Why did I just spend 40 minutes watching a video about some archaic switch/button? .. I haven't got the faintest idea why.. But it was well narrated and oddly interesting
Part of me knows that this information will be vital.... for me to be the guy who knows way to much about the a4/v2 /?R1? rocket. so thanks for enabling me to be "That Guy"
Very excellent explanation. Before 1937, Lockheed utilized a similar switch called the "wieght on wheels" switch to disable the electric landing gear actuator motor so the gear could not be retracted before the airplane was flying. The same concept is incorporated into modern retractable landing systems today. The same weight on wheels method is used to enable the spoilers and thrust reversers on many types.
There's a lot of similarities between A7Y and weight-on-wheels sensors, as it is simply a "weight-on-rocket" sensor. I wonder whether or not it was tuned more to be accurate in the release, and in the microsecond range, while weight-on-wheels might be good within multiple microseconds, or a larger fraction of a second, and for loading as well as release. These seem to accomplish the same goal, but with very different constraints. I know some German engineers designed their parts at the time with unnecessary accuracy, so it could very well be that these were also designed with measuring loading forces just as accurately as the releasing force. Would be interesting to know, as with the raw data for the response time.
Great video! Well done. Thanks Robert. Electrical Engineer here. I can see that in the modern world a LOT of this design could be done today with a microcontroller and software. I appreciate the deep dive into this 1940s design with relays, motors, gears & cams driving contacts in sequence.
I would to have the V2 electric schematic diagram!. It's really interesting to see the German's designing choices at that time. Thanks for this really good research work!.
Around 13 minutes....A simplified circuit diagram ..... this man produces extraordinary support materials like rabbits out of a hat! Another wonderful and strangely captivating episode of this magnificent series.
A very interesting look at part of the takeoff circuitry of the V2 / A4 and the all important switch which triggers the systems to begin a chain of events because the rocket has left the pad and is on its way. Thanks so much for sharing.
Great video. I wonder what effect G forces had on the various relays during flight. I would imagine they were oriented on the missile to reduce the influence of these forces. The engineers must have put relays designed for telephone service through rigorous testing.
You should use automatic washing machine's control unit (tiny electric geared program motor with drum of cams/contacts) for better illustration for your A4 electric model. Thanks a lot, it was really impressive! +1
Best video i've seen on this subject!!.A few years ago i built and flew several solid powered models of the v2.I know it sounds strange but pressing the launch button gave a strange excitement!!
There was a term in German "zwangsgeführte federunterstützte schaltmechanik" (force-guided spring-assisted switching mechanism) when you where looking for push buttons in electronics mail order companies. I guess this was meaning the same kind of switch-characteristcs though I can't find this term now anymore. I was using that kind of switch for my self-wound starting transformer. The same features microswitches have as well I suppose.
Missed out on the variable resistors Carbon film or swept wirewound. The switch reminds me of pre-war ceramic light switches, lot of brass pivot points, fast , for early town DC supplies before Grid Enforcement.
Admiring the beautifully written piece of prose there at the end clearly defining the 'mission statement' for your presentations here. Their poignancy most correct...etc. The irony then of Herr Von Braun's procurement by the American Authorities for 'peacetime scientific advancement'. Nut's to what he and cronies did. Powerful stuff. Moving On. As we all had to...apparently. Thank you for your illustrations. Simply fascinating insight.
Hi there, fantastic video, very informative. In what way do you think a V2 could have been sabotaged without detection during pre-launch tests? Thank you.
And to think that all that incredible Engineering and complex electronics would, after a short flight time be blown to smithereens as the Warhead contacts it's Target. I cannot help but wonder what these things cost to build? Of course the same holds true for modern equivalence of the V2. ICBM at the top end of the scale and possibly air to air missiles at the bottom end, they all cost millions to develop and more millions to build. All for man to wreak destruction on his fellow man, and along the way make huge profits for the armaments industry.
