Spending the last 24+ years as an engineer on Enterprise systems from AT&T/Lucent Technologies/Avaya Communication, this is almost the exact same procedures that we used on the legacy PBX's from the AT&T/Lucent days. The circuit packs were the same dimensions, and even with similar TN identifiers. While even in a duplex system, most subscriber and trunk line cards could be done "hot", although you would still place them Out of Service from the console. The only time you powered down a shelf was when you were in the processor complex itself (and even then they had a few exceptions, particularly in a duplex system). Reportedly the AT&T 5ESS and the System 75/Definity G3 Enterprise platforms came from the same engineers, so they had a lot of these things in common. In all the years I've worked on them, I never had ESD destroy a card, and never bent a pin, so consider me lucky (and well versed in the handling procedures).
Nortel did the same thing. A Meridian SL-100/CS2100 is a rebadged DMS-100. AT&T sold a few 5ESS for large PBX deployments, where I used to work we had a 5ESS from the 1980s until the late-2000s. It used to provide ISDN data networking until Ethernet took over in the mid-90s.
@@straightpipediesel Re bent pins, was it just consumer systems that NT used card-edge on? I thought I remembered seeing most of the accessories for MDC using card-edge as well.
I wish I worked in that as well inside of a Windowless Building. I graduated last year with an IT Degree with a Minor in Criminal Justice (BA)… if only.
@@NortelGeek yeah, it must have just been the lower end. Small Meridian cards are of similar size/shape to DMS cards and use pin connectors very similar to the AT&T ones.
This, this is a major function of my Job today here in Washington. Replacing 5ESS packs. I recognize the TN335 LUCHBD pack he was replacing in a Line Unit.
I worked at the WE/AT&T/Lucent manufacturing plant from 1976 to 2002 where we made the 5ESS switch. When the video started the first thing I thought was why is the pack not in an anti static bag and where is his his wrist strap. That was a big no no when handling any product or components in the plant. The video brought back a lot of memories.
Back in the electromechanical days of telephony the #1 ESS switch was looked at as a job threat. Our CO went from 45 technicians to 3 a few years after cutover to ESS. Two people were needed to run cross connect jumpers on the main frame.
I worked at Clevoh45 and Clevoh62. Better known as the Glenville and Cleveland Main CO. I started as an Apparatusman at the Glenville in 1968. In one year I was promoted to Central Office Technician. In the sixties the draft was taking young men for Vietnam, so I was promoted rapidly. I had already served in the Air Force.
@@ConnectionsMuseum I worked at the Clevoh45 and Clevoh62. Glenville and Cleveland Main. I started as an Apparatusman in 1968 and was promoted to Central Office Technician in one year. At the time the draft was taking most young men for Vietnam. I had already served in the Air Force.
I've never seen a 5E switch that lists the CLEI/HECI on the pack list. Just the apparatus code and location. This video is pretty old. No telling what generic they were running. I never knew what that RST/ROS switch was. Nobody ever uses that, including the center. ESD practices are always prudent but I rarely see anyone follow them in twenty years of central office work. 5E circuit packs are a lot more rugged and robust than this video would have you believe. We are now in the process of consolidating and ultimately removing the 5E switches. Consolidation because you can't get parts anymore. After removal, a huge roomful of 5E cabinets can be replaced with a few racks of GenBand gear about the size of a couple refrigerators. I like working on the 5E. I'll miss it when it is gone.
Indeed. Those things routinely survive lightning events. Someone touching it isn't likely to hurt anything. The ROS switch is completely unnecessary if you've taken the card out-of-service from the terminal. (or, ya' know, it's already OOS because it's broken.) Powering down a slot is absolutely necessary - if you short a pin with the power on, you could do some serious damage. I recall our tests of a softswitch... 7U could replace a small house sized 5E. (of course, it's all digital. all the POTS termination gear would still take up a goodly bit of space. 100,000 lines is still 100,000 lines, 'tho in a modern world, the analog termination is out in the field.)
Wow these circuit packs are a lot like the Definity’s. I also see now why early definity circuit packs have a recess on the top cover, it is for that locking bar. I assume early system 75s had a locking bar like that.
