Help Support Fran's YouTube Channel on Patreon: http://www.patreon.com/frantone
UPDATE Feb. 4, 2013: for final analysis and descriptions of the LVDC logic devices read my blog posting here: http://www.frantone.com/designwritings/design_writings.html #LVDCcode
My preliminary analysis of the Saturn LVDC board:
- The X-ray image is negative, so white elements are completely blocking the X-rays while black parts show no obstruction. Most of the board is grey due to the continuous ground plane and overlapping traces, and white spots mostly indicate lead solder.
- Each logic device package contains 4 semiconductors. The ceramic wafer bases of each logic package have conductive traces deposited on both the top and bottom sides, and the semiconductors (called Flat Chips) are surface mounted with solder balls by reflowing to these traces face down on the top side of the wafer (it has been noted that the later IBM 360 logic devices were made in this manner- see link below). The small white square shapes you see arranged in threes are the solder pads connecting each semiconductor to the traces.
- The board has a continuous ground plane layer, and the only openings are around the vias, which you can see as a black ring around all of the via pads that show a clearing through all layers.
- The logic packages do not appear to contain capacitors.
- This board has a lot of layers!
- The bone in my thumb is apparently not broken. 🙂
Full size images and updates available on my engineering page here: http://www.frantone.com/designwritings/design_writings.html #xray
More documentation online about the LVDC:
http://www.spaceaholic.com/lunar_module_saturn_v.htm
http://ibiblio.org/apollo/Documents/LaboratoryMaintenanceInstructionsForLVDC-Volume1-GeneralDescriptionAndTheory.pdf
http://ibiblio.org/apollo/Documents/LaboratoryMaintenanceInstructionsForLVDC-Volume2-MaintenanceData.pdf
The IBM 360 devices: http://www.cs.auckland.ac.nz/historydisplays/FourthFloor/MainFrameComputers/IBMSystem360.php
UPDATE Feb. 4, 2013: for final analysis and descriptions of the LVDC logic devices read my blog posting here: http://www.frantone.com/designwritings/design_writings.html #LVDCcode
My preliminary analysis of the Saturn LVDC board:
- The X-ray image is negative, so white elements are completely blocking the X-rays while black parts show no obstruction. Most of the board is grey due to the continuous ground plane and overlapping traces, and white spots mostly indicate lead solder.
- Each logic device package contains 4 semiconductors. The ceramic wafer bases of each logic package have conductive traces deposited on both the top and bottom sides, and the semiconductors (called Flat Chips) are surface mounted with solder balls by reflowing to these traces face down on the top side of the wafer (it has been noted that the later IBM 360 logic devices were made in this manner- see link below). The small white square shapes you see arranged in threes are the solder pads connecting each semiconductor to the traces.
- The board has a continuous ground plane layer, and the only openings are around the vias, which you can see as a black ring around all of the via pads that show a clearing through all layers.
- The logic packages do not appear to contain capacitors.
- This board has a lot of layers!
- The bone in my thumb is apparently not broken. 🙂
Full size images and updates available on my engineering page here: http://www.frantone.com/designwritings/design_writings.html #xray
More documentation online about the LVDC:
http://www.spaceaholic.com/lunar_module_saturn_v.htm
http://ibiblio.org/apollo/Documents/LaboratoryMaintenanceInstructionsForLVDC-Volume1-GeneralDescriptionAndTheory.pdf
http://ibiblio.org/apollo/Documents/LaboratoryMaintenanceInstructionsForLVDC-Volume2-MaintenanceData.pdf
The IBM 360 devices: http://www.cs.auckland.ac.nz/historydisplays/FourthFloor/MainFrameComputers/IBMSystem360.php
My dentist would charge me $300 to do that…
wish youd had edited out the high pitch ringing! then again its only two brief intervals and maybe its just my ears being young enough
When ISN'T Fran doing something cool…!!!???
A medical device has enough power?
I would have thought that one sees nothing. Luckily they did not use fully metalized layers.
You should have made stereoscopic pairs. ^^
A stereographic pair would be nice.
That is awesome Fran. ✔
You are lucky to know people that'll give you access to their high tech equipment. 🔬
Beware of exposure to X-ray too much…
This was the kind of content that brought me and many others to Fran's channel here on YouTube.. but she's decided to go other directions… 🙁
Amazed again, and still dreaming. Love this!! ☺
I imagine you may have come across this by now, but I was familar with IBM SLT before hearing about the LVDC mainly from the "IBM's 360 and Early 370 System", the book says there was a film resistor trimming machine which measured the resistance and trimmed material away by sandblasting.
Fran, I wish I would have married you because you probably could have fixed my HP41CV and I could still be using it. Oh well, what could have been.
Back in 1982 I worked at a computer company named TANO in New Orleans East. They made computerized ship board controls, bldg. control systems and pipeline control equipment. Lots of circuit boards, sensors, remote terminal units, intelligent terminal units, etc. One of the things I noticed there was a draftsman (woman) drawing very large layouts, maybe 6' x 4' on a vertical board and she sat on a tall chair. The dwgs were ink on clear film. I pretty sure they were circuit boards that had been designed in house. Someone explained how the photolithography process worked and that was something that was done in house also. I always thought that the layout would make a nice wall hanging.
TANO used DEC PDP 11 computers and I think they had 2 VAX's. I bought my C-64 that year and Tron came out also. 1982 was a good year.
Incredible!
OMG How beautiful !
@fran since you only have half a board, I suggest to remove an 'AA B' and an 'INV 1', plug them into a scanner and deduce their internal logic. That is all you can do. I think the special sauce was in the missing ICs.
You should check out gideonlabs[DOT]com . Three words to describe that site is "component failure analysis". It's definitely worth a look since they have a lot of pictures of uncapped ic's. The one thing that came to mind about the finger x-ray was the "X-ray Shoe Fitter"(search in google images). That takes me back to the days when the history channel was actually educational. Those where the days 🙂
Nice of them to let you do that
Interesting. To a modern eye the SMT packages tend to make you think theres more inside than what looks like 12 discrete transistors. I'd question 12 layers though. The period hand layup dates it nicely though. 🙂