The way this electromechanical system works, with the central timer motor connected to various relays and switches, is exactly how an old pinball machine keeps score, adds bonuses and counts balls etc. Very clever.
Congratulations for this video about the technology of the A4-V2. In this and other videos, he presented schemes. Is there any way to make them available to those of us who are fascinated by rocket technology?
The switch actuation is called snap action, and is commonly used in instrumentation today. All of this including the drum timer could be done with a simply designed PLC nowadays.
A well researched, well presented presentation of the A-72 launch switch. Thank you very much for the effort to make a complicated sequence of events so easy to follow.
With all of the knowledge you have shared with your videos, then viewing the old launch movie clips, one can understand and grasp what is taking place and when. Excellent production start to finish on all of your videos, thanks from Ohio in the USA.
Id love to see a new video on the way they designed the bell of the rocket motor, and how they integrated cooling into the system that you mentioned in the video about the injector pots.
Blueprints always engage me, and the amount of copies, must make reproduction so expensive. Modern wide base photocopying is so cheap (so many rehashes/mods :-)
Amazing video! Cant wait for more detalied videos (turbopump part 2 🤔😉) Did you make the model in Sweden? Those batteries are from Biltema and Kjell & Co. Swedish stores 🙂.
Question Sir, Does your V2 display visit any of the Civilian Museums.... and does your Meade still work ? Followed your diagrams and interconnection fine, but since so much sabotage was carried out, an external DC Sw(A72). would be very tempting. The pre-testing (missing) would be most important for the A7y relay (I Prefer ASEA relays, but not robust for lorries) and will not be heard, did the crew use a 'mulitester/dedicated' to discern free movement of both A72 and setting relay A7y. Wiring - Rubber or asbestos insulation ? Love the 'tiny' trembler/bell vibrator 300hz Square A.C. Generator ! The Cam Switcher/programmer if not sealed, it would be delightful to spoil with, a quick contact depression of the thumb, would slow its rotation. Reviewing the Rkt schematic "they really passed over Timer Start Sw" .
As an enthusiast of understanding things of a retrotechnical nature, i found this to be thouroughly engaging. Thanks SO much for taking the time to show us!
Thank,s RobertI did some "Stuff 'as a young person in the USAF.Flt engineer Recip engineer training C-97,,C141A and Finally C-5a run qualified Tf-39 testing .What fascinates me is the seemingly reliance on german technoigy the USAF relies upon for jet engine development not to mention rocketry.For example the sequntial activation caused by A72.The 4 speed box and voltage regulator of the APU starting is almost identical.Having spent so many years of my youth in aviation your presentation has left me wondering about the panic situation that existed during the war to defeat Germany and Japan.It was a terrible cost in human lives.but if it wasn't stopped that next missle would have been tipped with nuclear war head,headed straight for Delancy street in Manhatten
Such detail that explains how technologic advanced the Nazis were in weapons development. Thank God for the allies being able to cut of their supplies in order to suspend further development. Scary to imagine how differently the outcome of the war could have turned. Great detail and visual explanation in all the videos I've watched. Instinctive and intuitive feeling whenever seeing an actual historical video of a launch of the V2 rocket. Will always have a different view when watching any documentary including the V2 in use against the allies. Thank You!!
Thank you so much for a look deep inside the functionality of this amazing rocket. After seeing one in person they have always fascinated me. The resemblance of latter liquid fuel rockets to the father of them all is obvious even after 20 years. Your vid is a gem, the best I've ever seen on this aspect of the control system. Amazing.
Absolutely amazing and how comprehensive these videos and descriptions are. I've learnt more and rehashed my basic knowledge more then most theirtube videos. Thank you for the intuitive information.
There is a complete V2 at White Sands Missile Range's Missile Museum. Much of it is cut-away so you can see the inside construction. I was surprised that much of the circuits were mounted on a plywood stiffener up near the nose.