The only thing I guessed that was done wrong on the first clip was he was not grounded against static discharge and he was touching the circuit board. I didn’t know anything about shutting down the unit after placing it out of service and checking to see if the system automatically placed the unit out of service. I never worked in an exchange so I had no idea but it all makes sense.
If its like the Enterprise systems, those packs went back for repair (each of those packs are thousands of dollars, so it was much more economical to return for repair compared to today's "throw away" technology - even today I still see used Enterprise System packs going for between $1,000 and $2,000 - that probably sold new for $6,000).
@@mwjones71 Indeed. Back in the 90s and before, it was not unusual to order new gear and it included a board that was "remanufactured". So you might order a minicomputer and a memory board came with a sticker stating it had been previously in use... same warranty and price as new. I think IBM did this a ton too in their midrange and mainframe business.
I'm watching this again and a thought just crossed my mind--I realize that space was an issue and to ATT, every millimeter counted, however, why didn't they just put the packs that were most-replaced in plastic clamshells? As far as bent pins, they could have just used several rows of card-edge connectors (Wafa-jacks).
The person did not explain what TLP stood for. Trouble locating procedure. That would be the print out, that would be generated in the event of a failure of sorts. The TLP print out would give you a sequential number of circuit packs that are in question, and you would follow that procedure, starting with the most likely, to the least likely. That does not necessarily mean that you will replace the circuit pack that failed, it could be in the back of the frame or where the pins are somebody pressed up against it or a piece of loose material fell between and shorted something could be intermittent, or possibly a heart failure, that's where knowing how to use an oscilloscope came in, and running loops and setting up the proper sink to see what was going on, possibly in need of a microscope to see the pins the in the back plane side, to can see if a piece of loose welding material eventually broke loose and fell down, Etc.
Yes. THE UNIX(tm)... AT&T System V UNIX(tm). But there's a lot more going on than just the OS you can easily see boot, and get a CLI from. (note: these are the sort of systems that boot only once in their entire existence.)
I've worked in places (not phone switch places) where humidity was pretty high and nobody every saw an ESD problem. Of course, we still took precautions
Why isn't he wearing, a ground wrist strap? When I work number four and number five SS, it was mandatory to wear a ground wrist strap when you remove any circuit pack. Touching the packs with your bare fingers, static electricity you could destroy a circuit pack that might be worth, $10,000 or more. At the time when I was working in both four and five ESS, if you did not use a wrist wrap, you could get as much as 3-day suspension without pay. I'm not sure if that was nationally, but in the New York metropolitan area, that was the rule.
I worked at Digital Equipment Corporation and ESD safe handling procedures were constantly drummed into our heads. I was surprised to see this instructional video showing no reguard for ESD handling of circuit cards. The man walks with a card in his hand touching his shirt. Puts paper next to removed circuit card. I don't see any ESD foot straps, wrist strap, ESD smock. I guess AT&T didn't see this as a problem. At DEC we were told that static discharge can zing a board and cause it to fail later if it doesn't cause it to fail outright.
@@ennexthefox I worked for AT&T formerly Western Electric on number for number 5 ESS you were required to wear a wrist strap at all times. No exceptions
![[3ESS] Introduction and Tour](/img/n.gif)
Spending the last 24+ years as an engineer on Enterprise systems from AT&T/Lucent Technologies/Avaya Communication, this is almost the exact same procedures that we used on the legacy PBX's from the AT&T/Lucent days.
The circuit packs were the same dimensions, and even with similar TN identifiers. While even in a duplex system, most subscriber and trunk line cards could be done "hot", although you would still place them Out of Service from the console. The only time you powered down a shelf was when you were in the processor complex itself (and even then they had a few exceptions, particularly in a duplex system).
Reportedly the AT&T 5ESS and the System 75/Definity G3 Enterprise platforms came from the same engineers, so they had a lot of these things in common.
In all the years I've worked on them, I never had ESD destroy a card, and never bent a pin, so consider me lucky (and well versed in the handling procedures).
Nortel did the same thing. A Meridian SL-100/CS2100 is a rebadged DMS-100. AT&T sold a few 5ESS for large PBX deployments, where I used to work we had a 5ESS from the 1980s until the late-2000s. It used to provide ISDN data networking until Ethernet took over in the mid-90s.
