A story appeared on Slashdot about a mysterious fax received at Fermilab written in an unknown code. The full story is here. I looked at it and immediately noticed a few things:

1. The first part looked like ternary (base 3) with digits 1 (|), 2(||) and 3(|||).

2. The last part looked like binary with digits 1(|) and 2(||)

3. The middle bit looked like either a weird substitution code, or I wondered if it might be machine code.

4. In the last part the digit 2 (||) never occurs more than once, perhaps it was actually a separator and the last part is not binary.

The first step was to convert the bars into numbers. Here's a copy of my marked up print out:

The first part has the numbers (or at least I thought):

Noticing this had 113 digits (which is a prime number) I went off on a wild goose chase around primes, and then around the interpretation of this number in hexadecimal as a string in ASCII, Unicode or binary... waste of time.

Then I started thinking about ternary again and wrote down the largest ternary numbers that can be expressed with 1, 2, 3, ... digits:

One of those stood out: with three digits the maximum number is 26 and there are 26 letters in the alphabet! Then the only question was was how to map the three digits used in the code (1, 2, 3) to the three ternary digits (0, 1, 2).

To simplify things I wrote a small Perl program that tries out all the possible mappings and outputs the ternary interpreted as a string (with 001 = A, etc.):

With my initial interpretation of the top part of the coded message I got the following output:

A ha! The 021 block (which corresponds to the mapping 3 -> 0, 2 -> 2, 1 -> 1) seems to have a partial message: [email protected]@WOULD and then it's garbage. Going back to the original message I realized that 113 is not divisible by three and that I'd either missed a symbol, or had two too many.

After much fiddling around I discovered that the correct interpretation of the top block is that two of the threes are wrapped from one line to another (there appears to me some indentation in the message that indicates this, take a look at the original, but this could be just random).

Rerunning my Perl program output the full message:

So much for the first part. The second part took me off into Z-80, 6502 and 6809 machine code wondering if it was a program and then nowhere. I still don't understand what this part is trying to say.

The third part looked initially like binary but on closer examination I decided that the 2s (||) were actually separators and the message should be interpreted as number separated by 2s by counting the 1s (|). That yields:

(Once again there was a wrapping 'problem' in the message where a run of 8 |s was actually 3 |s then 1 || and 3 more |s.) Using the little Perl program reveals:

So, the same mapping between digits is used.

That leaves some final questions:

1. Who is Frank Shoemaker?

2. Why is base spelt incorrectly?

3. Is the extra S in BASSE a reference to the middle section where three symbols start with S.

4. If #3 is correct, then those three symbols could be intepreted as FC

5. Why is the letter A missing from the middle section when all the other hexadecimal digits are there?

1. The first part looked like ternary (base 3) with digits 1 (|), 2(||) and 3(|||).

2. The last part looked like binary with digits 1(|) and 2(||)

3. The middle bit looked like either a weird substitution code, or I wondered if it might be machine code.

4. In the last part the digit 2 (||) never occurs more than once, perhaps it was actually a separator and the last part is not binary.

The first step was to convert the bars into numbers. Here's a copy of my marked up print out:

The first part has the numbers (or at least I thought):

323233331112132

333231322123312

111331132312233

333212123213113

311333313331111

211333323232211

232313331121231

33231312

323233331112132

333231322123312

111331132312233

333212123213113

311333313331111

211333323232211

232313331121231

33231312

Noticing this had 113 digits (which is a prime number) I went off on a wild goose chase around primes, and then around the interpretation of this number in hexadecimal as a string in ASCII, Unicode or binary... waste of time.

Then I started thinking about ternary again and wrote down the largest ternary numbers that can be expressed with 1, 2, 3, ... digits:

2

22

222

2222

2

_{3}= 2_{10}22

_{3}= 8_{10}222

_{3}= 26_{10}2222

_{3}= 80_{10}One of those stood out: with three digits the maximum number is 26 and there are 26 letters in the alphabet! Then the only question was was how to map the three digits used in the code (1, 2, 3) to the three ternary digits (0, 1, 2).