Love the model of the launch stand, your explanation started to sound like Eric Idles explanation of the attack plans in the sewer system in The Life of Brian.
So well documented and explained - every detail gets attention even the brandings of Siemens and Halske. You might also know that in Dresden in the german military museum is another V2 rocket in the exhibition, but without that launch base I guess. Ihad been there last year before the video had been released otherwise I would have checked that V2 for the switch. A72 in the A4 rocket as it had been called during developement if I remember right. And it was a great idea to show the switch mounted on that rebuilded plate among the debris of that fin / rudder where it belonged. I watched it 3 times to get the full picture right.
Hi and thanks. Don't forget to subscribe if you want to see more like this - and be sure to take a look at Turbopump Part 2, which looks at some surprising physical effects of the pump system on the rocket in flight. ruclips.net/video/CmTxAFY03fU/видео.html Best wishes A&NTV
Thank your amazing deep-dive video! My question is was the control feedback loop using PID or just P (proportional) control? From what I gathered from videos, the control fins and vanes were counteracting the error signal from gyros only in proportion? If so, certainly a deliberate design choice to simplify the missile control unit.
Helmut Hoelzer’s Fully Electronic Analog Computer used in the German V2 (A4) rockets Synopsis: A fully electronic general-purpose analog computer was designed by Helmut Hoelzer, a German electrical engineer and remote-controlled guidance specialist. He and an assistant built the device in 1941 in Peenemunde, Germany, where they were working as part of Werner von Braun’s long-range rocket development team. The computer was based on an electronic integrator and differentiator conceived by Hoelzer in 1935 and first applied to the guidance system of the A-4 rocket.
How did they aligned the rocket to point to the target? I know the Lance rocket had a whole team of land surveyors to properly mark the launch location and calculate the direction to which the rocket should be launched.
The rocket was on a rotating turntable. They knew the compass heading from the launch location to the target and just rotated the rocket so that fin number 1 was pointing toward the target. I'm not sure how they set the range of the rocket though. I'm guessing it was done by setting the rocket to fire for a specific length of time, using the timer system that was started by switch A72 at launch.
@@williamgreen5575 I believe it was the opposite - the velocity was measured (integrating the acceleration through time) and when the preset velocity was reached (which depended on desired range), the engine was cut off.
Hmm. I can relate to the wiring issues more directly than I realise. My first job after leaving school, 1981, was wiring mobile telephone handsets to the transmitter/ receivers and logic boards using a 20 way un-colour coded ribbon cable. This meant all 20 wires, bar one, were coloured grey an looked the same, while having to be hand soldered to their respective contacts in different locations across the unit. This produced a rats nest of grey wires going everywhere. One wire had a red stripe trace, and that was wire No.1. And virtually every handset made had an initial wiring fault because with all the wires so closely bunched, it was just too easy to pick up the wrong wire in the sequence, or mis-count from a re-check to double check the wire count/ termination. Usually any double check, and a double check the double check lead to a different count leading to doubt on the work just done. The best way to check the wiring was to plug it in, but due to costs of components at the time, this was not possible until the unit was installed where it was meant to be, reliably considered, a new and fully functioning unit. It rarely ever was that until the installation engineer plugged it in and now identified by subsystem fault where the likely wiring issue was. But this all added time and frustrated them. Now I can grasp that being hungry, for being under fed, working eighteen hours a day in a dimly lit noisy environment with guards looking for any excuse to beat you physically, always being tired for under sleeping in a bad environment, always being hungry and dealing with what was hinted as being such a complex wiring system that there were insufficient colours to distinguish all the required wires, would have just been an intolerable environment to work in, and produce a product free of defects. The core issue was common to both work environments, what mattered was getting the units out the door for production numbers. And it was just expected you'd get the wiring right first time. It was just too much to expect.
