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on this page:
(November 2013 - December 2013)
Apollo Saturn V LVDC Board Teardown, Part 3
Apollo Saturn V LVDC Board Teardown, Part 2
Fran's Space Attack! Make Your Own Video Multicade
The Apollo Hoax Conspiracy Epidemic
Ghost In The Machine
Music Gear Builders Group Meeting
- LVDC Project Update -
(December 26, 2013)
Dave Jones at EEVBlog receives the LVDC page assembly board!
Now I will pass the board along to another engineer in our community, and they will add their skills to deconstructing this relic, and perhaps revealing more of its secrets. To be continued!
Chip type #321 was the first
to come off the LVDC board, and I found that the coating on the underside
which was covering the resistive elements was in fact a thin rubbery coating
of some kind of silicone. I successfully removed the coating by gently
using a small screwdriver to distress the silicone, then brushed it off
of the ceramic wafer with a medium bristle toothbrush. Using my DMM
I found the values to be very precise, and the mechanically trimmed deposited
film resistors are indeed very accurate in value.
My first attempt to open
one of these device packages was not elegant - I broke the thin ceramic
top off of #321 in pieces, which revealed a pink putty-like silicone fill.
Removing the potting I found
that the package was empty - no traces, no semiconductors. It seems
that #321 is simply two resistors, nothing more.
This is the cleaned interior
of a type #322 package -
I used a sharp chisel to
open each package by prying off the cover.
Inside each device package
was a pink silicone based putty that filled the cavity.
I carefully picked away the
filling to reveal the circuitry inside, but as it turned out my light touch
was not light enough. I accidentally dislodged many of the semiconductors
from their mounts in the process.
Missing transistors.... Doh!
I found them in the potting I pulled out later. Those traces are
wide, but the mounting points on the semiconductors are microscopically
small, just a few mils across at best. Not much surface area for
the solder joints.
Resistors on the underside
of the AB type device package - I damaged the one on the far right while
taking the silicone coating off. This is much harder than it seemed
to remove the potting without damaging the electronics.
are very small - here a normal pencil point is placed in view for scale.
Close up of a transistor
I inadvertently snapped off:
When chipping off the top
cap of one of the device packages I dislodged a wafer slightly, and accidentally
discovered that the leads on these logic device packages were actually
held by spring tension to deposited metallic contacts on the bottom and
top sides of the ceramic base wafer. The leads are not soldered to
the devices, but instead each making purely mechanical contact to the base
wafer. A conductive medium might be present in the clip part, but
that should get further investigation by another engineer in the project.
Another great reason why these page assembly boards were so very heavily
conformal coated for flight - not just because of the liquid cooling throughout
the LVDC, but it would also have been necessary to prevent the devices
moving out of place due to the extreme vibration of the Saturn V in flight.
So many people have asked about my Space Attack! cabinet and how to make a multicade so here is a simple overview of what you need to do. A project like this has lots of details that you mostly have to work out yourself because of the differences in cabinets, monitors, game PCB pinouts, and controller options - but this video shows how to get started and the basics you will need to work out. I built this cabinet in 2000 to run original arcade PCB game board pulls, but converted to multicade PCB in 2007.
Fran Plays Phoenix!
Here I play a quick game of Phoenix on my custom built vertical Multicade. Even though I have played this game since around 1980 I still utterly stink at it. But it is still fun!
I am tired of the endless outpouring of videos from Apollo hoax nuts - time to rant!
Lunar Reconnaissance Orbiter photos of the Apollo Landing Sites - http://www.nasa.gov/mission_pages/apollo/revisited/#.UnayKlPSi9I
YouTube is part of the problem - Here is a screenshot of the contrary keyword suggestions I mention for video uploads.
Hank expires unexpectedly on camera. The Horror.... The Horror.
A sneak peek at my new workspace - FranLab!
I joined a group of fellow builders to talk space, show off some cool gear, examine a genuine Saturn V engine component first hand, shoot the breeze, and even jam out a bit. All good fun - and here are some assorted highlights. Enjoy!
Potofone Ribbon Mics - http://www.potofone.com/index.html
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