To simplify things I wrote a small Perl program that tries out all the possible mappings and outputs the ternary interpreted as a string (with 001 = A, etc.):

use strict;

use warnings;

my $top = $ARGV[0];

$top =~ tr/321/abc/;

my @chunks;

while ( $top =~ s/^([abc]{3})// ) {

push @chunks, $1;

}

my @digits = ( '0', '1', '2' );

foreach my $d0 (@digits) {

foreach my $d1 (grep {!/$d0/} @digits) {

foreach my $d2 (grep {!/[$d0$d1]/} @digits) {

print "($d0$d1$d2) ";

foreach my $c (@chunks) {

my $v = 0;

my $m = 1;

foreach my $d (reverse split( //, $c )) {

$d =~ s/a/$d0/;

$d =~ s/b/$d1/;

$d =~ s/c/$d2/;

$v += $d * $m;

$m *= 3;

}

print chr( 64 + $v );

}

print "\n";

}

}

}

With my initial interpretation of the top part of the coded message I got the following output:

(012) [email protected]@[email protected]@CJQJFBWKAF

(102) JDNXUMEISOZNUODMFSGYQMPNZHMJCHCPNTELP

(120) [email protected]@RMPWRWJLFUNJ

(201) THYLOZGRKUMYOUHZCKENVZWYMDZTFDFWYJGXW

(210) [email protected]@IZWPIPTXCOYT

(012) [email protected]@[email protected]@CJQJFBWKAF

**(021) [email protected]@[email protected]@FTVTCAPSBC**(102) JDNXUMEISOZNUODMFSGYQMPNZHMJCHCPNTELP

(120) [email protected]@RMPWRWJLFUNJ

(201) THYLOZGRKUMYOUHZCKENVZWYMDZTFDFWYJGXW

(210) [email protected]@IZWPIPTXCOYT

A ha! The 021 block (which corresponds to the mapping 3 -> 0, 2 -> 2, 1 -> 1) seems to have a partial message: [email protected]@WOULD and then it's garbage. Going back to the original message I realized that 113 is not divisible by three and that I'd either missed a symbol, or had two too many.

After much fiddling around I discovered that the correct interpretation of the top block is that two of the threes are wrapped from one line to another (there appears to me some indentation in the message that indicates this, take a look at the original, but this could be just random).

323 233 331 112 132

333 231 322 123 312

111 331 132 312 233

333 212 123 213 113

311 333 313 331 113

113 333 232 322 133

231 333 112 123 133

231 312

323 233 331 112 132

333 231 322 123 312

111 331 132 312 233

333 212 123 213 113

311 333 313 331 113

113 333 232 322 133

231 333 112 123 133

231 312

Rerunning my Perl program output the full message:

(012) [email protected]@[email protected]@[email protected]

(102) JDNXUMEISOZNUODMFSGYQMPNYYMCIVEMXSVEO

(120) [email protected]

(201) THYLOZGRKUMYOUHZCKENVZWYNNZFRQGZLKQGU

(210) [email protected]

(012) [email protected]@[email protected]@[email protected]

**(021) [email protected]@[email protected]@[email protected]**(102) JDNXUMEISOZNUODMFSGYQMPNYYMCIVEMXSVEO

(120) [email protected]

(201) THYLOZGRKUMYOUHZCKENVZWYNNZFRQGZLKQGU

(210) [email protected]

So much for the first part. The second part took me off into Z-80, 6502 and 6809 machine code wondering if it was a program and then nowhere. I still don't understand what this part is trying to say.

The third part looked initially like binary but on closer examination I decided that the 2s (||) were actually separators and the message should be interpreted as number separated by 2s by counting the 1s (|). That yields:

31211112111312

32213123123331

12213111332312

23333333233123

12313123332311

33223232312312

112

31211112111312

32213123123331

12213111332312

23333333233123

12313123332311

33223232312312

112

(Once again there was a wrapping 'problem' in the message where a run of 8 |s was actually 3 |s then 1 || and 3 more |s.) Using the little Perl program reveals:

(012) [email protected]@[email protected]

(102) OZTYSBOOMXGZLODMLNEEOMEVACOOX

(120) [email protected]@NKVMNLUUKMUDYWKKB

(201) UMJNKAUUZLEMXUHZXYGGUZGQBFUUL

(210) [email protected]@YSQZYXOOSZOHNPSSA

(012) [email protected]@[email protected]

**(021) [email protected]@[email protected]**(102) OZTYSBOOMXGZLODMLNEEOMEVACOOX

(120) [email protected]@NKVMNLUUKMUDYWKKB

(201) UMJNKAUUZLEMXUHZXYGGUZGQBFUUL

(210) [email protected]@YSQZYXOOSZOHNPSSA

So, the same mapping between digits is used.

