The above picture shows rows of Line Switch Modules (LSM's) neatly lined up awaiting their fate. This scene reminds me of what it looked like when we were installing the AXE switches. Sadly, this once busy switch is now being dismantled with its subscribers and their traffic already having been migrated to a Next Generation (Voice over IP) based node. The above AXE10 was a fantastic switch and carried traffic in service for over 20 years without any outages.
This is an alarm panel from the 80's and 90's generations of BYB202 AXE10. Easy to interperate with A1 and A2 class for the APZ (processor), APT (switching), POWer and EXTernal alarms.
O1 and O2 are Observation alarm classes.
ATT is for ATTendance activated by command by AXE personnel when on site (site attendance).
The white gas mask shaped things are acually speakers and beep when there is an alarm.
TYN and MAN are the names of the sites this panel serves.
Twenty four years to the day since I have been around AXE10. Here I am standing next to an in service APZ211*11. If I could live my life over I would join Ericsson and become an AXE10 engineer again. Two of my good friends (now passed the great divide) were part of the team that installed and commissioned this site in 1990. They done a fantastic job.
Work around enough AXE's and you will come across one of these units. These are the typical airconditioner units that are used in an exchange room containing an Ericsson AXE10 BYB202. They are made by Weatherite Building Services Ltd who have thier head office in Aldridge near Walsall.
The control panel has controls catogories for the Supply fan, Condenser Fan, Compressor #1, Compressor #2, Cooling and Heating.
IOG 11 belongs to what is called an SP-based IO System.
SP is an abbreviation for Support Processor. It is the separate processor that control the IO system functions, for example. the hard disks, optical disks, floppy disks and all the Alpha numemric (AT) terminals, later called Local Craft Terminals (LCT's) and all other communication links between the AXE and humans or other computer systems. i.e. X25/V36 protocol links.
Several variants of the SP-based IO Systems existed including IOG 11A, IOG 11B, IOG 11C, IOG 11B5, IOG 11C5 and IOMC.
This is an icon of all classical PSTN telephone exchanges and is where I started my telecom career as a British Telecom T2B jumpering MDF's.
These white plastic blocks are the more modern blocks that were used for digital switching (System X, AXE10..)
The older metal and bakerlite blocks served the Strowger,
Crossbar and TXE switches. Upon exchange transfer we would cut over the traffic from the old MDF onto these new white blocked MDF's.
During my 10 years on BT Public Systems we used these keyboards to communicate with the AXE10 switches. It was on after the introduction of Windows 98 that we using laptops and desktops to talk to the switch. The tandberg terminal were so called dumb terminals. (A terminal that depends on the host computer for its processing power is called a dumb terminal or thin client)
The card we are looking at here (labeled RP64) is an RP4-H card. RP4 stands for Regional Processor Generation 4 being a newer version of the traditional AXE10 BYB202 Regional Processor.
The primary benefit for RP4 is that it is co-located in a subrack with the Extension Modules (EM's) that it controls. In AXE10 RP's control EM's and EM's control devices.
The RP4 is only found in BYB501 / AXE810 generation of AXE10 and does away with parallel buses, instead having a serial bus cable as seen above RPB S/O and RPB S/I. (Serial out and Serial in)
These buses are actually cables that are cabled directly back to the Central Processor (APZ212*33 in the above case)
The above picture shows the hardware architecture of the generic device magazine, also known as a subrack. As I said above, in AXE10, RP's control EM's and EM's control devices which can be clearly seen in the picture.
CP controls RP4 which controls the EM's which contain (and control) devices. A device can be any entity that provides a service such as a line circuit (LIC) on a line board (LIB) for instance. An example of a LIB in AXE10 is ROF 137 4442/1 LIC12.
This is a microcomputer unit from the Ericsson ROF 137 7852/1 R4B SLCT3 card. Card manufacture date is 1997 week 22.
Chip manufacturer: Motorola.
Category: 8-bit HCMOS microcomputer unit.
Introduction Technology: high-speed and low-power MCU; enhanced 16-bit timer system with four-stage programmable prescaler; power saving STOP and WAIT modes; serial peripheral interface (SPI); 256 bytes of static RAM; eight-channel 8-Bit A/D converter
Max. clock frequency: 2 MHz
This card now labeled ROF 137 1533/1 R2B/A LTC has 99W01 as its manufacturing date but a side label shows the original manufacture
date printed F3 8412 (1984 Week12 from factory F3).
I am guessing that this card started out life as an R2B and was sent back to Ericsson (or to a 3rd party) on 1999W01for modification & upgrade to R2B/A.
1984 Week12 is sometime from Monday 19th to Sunday 25th 1984.
If we decide the card was manufactured on the Monday then the approximate duration calculation results are;
From and including: Monday, 19 March 1984
To and including: Friday, 9 September 2011
Is 10,036 days from the start date to the end date, end date included.
Or 27 years, 5 months, 22 days including the end date
Alternative time units
10,036 days can be converted to one of these units:
1433 weeks (rounded down)
Yep, AXE10 is getting old!... but its still in service. The above card went down with worn out relays. It was repaired and sent back out to its site in Denmark. I hope shes in service for another 27 years!
Duration calculation by: http://www.timeanddate.com/
This is one of the old Tandberg (VT100) terminals that we used to use in order to talk to the AXE10 BYB202 PSTN switches. System X PSTN switches also used these terminals. It is what they call a dumb terminal.