Why did I just spend 40 minutes watching a video about some archaic switch/button? .. I haven't got the faintest idea why.. But it was well narrated and oddly interesting
So good to see a new video! Hope you guys are doing well over there 🙂👍
Part of me knows that this information will be vital.... for me to be the guy who knows way to much about the a4/v2 /?R1? rocket. so thanks for enabling me to be "That Guy"
@Astronomy and Nature TV
Can you provide high definition wiring diagram?
Thank you very much for this awesome series, love the huge effort put into everything!
Very excellent explanation. Before 1937, Lockheed utilized a similar switch called the "wieght on wheels" switch to disable the electric landing gear actuator motor so the gear could not be retracted before the airplane was flying. The same concept is incorporated into modern retractable landing systems today. The same weight on wheels method is used to enable the spoilers and thrust reversers on many types.
There's a lot of similarities between A7Y and weight-on-wheels sensors, as it is simply a "weight-on-rocket" sensor.
I wonder whether or not it was tuned more to be accurate in the release, and in the microsecond range, while weight-on-wheels might be good within multiple microseconds, or a larger fraction of a second, and for loading as well as release. These seem to accomplish the same goal, but with very different constraints.
I know some German engineers designed their parts at the time with unnecessary accuracy, so it could very well be that these were also designed with measuring loading forces just as accurately as the releasing force. Would be interesting to know, as with the raw data for the response time.
Fascinating and superbly detailed as usual, thanks Robert.
But BILTEMA batteries, no wonder they lost the war 😂
Fantastic work! I'm binge watching your videos after rediscovering your channel. Great stuff!
40 minutes and I still don't know what the switch does.
Great video! Well done. Thanks Robert.
Electrical Engineer here. I can see that in the modern world a LOT of this design could be done today with a microcontroller and software. I appreciate the deep dive into this 1940s design with relays, motors, gears & cams driving contacts in sequence.
Just visited Peenemünde in parts because of this channel.
I would to have the V2 electric schematic diagram!. It's really interesting to see the German's designing choices at that time. Thanks for this really good research work!.
www.aggregat4.de/pdf/Ger%C3%A4tebeschreibung_A4.pdf
Your videos: Truly addictive. Thanks and congrats for superb information.
How did you acquire so much knowledge about the V2 systems? Are the technical schematics available to the public?
brilliant thanks
I can't get enough of these bloody rockets. Rocket motor to drive a turbo pump to pump the propellant into the rocket motor, neat eh?
Around 13 minutes....A simplified circuit diagram ..... this man produces extraordinary support materials like rabbits out of a hat! Another wonderful and strangely captivating episode of this magnificent series.
I did not seen video but put like, will watch later from bed for good night. Great work keep up the good work on these V2 rocket videos.
Ah, the perfect video to watch on a Friday night after the wife's gone to bed :)
A very interesting look at part of the takeoff circuitry of the V2 / A4 and the all important switch which triggers the systems to begin a chain of events because the rocket has left the pad and is on its way.
Thanks so much for sharing.
Fascinating stuff , I love the work that went into this video !!!
Thanks Robert !!!
Great to see you again! You're videos helped me through lockdown ⭐
"The" important switch. Well done Robert, A+ again.
Great video. I wonder what effect G forces had on the various relays during flight. I would imagine they were oriented on the missile to reduce the influence of these forces. The engineers must have put relays designed for telephone service through rigorous testing.
Really great series of videos. Many thanks!
Superb videos! Please do more videos about the guidance system and improvements over time.
Really impressing! The technical solutions founded by the engineers are really smart and elegant.
Their elegance was quickly burned away halfway falling through hell before meeting Lucifer 🔥👹🔱
You should use automatic washing machine's control unit (tiny electric geared program motor with drum of cams/contacts) for better illustration for your A4 electric model. Thanks a lot, it was really impressive! +1
Best video i've seen on this subject!!.A few years ago i built and flew several solid powered models of the v2.I know it sounds strange but pressing the launch button gave a strange excitement!!