@@straightpipediesel Re bent pins, was it just consumer systems that NT used card-edge on? I thought I remembered seeing most of the accessories for MDC using card-edge as well.
I wish I worked in that as well inside of a Windowless Building. I graduated last year with an IT Degree with a Minor in Criminal Justice (BA)… if only.
@@NortelGeek yeah, it must have just been the lower end. Small Meridian cards are of similar size/shape to DMS cards and use pin connectors very similar to the AT&T ones.
I am so glad that I now know how to replace a turbo encabulator.
Just remember to disengage the drawn-reciprocation dingle arm first. I made that mistake. Never again.
This, this is a major function of my Job today here in Washington. Replacing 5ESS packs. I recognize the TN335 LUCHBD pack he was replacing in a Line Unit.
I worked at the WE/AT&T/Lucent manufacturing plant from 1976 to 2002 where we made the 5ESS switch. When the video started the first thing I thought was why is the pack not in an anti static bag and where is his his wrist strap. That was a big no no when handling any product or components in the plant. The video brought back a lot of memories.
Back in the electromechanical days of telephony the #1 ESS switch was looked at as a job threat. Our CO went from 45 technicians to 3 a few years after cutover to ESS. Two people were needed to run cross connect jumpers on the main frame.
What CO did you work in?
I worked at Clevoh45 and Clevoh62. Better known as the Glenville and Cleveland Main CO. I started as an Apparatusman at the Glenville in 1968. In one year I was promoted to Central Office Technician. In the sixties the draft was taking young men for Vietnam, so I was promoted rapidly. I had already served in the Air Force.
@@ConnectionsMuseum I worked at the Clevoh45 and Clevoh62. Glenville and Cleveland Main. I started as an Apparatusman in 1968 and was promoted to Central Office Technician in one year. At the time the draft was taking most young men for Vietnam. I had already served in the Air Force.
@@calbob750 Thank you for your service in both capacities.
Brings back old memories as an engineer at factory where we made 5ESS.
I've never seen a 5E switch that lists the CLEI/HECI on the pack list. Just the apparatus code and location. This video is pretty old. No telling what generic they were running. I never knew what that RST/ROS switch was. Nobody ever uses that, including the center. ESD practices are always prudent but I rarely see anyone follow them in twenty years of central office work. 5E circuit packs are a lot more rugged and robust than this video would have you believe. We are now in the process of consolidating and ultimately removing the 5E switches. Consolidation because you can't get parts anymore. After removal, a huge roomful of 5E cabinets can be replaced with a few racks of GenBand gear about the size of a couple refrigerators. I like working on the 5E. I'll miss it when it is gone.
Indeed. Those things routinely survive lightning events. Someone touching it isn't likely to hurt anything. The ROS switch is completely unnecessary if you've taken the card out-of-service from the terminal. (or, ya' know, it's already OOS because it's broken.) Powering down a slot is absolutely necessary - if you short a pin with the power on, you could do some serious damage.
I recall our tests of a softswitch... 7U could replace a small house sized 5E. (of course, it's all digital. all the POTS termination gear would still take up a goodly bit of space. 100,000 lines is still 100,000 lines, 'tho in a modern world, the analog termination is out in the field.)
Wow these circuit packs are a lot like the Definity’s. I also see now why early definity circuit packs have a recess on the top cover, it is for that locking bar. I assume early system 75s had a locking bar like that.
Who is the talent? He did all sorts of industrial films of the era.
Don't you dare pissoff circuit replacement dad,
Circuit replacement dad is very very disappointed in you...
"... and for goshsakes, put your tools back when you're done with them. I'm tired of having to go looking for the screwdriver."
the music in this short goes way harder than it needs to
The only thing I guessed that was done wrong on the first clip was he was not grounded against static discharge and he was touching the circuit board. I didn’t know anything about shutting down the unit after placing it out of service and checking to see if the system automatically placed the unit out of service. I never worked in an exchange so I had no idea but it all makes sense.
PROTECT THE SWITCH!
I wonder what they did with the old circuit packs. Did they send them off for repairs or did they dispose of them ?