We also would have had a keyboard (with a card reader attached to it) that we could swipe a pass card through so that we could access the switch.
We stopped using Tandbergs soon after Windows98 came in.
Above pictures: From my own archives.
The Ericsson AXE10 system uses address plugs that directly plug onto the cards in order to give the unit an address. The above address plug RNV 99103/20 R1A is typically used to address the Regional Processor magazines. RNV99103 also is used to address the EMRP (Extension Module Regional Processor) cards of the LSM magazines as shown in the below picture.
Product function: Address plug.
Product code: RNV99103/20.
Quarter plug: RNV304002.
Manufactured: 1998 Week 23.
Above: An EMRP card from an LSM shelf of an Ericsson RSS EMG addressed as EM-0.
EMRP: Extension Module Regional Processor.
LSM: Line Switch Module.
RSS: Remote Subscriber Stage.
EMG: Extension Module Group.
EM: Extension Module.
Picture source: My own archive.
The Digital Local Exchange (DLE) is the same as an Ericsson AXE10 Local Host Exchange and like the Ericsson Local Host the DLE connects to the concentrators (CONCs) via a 2Mbit PCM link running V5 protocols. The Ericsson equivalent of a CONC is a Remote Subscriber Stage (RSS).
It is in the CONC that the line cards are placed.
In order to route calls to different DLEs or DMSUs all traffic is quantanised (i.e analogue to digital converted speech placed in to Time Slots and built into Time Frames) which are placed on to the 2Mbit 30 channel PCM COAX highways and sent out from the Concentrator Units towards the Time Switches. In Ericsson AXE10 world this can be written as ETB to ETC via 2Mbit COAX using V5.2 and on to TSM/SPM.
Thereafter it is routed using the B-number analysis and placed onto the correct Routing Case depending on the destination of the call.
The above switch is one of the most robust switches I have ever experienced as it has been moved at least 6 times during its (to date) 30 years of service.
This is an Ericsson BYB501 IOG20BP from the Arnhem hybrid site.The IOG20 BP was a two shelf configuration meaning that the A-side node was on one shelf (top) and the B-side node below it.
The IOG20 came in several variants; IOG20A, IOG20B, IOG20C, IOG20BP. There was also IOG20M.
A- the first variant (model) of IOG20 on early BYB501 (extremely rare).
B- the improved variant of IOG20A. All serial buses.
BP- is for parallel as this IOG version could terminate RP buses from BYB202 parallel buses as well as BYB501 serial buses.
C is the compact variant which has both A&B-side in the same shelf with all serial buses.
To be fair- all IOG20 could be adapted to handle parallel buses.
They were superseded by the APG40 running on a Windows platform.
This is the APZ212*30 from the Vodafone Arnhem site. This was a BYB202 and BYB501 hybrid switch that was decommissioned in January 2008.
APZ212*30 (pronounced APZ two twelve thirty) came in two different versions, the APZ 212*30 and the APZ 212*33. These were the configurations that were available.
APZ 212 30 IPN Not Adapted
ROJ 212 228/3 R1C IPU
ROJ 212 229/2 R1G SPU
ROJ 212 227/3 R1A POWC
ROJ 212 206/1 R10C MAU
APZ 212 30 IPN Adapted
ROJ 212 233/1 R1C IPU
ROJ 212 234/1 R1F SPU
ROJ 212 239/1 R2E POWC
ROJ 212 206/2 R1C MAU
APZ 212 33 IPN Not Adapted
ROJ 212 236/2 R3B/A IPU
ROJ 212 229/2 R1G SPU
ROJ 212 232/1 R2E POWC
ROJ 212 206/1 R10C MAU
APZ 212 33 IPN Adapted
ROJ 212 238/1 R2E IPU
ROJ 212 234/1 R1F SPU
ROJ 212 232/1 R2E POWC
ROJ 212 206/2 R1C MAU
I loved working on these processors. They were the best in class during their day and I have a lot of information available about these processors.
The 2-20, as it was called, is a pair of CP racks that work in parallel synchronous and at any one time either the A-side rack or the B-side rack would be the Executive side (handling the traffic) and the other side would be in active standby ready to take the traffic should the Executive side fail.It was easy to see who was who as there are indicator lights at the top of each rack. I would be surprised if there are many (or any) of these still in service? If you know of one please let me know.Top Shelf: Fans for cooling.
Second shelf down: the CPU shelf itself.
Third shelf down: RP bus magazine and tall blanking plate where the maintenance unit (MAU) would be if this was a B-side processor rack.
Bottom shelf: RP bus magazine.
The little green light on top of the rack indicates that this rack is the Executive processor, the processor that is primarily handling the traffic being switched at the time of taking this picture. The blanking plates were always used to increase the cooling efficiency.
Fully under floor air conditioned AXE10 BYB501GSM Main Switching Centre (MSC) CORE with BYB202 APZ212*20 processor that I commissioned in the Middle East during 1999.
The customer commenced full commercial operations in the same year and by 2001 had over 1,000,000 mobile subscribers.
The above picture was taken when I was called in one weekend to fix
an ETC5 card that had gone faulty.
This is a typical Ericsson control room from the late nineties. Earlier control rooms are easily distiguishabe as they used Tandberg (dumb) terminals for switch commuications however here we have pc terminals using windows 98. Each switch that was installed would have had a room like this and usually with the glass screen so that one could see the switch. We also enjoyed using laptops which made our life much easier having all of our software tools at our fingertips wherever we went.