Incredible tutorials from favourite “ fat “ Englishman. (I’m quoting him and I don’t think he’s fat)
There was a term in German "zwangsgeführte federunterstützte schaltmechanik" (force-guided spring-assisted switching mechanism) when you where looking for push buttons in electronics mail order companies. I guess this was meaning the same kind of switch-characteristcs though I can't find this term now anymore. I was using that kind of switch for my self-wound starting transformer. The same features microswitches have as well I suppose.
Missed out on the variable resistors Carbon film or swept wirewound.
The switch reminds me of pre-war ceramic light switches, lot of brass pivot points, fast , for early town DC supplies before Grid Enforcement.
Admiring the beautifully written piece of prose there at the end clearly defining the 'mission statement' for your presentations here. Their poignancy most correct...etc.
The irony then of Herr Von Braun's procurement by the American Authorities for 'peacetime scientific advancement'.
Nut's to what he and cronies did.
Powerful stuff.
Moving On. As we all had to...apparently.
Thank you for your illustrations. Simply fascinating insight.
That was brilliant. Hope to see more episodes in the future. Those engineers were so far ahead of their time.
Hi there, fantastic video, very informative. In what way do you think a V2 could have been sabotaged without detection during pre-launch tests? Thank you.
And to think that all that incredible Engineering and complex electronics would, after a short flight time be blown to smithereens as the Warhead contacts it's Target. I cannot help but wonder what these things cost to build? Of course the same holds true for modern equivalence of the V2. ICBM at the top end of the scale and possibly air to air missiles at the bottom end, they all cost millions to develop and more millions to build. All for man to wreak destruction on his fellow man, and along the way make huge profits for the armaments industry.
The way this electromechanical system works, with the central timer motor connected to various relays and switches, is exactly how an old pinball machine keeps score, adds bonuses and counts balls etc. Very clever.
Congratulations for this video about the technology of the A4-V2. In this and other videos, he presented schemes. Is there any way to make them available to those of us who are fascinated by rocket technology?
do I see the beginning of the PLC from Siemens?
Superb documentary
The switch actuation is called snap action, and is commonly used in instrumentation today.
All of this including the drum timer could be done with a simply designed PLC nowadays.
A well researched, well presented presentation of the A-72 launch switch. Thank you very much for the effort to make a complicated sequence of events so easy to follow.
Why wasn't the A4 or V2 accurate? It would often miss its target by up to 50km, yes?
19:45 V2 is the dark/evil ancestor of all automatic washing machines. ))))
With all of the knowledge you have shared with your videos, then viewing the old launch movie clips, one can understand and grasp what is taking place and when. Excellent production start to finish on all of your videos, thanks from Ohio in the USA.
Excellent 💚💚💚
🇮🇳💚🇺🇲
Looking for: “The Turbo Pump Part 2”! Where can I find it?
Hah! Who would have thought that my old washing machine had V2 technology in it!
Boy Von Braun was years ahead.
Id love to see a new video on the way they designed the bell of the rocket motor, and how they integrated cooling into the system that you mentioned in the video about the injector pots.
What a fascinating video--thanks so much for putting it together for us!
Hmm.. And I wonder why they called this rocket science.
These blueprints are amazing.
Blueprints always engage me, and the amount of copies, must make reproduction so expensive.
Modern wide base photocopying is so cheap (so many rehashes/mods :-)
Amazing video! Cant wait for more detalied videos (turbopump part 2 🤔😉) Did you make the model in Sweden? Those batteries are from Biltema and Kjell & Co. Swedish stores 🙂.
Biltema🙄 no wonder they lost the war 😂
Excellent presentation sir! Thank you!
Not sure why i need to know any of this but it's fascinating.
I thank you for this insight into the minds of the engineers that designed the V2.
When you say, "in detail", you really mean it!
Question Sir, Does your V2 display visit any of the Civilian Museums.... and does your Meade still work ?