If its like the Enterprise systems, those packs went back for repair (each of those packs are thousands of dollars, so it was much more economical to return for repair compared to today's "throw away" technology - even today I still see used Enterprise System packs going for between $1,000 and $2,000 - that probably sold new for $6,000).
@@mwjones71 Indeed. Back in the 90s and before, it was not unusual to order new gear and it included a board that was "remanufactured". So you might order a minicomputer and a memory board came with a sticker stating it had been previously in use... same warranty and price as new. I think IBM did this a ton too in their midrange and mainframe business.
I think everything went back to Western.
@@NortelGeek I have numerous packs from Lisle Illinois. Not really supposed to lol. The 5ESS was taken out of service in Jan 2019.
@@finaltransconfigurat Holy smokes! Lol... I won't tell. Which ones do you have if I may ask? Do you know what switch they replaced the 5E with?
I'm watching this again and a thought just crossed my mind--I realize that space was an issue and to ATT, every millimeter counted, however, why didn't they just put the packs that were most-replaced in plastic clamshells? As far as bent pins, they could have just used several rows of card-edge connectors (Wafa-jacks).
Card edge connectors were huge, bulky things back then. Even today, they're often the source of issues - dirty / bad connections.
The person did not explain what TLP stood for. Trouble locating procedure. That would be the print out, that would be generated in the event of a failure of sorts. The TLP print out would give you a sequential number of circuit packs that are in question, and you would follow that procedure, starting with the most likely, to the least likely. That does not necessarily mean that you will replace the circuit pack that failed, it could be in the back of the frame or where the pins are somebody pressed up against it or a piece of loose material fell between and shorted something could be intermittent, or possibly a heart failure, that's where knowing how to use an oscilloscope came in, and running loops and setting up the proper sink to see what was going on, possibly in need of a microscope to see the pins the in the back plane side, to can see if a piece of loose welding material eventually broke loose and fell down, Etc.
Was this powered by UNIX?
Yes and no. They ran DMERT which was like a blend of Unix and a real-time operating system built for high availability.
Yes. THE UNIX(tm)... AT&T System V UNIX(tm). But there's a lot more going on than just the OS you can easily see boot, and get a CLI from. (note: these are the sort of systems that boot only once in their entire existence.)
Hey, where is the wrist ground strap?😳
Keep watching.
@@hmbpnz 👍😊
Notice how there are no ESD precautions. No wonder most of the circuit packs that I received as maintenance spares where defective.
I've worked in places (not phone switch places) where humidity was pretty high and nobody every saw an ESD problem. Of course, we still took precautions
Why isn't he wearing, a ground wrist strap? When I work number four and number five SS, it was mandatory to wear a ground wrist strap when you remove any circuit pack. Touching the packs with your bare fingers, static electricity you could destroy a circuit pack that might be worth, $10,000 or more. At the time when I was working in both four and five ESS, if you did not use a wrist wrap, you could get as much as 3-day suspension without pay. I'm not sure if that was nationally, but in the New York metropolitan area, that was the rule.
They get into that. He made a mistake. This is a high-tech Goofus and Gallant example.
54 and out the door!
Is the guy who made all those mistakes still on unemployment?
And then it all became irrelevant as the world moved from circuit switching to packet switching.
Wrist straps are overrated. Never used them in 30 years and never destroyed hardware.
I worked at Digital Equipment Corporation and ESD safe handling procedures were constantly drummed into our heads. I was surprised to see this instructional video showing no reguard for ESD handling of circuit cards. The man walks with a card in his hand touching his shirt. Puts paper next to removed circuit card. I don't see any ESD foot straps, wrist strap, ESD smock. I guess AT&T didn't see this as a problem. At DEC we were told that static discharge can zing a board and cause it to fail later if it doesn't cause it to fail outright.
Did you watch the whole video? This was the "don't do it this way" part of the video.
The first part of the video is showing you what not to do
@@ennexthefox I worked for AT&T formerly Western Electric on number for number 5 ESS you were required to wear a wrist strap at all times. No exceptions
@@ennexthefox Yeah, clearly he didn't watch the whole video.
Of COURSE we all know how to replace a circuit pack, don’t be ridiculous.