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)
This is a Spanish Ericsson DIAmuX Access Node (AN) centrally located in the Local Exchange (LE). The racks are hinged so that the sub-racks can be swung out giving access to the rear of the shelves.
The Access 300 Diamux 500 is designed for generic, flexible and integrated access and small digital cross connect
applications. It is based on flexible system design, well suited to meet demanding requirements of a modern access network.
The Diamux 500 is intended to serve as a large access node handling traffic from multiple-service 2 Mbps lines and
collecting POTS, ISDN and Leased Line services etc. into single-service aggregate lines.
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.
Picture source: My own library.
This is an Ericsson AGM415 PSTN line card from the DIAmuX system.
I am trying to source the Resistor Networks for AGM415.
Can you help?
Interoperability Testing (IOT)
Over the last few years I have performed many Multi-Vendor projects that have required Interoperability testing, or IOT testing as it is also know as. In a Multi-Vendor environment it doesn't matter how thorough the project solution is planned when it comes to connecting Multi-Vendor products together there are, in 9 cases out of ten, "Interoperability" problems. Here are a few thoughts from four different technology areas that I have experienced;
Radio Access Network IOT
With the strength of OEMs such as China`s Huawei increasing each year it is common for the most loyal of customers to introduce other vendors products into their networks. When this happens they perform Multi-Vendor Integration projects and part of the project is; IOT testing.
With RAN products such as the 3G WCDMA Radio Network Controllers (RNC) the IOT testing is concerned with the handover of traffic from one vendors RNC to the other. It is usual for both OEMs to have a project team and in several cases although we are integrating towards each other the customer will instruct us that we cannot communicate (speak) to each other! Understanding the frustrations of the engineers a good Project Manager will accidentally bump into the other team in the canteen.
Access Network IOT
Unlike legacy PSTN switches which commonly have command line interfaces the Access network nodes tend to have more of a Graphical User Interface. Within these GUI (gooey) interfaces there are frequently selectable node types that the user can click on or select so that the node will auto configure the interface to the switch type selected. For example; the Alcatel Litespan Access node has a pre-configured S12 interface. This makes life easy for the O&M or Integration engineer. Point it towards an MV environment however and you could end up learning how to use a protocol analyser.
PSTN Network IOT
PSTN interoperability testing tests whether the V5 protocol can function correctly with the intended target node(s) interface environment, i.e, the target node(s) interface hardware, software or firmware.
Usually there are less than a dozen individual parameters that will need setting (matching) on either side of a V5.x protocol link. The most well known being the Variant ID, Link ID, etc (ref. wiki).
Where specified, pre-agreed test cases require that combinations of the intended target nodes environment is configured and available to the test team. The test case results are normally measured or compared with the existing interface(s) as part of the acceptance criteria.
Multi Vendor Repair Capability & IOT
Planning a "new repair capability" development project from scratch is one thing. It always seems to work on paper. Realising a "working" new repair capability from scratch is another thing all together.
In all cases the solution needs to achieve a level of working operation to enable the repair technicians to repair down to component level.
Interoperability can be a tough phase during the development.
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.
Above: Bourns resistor networks with U.S.PAT.NO.5,097,247 solder fuses. Patent here. Note the corrosion along the central track.
Above: Resistor packs manufactured by Welwyn. Solder fused. Note the black corrosion of the ceramic & substrate.
The above pictures are of resistor networks (a.k.a. resistor packs) from the Ericsson DIAmuX AGM415 card. These resistors are using what is called Heat Actuated Fuse Apparatus by Solder Link. Normal working resistance is 20.2 ohms.
This type of fuse doesn't hold out until it blows at over current. Instead it will blow at a pre-determined temperature (as temperature is a better indicator) of imminent damage than a current regulated fuse.
Although it is the heat of high current that blows all fuses a clear explanation of Heat Actuated Fusing is in U.S.PAT.NO.5,097,247 here
Both of these resistors are from a DIAmuX AGM415 line card. The cards have failed and been sent for repair.
I am trying to source & procure these components. Qty needed: 5000.
Image source: My own library.
This is an Ericsson Line Circuit Test card. The LCT card sits in the Line Switch Module shelf (LSM). There is one LCT per shelf and they are all connected up with an 8 pair cable (two quarter plugs in a half plug cover) making a half plug bus.
Each half plug piggy-backs onto the next. The end of the bus is terminated with a resistor plug that itself piggy-backs onto the end of the bus.
Although manufactured in year 2000 this is a very old card design of AXE10 BYB202 more reminiscent of the 80s.
Function: Subscriber Line Test.
Product code: ROF 137 1533/1 R2C
Manufacture date: 2000 Week 37.
Card name: LCT (its actually on the card as LTC)