Followed your diagrams and interconnection fine, but since so much sabotage was carried out, an external DC Sw(A72). would be very tempting. The pre-testing (missing) would be most important for the A7y relay (I Prefer ASEA relays, but not robust for lorries) and will not be heard, did the crew use a 'mulitester/dedicated' to discern free movement of both A72 and setting relay A7y.
Wiring - Rubber or asbestos insulation ? Love the 'tiny' trembler/bell vibrator 300hz Square A.C. Generator !
The Cam Switcher/programmer if not sealed, it would be delightful to spoil with, a quick contact depression of the thumb, would slow its rotation. Reviewing the Rkt schematic "they really passed over Timer Start Sw" .
As an enthusiast of understanding things of a retrotechnical nature, i found this to be thouroughly engaging. Thanks SO much for taking the time to show us!
Thank,s RobertI did some "Stuff 'as a young person in the USAF.Flt engineer Recip engineer training C-97,,C141A and Finally C-5a run qualified Tf-39 testing .What fascinates me is the seemingly reliance on german technoigy the USAF relies upon for jet engine development not to mention rocketry.For example the sequntial activation caused by A72.The 4 speed box and voltage regulator of the APU starting is almost identical.Having spent so many years of my youth in aviation your presentation has left me wondering about the panic situation that existed during the war to defeat Germany and Japan.It was a terrible cost in human lives.but if it wasn't stopped that next missle would have been tipped with nuclear war head,headed straight for Delancy street in Manhatten
Such an excellent series!
Quick trip to the hardware store and I’m building my own personal V2!!! Danke!!
Such detail that explains how technologic advanced the Nazis were in weapons development. Thank God for the allies being able to cut of their supplies in order to suspend further development. Scary to imagine how differently the outcome of the war could have turned. Great detail and visual explanation in all the videos I've watched. Instinctive and intuitive feeling whenever seeing an actual historical video of a launch of the V2 rocket. Will always have a different view when watching any documentary including the V2 in use against the allies. Thank You!!
Thank you so much for a look deep inside the functionality of this amazing rocket. After seeing one in person they have always fascinated me. The resemblance of latter liquid fuel rockets to the father of them all is obvious even after 20 years. Your vid is a gem, the best I've ever seen on this aspect of the control system. Amazing.
Absolutely amazing and how comprehensive these videos and descriptions are. I've learnt more and rehashed my basic knowledge more then most theirtube videos.
Thank you for the intuitive information.
Very interesting video, shows how small things were part of big things! Where can I get the technical drawings shown in the video? Thanks!!
There is a complete V2 at White Sands Missile Range's Missile Museum. Much of it is cut-away so you can see the inside construction. I was surprised that much of the circuits were mounted on a plywood stiffener up near the nose.
Love the model of the launch stand, your explanation started to sound like Eric Idles explanation of the attack plans in the sewer system in The Life of Brian.
So well documented and explained - every detail gets attention even the brandings of Siemens and Halske.
You might also know that in Dresden in the german military museum is another V2 rocket in the exhibition, but without that launch base I guess. Ihad been there last year before the video had been released otherwise I would have checked that V2 for the switch.
A72 in the A4 rocket as it had been called during developement if I remember right.
And it was a great idea to show the switch mounted on that rebuilded plate among the debris of that fin / rudder where it belonged. I watched it 3 times to get the full picture right.
Sorry! I would like I mean:)
Please sir thank you for the good work... I will like to chat you privately . Please what can I do
Great explanation. Thanks for taking the time, which must have been considerable, to make the model to help our understanding. Excellent video.
I guess there's no chance of getting to watch the video of the umbilical cable system with *useful* audio.
This is the sort of electrical stuff I live for. I have worked on some technical plants over the years and I love it
Clever machine, dark and deadly. Now I understand more! Thanks!
Great, superb video! and very well explained, as ever. Thanks Robert!