That leaves some final questions:

1. Who is Frank Shoemaker?

2. Why is base spelt incorrectly?

3. Is the extra S in BASSE a reference to the middle section where three symbols start with S.

4. If #3 is correct, then those three symbols could be intepreted as FC

_{16}which is 252. Could this be the employee number of the author?5. Why is the letter A missing from the middle section when all the other hexadecimal digits are there?

## Comments

It would appear that Frank Shoemaker is a physicist who worked on the BooNE neutrino experiment.

Gives an email address for a FRANK C SHOEMAKER.

Random thought: the S could be the missing symbol for A, so the SDt => AFC_16 => 2812.

Interestingly, there is a Fermilab person with ID 252 (0xFC) called Pierre PirouÃ© (he's a professor at Princeton).

I sent him a mail.

http://www.fermilabtoday.com/pub/about/whatis/wilsonhall.html

note the references to "basse"

Marduc/Craig... the basse speculation is interesting. Perhaps this person simply worked in that building.

http://technet.microsoft.com/en-us/library/ms947792.aspx

Googling "phi value encryption" gave something on RSA Alogrithm in the results that might be interesting. Dunno if there's other methods that use the phi value, but that's the first one that popped up.

Also note that the first two lines match up in spacing and pattern. So the legible text and line above it are possibly a key to the remaining encrypted text. I'd suspect that if you figure the offset of the readable line and the line above and use some encryption formula (just might be RSA) to further shift that, it might say something legible.

What I'm wondering is if there's something more interesting to it, or just some exchange between bored physicists with ciphers/cryptography as a side hobby. Another guess is that it's some thought out promotional stunt for using RSA encryption.

any Germans working at Fermilab?

Or perhaps it is coming from someone from a German research institute that worked with Frank Shoemaker?

This link has lists research centers:

http://www.rarf.riken.go.jp/rarf/np/nplab.html

for some reason, GSI drew my attention...

doing a search on 'element' brought me to the link for element 111:

http://www.gsi.de/forschung/kp/kp2/ship/el111_e.html

you were talking about '2812'. Notice the pages that are mentioned in the link 281-282... probably a coincidence

Why 46? Might be just the number of cells per line on a sheet of ruled paper. My A4 pad with a 0.5cm grid inside significant margins has 47 cells to the long side.

Pierre Piroue was on the faculty then, so these guys know each other.

Shoemaker must be quite elderly now, in his eighties (I'm 56, and he had to have been at least 40 when I took his course in 1970.)

My guess is that the coder has a Princeton connection, but who knows?

David Derbes

U of Chicago Lab Schools

[email protected]

Subtract FC?

Swap F and C?

35549 or 35569

Cipher: [email protected]@[email protected]@[email protected]

Key:????(Don't know yet)?????

Message: [email protected]@[email protected]@[email protected]

Now on the next four lines, notice how the placeholder @'s on the top two also line up with the @'s on the bottom two.

So let's try making the top two lines the code, and the bottom two lines the key. (or vice versa)

Code: JDNXUMEISOZNUODMFSGYQMPNYYMCIVEMXSVEO

Key: THYLOZGRKUMYOUHZCKENVZWYNNZFRQGZLKQGU

Message:

?????

I'm not sure if a simple alpha grid is the right way... (ABC across, then from A, ABC down. Fill out the grid and rollover.) That seems like it'd be too easy to solve, but it looks like it might say something. So go down vertically on the left to J, then across to where T is. Now go back vertically to the top from where T is, and you get K. Etc, etc. Looks like it spells out some actual words, or perhaps a person's name. (At least from the first dozen letters or so I looked at. I don't have a straight edge and a printout to make following the grid easier at the moment.) But if it's that simple, then what's the middle part about?

On another tangent, somebody at SlashDot was saying "basse 16" could be actually referring to a building in a pecular way. (Something about the Wilson Hall design relating to some cathedral in France. Crazy stuff (almost like DaVinci code or something), but interesting none the less.) What if "employee number" wasn't an ID thing, but rather how many people were working there at the time the code was made?

