s former use. There’s a few 100-pair DPs on the wall, a number of the original telephone points, that the modems used to connect to, are still there, and there’s a BT 2M unit still attached to the wall. It still has a raised floor and I suspect that are a number of old coils of cable still lurking under there.

1988 was a strange year for me. I spilt up with my wife, I’d made an inter-departmental transfer within the company I was previously working for, started a new job, obviously,  and also threw off, outwardly at least, the shackles of being a Punk. This latter event saw me actually going to work in in a shirt and tie, and that probably was the most traumatic event of 1998, TBH;-) Note that I said outwardly there. Once a Punk, always a Punk, IMV!

So, I start this job as a Communications Technician. Up I stroll in my white shirt, red tie, smart trousers and DMs (natch) , I get my own desk, my own phone (on the desk, no such thing as a mobile in those days!)  and everything. There’s five of us crammed into a rather small office, all but one of us a newbie and the current encumbant, Adrian, turns to us and says, ‘Bloody hell, four of you. What am I supposed to do with you all?’. Or words to that effect;-)  Having got to know Adrian over the years, I do know he would have said considerably more than that as he could talk. And talk. And talk. Over the first few months, we got to learn that if we wanted to waste an hour or two, we just get Adrian talking about, well, almost anything, and he’d give us our wish!

So, I start this job as a Communications Technician. It would be no word of a lie if I said that I knew nothing about comms. Nowt, nada, zilch! I didn’t even know what a modem was, for a start. RS.232? Wassat? Co-ax? It’s what you used to plug in your TV to the aerial weren’t it? As for anything remotely concerned with an IBM mainframe, forget it! All this, and more, I would learn over the next few months, and years.

So, I start this job as a Communications Technician and it would be pretty accurate to say that I really lucked into this role. For this I must really thank, from the bottom of my DMs, the two chaps that interviewed me and offered me the opportunity, believing that I could actually do the work required of me, despite my total lack of experience. I must also give Ade a huge back-slap and high-five for everything he taught me over the years. Good on yer mate, and if I do ever catch up with you again, the first fifty-odd pints are on me:-)

Anyway, enough waffle[1], let’s get to the nitty gritty.

[1] Sorry, I don’t why I said that. There will definitely be more waffle.