Love the deep dive videos
Thanks for another great vid Robert (But what about the 8 ton valve!!! lol)
This series is so good I look forward to each one. This is my third time watching this video
Very well explained and presented !! Thanks so !
Hi and thanks. Don't forget to subscribe if you want to see more like this - and be sure to take a look at Turbopump Part 2, which looks at some surprising physical effects of the pump system on the rocket in flight. ruclips.net/video/CmTxAFY03fU/видео.html Best wishes A&NTV
Thanks very interesting
_Staatsgehiemnis !_
Take a shot every time rob says "fin number one"
Thank your amazing deep-dive video! My question is was the control feedback loop using PID or just P (proportional) control? From what I gathered from videos, the control fins and vanes were counteracting the error signal from gyros only in proportion? If so, certainly a deliberate design choice to simplify the missile control unit.
Helmut Hoelzer’s Fully Electronic Analog Computer used in the German
V2 (A4) rockets
Synopsis: A fully electronic general-purpose analog computer was designed by Helmut
Hoelzer, a German electrical engineer and remote-controlled guidance specialist. He and an
assistant built the device in 1941 in Peenemunde, Germany, where they were working as part
of Werner von Braun’s long-range rocket development team. The computer was based on an
electronic integrator and differentiator conceived by Hoelzer in 1935 and first applied to the
guidance system of the A-4 rocket.
www.cdvandt.org/Hoelzer%20V4.pdf
Another fantastic video! Loved the animation at the end!
I love circuitry
Great really great
Elvis switch...
Very interesting
''click'' mouhahaha
Thank you very much for sharing !
🇮🇳💚🇬🇧
Fantastic display as always! Thank you!
How did they aligned the rocket to point to the target? I know the Lance rocket had a whole team of land surveyors to properly mark the launch location and calculate the direction to which the rocket should be launched.
The rocket was on a rotating turntable. They knew the compass heading from the launch location to the target and just rotated the rocket so that fin number 1 was pointing toward the target. I'm not sure how they set the range of the rocket though. I'm guessing it was done by setting the rocket to fire for a specific length of time, using the timer system that was started by switch A72 at launch.
@@williamgreen5575 I believe it was the opposite - the velocity was measured (integrating the acceleration through time) and when the preset velocity was reached (which depended on desired range), the engine was cut off.
really great video.
This build up was amazing
Hmm. I can relate to the wiring issues more directly than I realise. My first job after leaving school, 1981, was wiring mobile telephone handsets to the transmitter/ receivers and logic boards using a 20 way un-colour coded ribbon cable. This meant all 20 wires, bar one, were coloured grey an looked the same, while having to be hand soldered to their respective contacts in different locations across the unit. This produced a rats nest of grey wires going everywhere. One wire had a red stripe trace, and that was wire No.1. And virtually every handset made had an initial wiring fault because with all the wires so closely bunched, it was just too easy to pick up the wrong wire in the sequence, or mis-count from a re-check to double check the wire count/ termination. Usually any double check, and a double check the double check lead to a different count leading to doubt on the work just done. The best way to check the wiring was to plug it in, but due to costs of components at the time, this was not possible until the unit was installed where it was meant to be, reliably considered, a new and fully functioning unit. It rarely ever was that until the installation engineer plugged it in and now identified by subsystem fault where the likely wiring issue was. But this all added time and frustrated them.
Now I can grasp that being hungry, for being under fed, working eighteen hours a day in a dimly lit noisy environment with guards looking for any excuse to beat you physically, always being tired for under sleeping in a bad environment, always being hungry and dealing with what was hinted as being such a complex wiring system that there were insufficient colours to distinguish all the required wires, would have just been an intolerable environment to work in, and produce a product free of defects.
The core issue was common to both work environments, what mattered was getting the units out the door for production numbers. And it was just expected you'd get the wiring right first time. It was just too much to expect.
Just add water.
Thank you
Best system
Awesome
Amazing breakdown right down to a little Button into a Switch , unleashing Destruction...Great Vid.