Converting Hex to ascii takes a pair of hex numbers, and without the S there are exactly 13 pairs of numbers or 13 letters. So translating:

F0 BE 58 F2 FD 63

6C 79 D2 E3 93 E6

FC

gives us:

Ã°¾XÃ²Ã½c

lyÃ’Ã£“Ã¦

Ã¼

This is just a load of gibberish, so maybe there's a trick to it. The only hint I can think of is the extra S, which you can convert into the hex number 53. Maybe applying it in some way to the hex numbers will decipher it, but I'm too tired to think about it more.

16° 0′ N, 61° 43′ E !

Something else to look at :)

Notice that in your final Perl decode of section 1, reading *down*, column-wise, the same string of "@@MMZZ" occurs after each(?) word break.

Have at it!

http://www.fnal.gov/pub/about/campus/wilsonhall.html

Basse Ouevre has 7 columns on the back of it. in the 1st and 3rd stanza there are 7 sets and and an 8th partial. the Basse Ouevre's columns are in a semicircle, the center one could count as a 2 if you viewed the building from one side the other allowing the center column to double itself visually.

Anyone know how to do an analysis to figure out the date when the northern sky looked like that?

"FRANK SHOEMAKER WOULD CALL THIS NOISE" might be interpreted as "Frank S. would make a phone call to the number embedded in this (what seems to be) noise". Once connected, you'd have to ask for employee #252 -- or dial the extension.

The difficult part is finding a phone number in there...

Here are some ideas, but I haven't come up with any solution yet.

Replacing the 24 symbols with their respective frequency yields

311 311 323 232

311 222 312 233

or, with the usual modulo-3 mapping

011 011 020 202

011 222 012 200

that makes decimal

4 4 6 20

4 26 5 18

-- which doesn't look anything like a phone number.

Maybe each column gives one digit:

044255072806 or 044677056802

-- still not good

Maybe interpreting the numbers as letter as before and then dial that string using the letters on phone buttons?

DDFTDZER -> 33383937

-- still no luck.

(at least not if we assume that it is a US number)

All that assumes that the hexadecimal mappings are there only to decypher the employee number 0xfc -- and to give a hint to look at the frequencies, as it would otherwise have redundant entries.

Still, phone number or not, I think we are missing something obvious. The top and bottom part have been rather straight forward, almost simple. I don't expect the middle part to have some super-complex multi-layered encryption.

What if BASSE SIXTEEN is a phone number? It works as a 10 digit phone number with a 2 digit extension... if you map the letters to the keypad of a phone.

Just a thought.

BTW: comes out to (227) 737 4983 #36 a Maryland Number... Lots of employees from University of Maryland there...

F0 BE 58 F2 FD 63

6C 79 D2 E3 93 E6

???

If we assume that it is a sequence of bytes and then decode it using the tertiary code of the other two parts, we will get ...

012 212 000 010 210 102 010 120 200 201 010 211

011 121 202 210 202 022 110 201 002 220 012 220

[email protected]

:(

http://www.research.att.com/~njas/sequences/Seis.html

this link shows at least the second and third sets of numbers related to eachother

http://www.research.att.com/~njas/sequences/b006218.txt

If you're having trouble spotting it, polaris is to the right of the last line on the first paragraph.

Also, it might have some kind of filter, or perhaps not be optical, as stellarium doesn't have the small triangle of stars above the 4th character of the 2nd paragraph.

(oh, there seems to be virtually zero chance to match this to a time/date when it was taken as there seem to be many many dates when it appears to match up... either that or there's some trick to date-by-stars I'm unaware of...)

...what's bugging me is what do the stars have to do with frank shoemaker, or is it perhaps just coincidence that it was the nearest piece of scrap paper to the author at the time?

When I did it I got:

120000102112012022120002120111020010020110021100111002112011100010112020

>6C 79 D2 E3 93 E6

I think that should be read as:

F6 0C B7 E9 5D 82 FE 23 F9 D3 6E 36

or:

6F C0 7B 9E D5 28 EF 32 9F 3D E6 63

I just think loundly:

what if we consider that to be simpler than what it seems.

I think "basse sixteen" means the hex 16 in little endian.

starting from this we can have :

'employee number 620' (to octal)

'employee number 1021' (in hex)

please try to find if these ID refer to the author

My second thought is that the middle part is some machine code, and all the symbols are in fact just what Mr Shoemaker calls "noise", we just need to know that phi referes to 7 and S to FC

F7 BE 58 F2 FD 63

6C 79 D2 E4 93 E6

FC

it looks like some machine code that we can translate to assembly(I did some assembly last year and it seems to be similar to some code I saw)I'll try to translate it tomorrow.

