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>A code to unlock the missile had to be dialed into six thumbwheels of 16 numbers each Could it be they were using a hexadecimal based system?

by dsq 10y ago

Jgrubb 10y ago
Thought the same thing, it would have to be no?
- dsq 10y ago
  You're right, apparently not hexadecimal. I found a photo of the code thumbwheels: http://static1.businessinsider.com/image/55b7d71a371d2279018ba74e-538/screen-shot-2015-07-28-at-15549-pm.png http://static1.businessinsider.com/image/55b7d71a371d2279018...
  - CamperBob2 10y ago
    Those were probably so-called "BCD" switches. You had four data lines because that's what it takes to represent all digits from 0-9, but not all 16 combinations could be dialed up, just 10. The result of putting N switches together in a control panel is a BCD number where N decimal digits are represented with N*4 binary lines. There are a lot of surplus BCD and other types of thumbwheel switches on eBay, but I'm not sure if they're still being made these days.
joosters 10y ago
Was this the code that was actually set to 0000000 ? I can't find the reference, but I'm sure I read somewhere that the launch codes were not properly set up for a long time...
- arethuza 10y ago
  That was Minuteman missiles and it was 00000000 - so over 10 (or 16) times as secure! https://en.wikipedia.org/wiki/Permissive_Action_Link#Development_and_dissemination https://en.wikipedia.org/wiki/Permissive_Action_Link#Develop...
- mrec 10y ago
  It wasn't a "not properly set up" thing, it was the military deliberately pushing back against safeguards they saw as making the US deterrent less credible.
  - effie 10y ago
    That would work if they made the password full of zeroes public. But did they? I think it's more likely they wanted to increase probability of correct execution. So they prepared for the possibility the correct passwords to launch would not be available when needed, in the simplest way - have a password that is easily remembered.

>A code to unlock the missile had to be dialed into six thumbwheels of 16 numbers each Could it be they were using a hexadecimal based system?

by dsq 10y ago

>A code to unlock the missile had to be dialed into six thumbwheels of 16 numbers each Could it be they were using a hexadecimal based system?

Jgrubb 10y ago

Thought the same thing, it would have to be no?

dsq 10y ago
You're right, apparently not hexadecimal. I found a photo of the code thumbwheels: http://static1.businessinsider.com/image/55b7d71a371d2279018ba74e-538/screen-shot-2015-07-28-at-15549-pm.png http://static1.businessinsider.com/image/55b7d71a371d2279018...
- CamperBob2 10y ago
  Those were probably so-called "BCD" switches. You had four data lines because that's what it takes to represent all digits from 0-9, but not all 16 combinations could be dialed up, just 10. The result of putting N switches together in a control panel is a BCD number where N decimal digits are represented with N*4 binary lines. There are a lot of surplus BCD and other types of thumbwheel switches on eBay, but I'm not sure if they're still being made these days.

joosters 10y ago

Was this the code that was actually set to 0000000 ? I can't find the reference, but I'm sure I read somewhere that the launch codes were not properly set up for a long time...

arethuza 10y ago
That was Minuteman missiles and it was 00000000 - so over 10 (or 16) times as secure! https://en.wikipedia.org/wiki/Permissive_Action_Link#Development_and_dissemination https://en.wikipedia.org/wiki/Permissive_Action_Link#Develop...
mrec 10y ago
It wasn't a "not properly set up" thing, it was the military deliberately pushing back against safeguards they saw as making the US deterrent less credible.
- effie 10y ago
  That would work if they made the password full of zeroes public. But did they? I think it's more likely they wanted to increase probability of correct execution. So they prepared for the possibility the correct passwords to launch would not be available when needed, in the simplest way - have a password that is easily remembered.