"employee number E6FC" ?

or S.F.C stands for the

Signature ofShoemakerFranck ?Here is what I found:

0=U+0069 (lower case i)

2=U+203A (single right pointing angle quotation mark)

3=U+29A3 (reverse angle)

4=?

5=? (looks like a circle, but with a mark on the lower right)

6=U+00AC (not sign)

7=U+03A6 (Greek capital phi)

8=U+2E07 (Raised dotted interpolation marker)

9=?

B=U+002D (minus sign)

C=possibly U+03BB (lower case lambda)

D=U+10E2 (Georgian letter Tar)

E=U+27D3 (Lower right corner with dot)

F=U+25C4 (white left pointing triangle)

It is odd to have the hex with the symbol. If you are going to hide a message in hex, doesn't that make the symbols redundant? The person that made this isn't that silly. Maybe the message is hidden in the unicode bits all combined, and the hex digit is actually some kind of checksum? Within Unicode, there are many similar symbols with different code. A checksum of some sort would be a way to ensure the reader has the right unicode for the symbol.

> Anyone know how to do an analysis

> to figure out the date when the

> northern sky looked like that?

It could be the southern sky just to confuse people.

I'm thinking it's possibly referring to an astronomical event that was captured on the film in question...

16° 0′ N, 61° 43′ E

as the point of view. this is the exact possition of the city basse-terre on the caribian island guadeloupe.

i believe that it is more than an incident that this city is exactly at 16° 0' N. isn't it quite unlikely that the text reffers to basse 16 and this place doesn't have any thing to do with it?

but the full name of this schoemaker was Eugene Merle Shoemaker

shows up the 'missing' stars when compared to stellarium.

To the people who think it's fax noise, yes, faxes are noisy, but the correlation of the larger of these noise dots to star positions is way too strong to ignore! I wish I had a scanner here to show you the map and how it compares... Plus, there's the link to 'noise' that is referred to in the first paragraph, which given the almost perfect correlation I'm reasonably confident that's what they're on about.

The question to me is, is there more information to be had out of this star chart, or is the clue about noise just so we don't ignore the background image...

The first block:

(012) [email protected]@[email protected]@[email protected]

(021) [email protected]@[email protected]@[email protected]

(102) JDNXUMEISOZNUODMFSGYQMPNYYMCIVEMXSVEO

(120) [email protected]

(201) THYLOZGRKUMYOUHZCKENVZWYNNZFRQGZLKQGU

(210) [email protected]

The second block:

(012) [email protected]@[email protected]

(021) [email protected]@[email protected]

(102) OZTYSBOOMXGZLODMLNEEOMEVACOOX

(120) [email protected]@NKVMNLUUKMUDYWKKB

(201) UMJNKAUUZLEMXUHZXYGGUZGQBFUUL

(210) [email protected]@YSQZYXOOSZOHNPSSA

Take a closer look at two consecutive lines and see that they tell you how to exchange letters. The letters exchange are stable.

Notice that lines 3 and 4 is very similar in format (notice the stops) to 5 and 6.

Armed with tr, I got variants as: (see the semi-garbled message repeated. you can "fix" this because it is still stable)

(012) JINXUMEDSOZNUOIMFSGYQMPNYYMCDREMXSREO

(021) [email protected]

(102) [email protected]@[email protected]@[email protected]

(120) [email protected]@[email protected]@[email protected]

(201) [email protected]

(210) WHYLOZGVKUMYOUHZCKENRZTYNNZFVQGZLKQGU

and:

(012) OZWYSBOOMXGZLOIMLNEEOMERACOOX

(021) [email protected]@NKRMNLUUKMUIYTKKB

(102) [email protected]@[email protected]

(120) [email protected]@[email protected]

(201) [email protected]@YSQZYXOOSZOHNPSSA

(210) UMJNKAUUZLEMXUHZXYGGUZGQBFUUL

There's also the same for the last row.

This could be a leading hint to some sort of mapping you need to get the real message (this is just noise).

This is ASCII for "RR". (who's he?)

In base 16 it is 1484. (was that an employee id?)

“m” for sure and possibly “c” and “s”

from the lineophon script:

http://www.omniglot.com/writing/linephon.htm

I retain “Ãª” and “r” for sure and "u" as possible match

maybe also “h” from the golem script:

http://www.gregvilk.com/Golem/img/alphabet1.gif

let’s decode “sixteen” using the midle stanza:

we can “draw” 16 using the symbols I, I > and ^, (try to put’em one to one)and if we take the hex corresponding to each symbol we have :

8863 or 8836 (6 = I>^ or 6 = I^>)

we have to separe 1 and 6, so we put 0 as separator:

80863 or 80836

but we have got “BASSE” which means in french “low” so we have to start with the lower symbol(which is >, note that we also have 3 lower than 6)

so our employee ID is : 80836N

Please check this ID, to see if I’m wrong or not(I think I’m not) or let me know how to check by myself.thx

Note: the employee ID at the fermilab is encoded on 5 integers and a caracter (C for Contractor, V for Visitor and N for Employee )

I made some interessting discoveries (the first symbol is the letter 'D' in phoenician alphabet...)

William Basse was also known as a follower of f Edmund Spenser(c. 1552 – 13 January 1599) ho was an important English poet that contribute mainly to the english poetry by his “Spenserian stanza” a stanza construct as this : 8 lines of 10 syllabus verse and the last line is an alxandrin (12 syllabus)

So, we have this:

(012) [email protected]@[email protected]@[email protected]

(021) [email protected]@[email protected]@[email protected]

(102) JDNXUMEISOZNUODMFSGYQMPNYYMCIVEMXSVEO

(120) [email protected]

(201) THYLOZGRKUMYOUHZCKENVZWYNNZFRQGZLKQGU

(210) [email protected]BZPVHOZAEHOS

Let's order it:

(012) [email protected]@[email protected]@[email protected]

(021) [email protected]@[email protected]@[email protected]

(102) JDNXUMEISOZNUODMFSGYQMPNYYMCIVEMXSVEO

(201) THYLOZGRKUMYOUHZCKENVZWYNNZFRQGZLKQGU

(120) [email protected]

(210) [email protected]

You can use this character interchange key to go from one to another sentence in a pair.

A-B

B-A

C-F

D-H

E-G

F-C

G-E

H-D

I-R

J-T

K-S

L-X

M-Z

N-Y

Ã‘- no way you don't have these :P

O-U

P-W

Q-V (from the "garbage" lines, not from the sentences)

R-I

S-K

T-J

U-O

V-Q

W-P

X-L

Y-Y

Z-N

My guess: this is a key reminder, or a key exchange letter. The two "nongarbage" sentences may be a first cypher validation.

Any other thoughts?

You can contact me by leaving a comment in any of my blog articles.

Pity your observation is about a pattern between bit-shifted permutations of the same message...

Which means unfortunately the pattern you noticed doesn't mean anything.

eg,

cipher text is:

khuhvdphvvdjh

I'm going to start rotating through combinations to find the answer:

gdqdrzldrrzfd

heresamessage

ifsftbnfttbhf

jgtgucoguucig

Notice a patter? Making the note that between each of these each char is char+1 isn't really interesting, is it?

It's pretty clear it's a mirror-image picture of the sky, probably in the infrared spectrum (certainly it's not optical as there's a few extra features).

I'm guessing the message was written on a transparent film from an older telescope, but as yet I've been unable to get the image of the sky dated.

I suspect there's an interesting astronomical event in the image, but without a date am at a dead end.

http://www.oldschoolhack.de/tutorials/BiW%20reversing%20-%20CryptoTut%20by%20Basse.htm

The Basse building is interesting as well being that it is 16 storeys tall; perhaps there is some relevance to the lower stories (1 through 7 inclusive)?

I find it hard to believe that this would be a typo given the precision used to create it.

0xCF is right. S stands for swap, swap F with C, employee ID = 207 maybe?

this also goes with chris's comment.

IF Basse means low in french, maybe it denotes that the Hex is LSB, MSB.. i.e. CF(16) = 207 decimal...

If you take that, and turn it into trinary code like the rest, you get a really strange pattern. (replacing letters with zero and numbers with 1, or vice versa)

101 100 101 100 010 010 100 010 011 or

010 011 010 011 101 101 011 101 100

Notice a lot of the groupings are repeated... converting these to letters using the already determined code gives me gibberish though:

JIJICCICD or

CDCDJJDJI

Seems far too coincidental to be ignored though...

Any thoughts on the 87A timestamps that have been found in section 2?