Welcome to the second issue of BitPunk.FM, your lo-fi audio zine with a mix of cypherpunk, music, poetry, culture, and more.I'm the editor, Josh Dadko, and this issue titled Your Results May Vary is coming out just before BTC Nashville in July 2024.
Let me run down the track list for you because I'm pushing the ends of this 40-minute tape Once I'm done talking, we have a high energy track by Camillo to kick things off.
Then I have a techno historical article for you on analog voice encryption with a fun piece of software to try.Closing outside day, I have a poem.I went full out on this poem.
It's the first four of nine stanzas of a poem called Ode by Arthur O'Shaughnessy written in 1873. but I wanted a kind of 1960s beat poetry vibe, so I read and set the poem to Smooth Bossa Nova, arranged by Jeff Lewis.
Going one step further, after a 25-year pause, I played the trumpet solo.I wanted it to be in one take, but I did punch in once.After only one week of practicing, I'm happy with it.
But if you don't like it, consider it your invitation to submit your own beat poetry. Side B starts rolling with a creative remix of a public domain U.S.Army film.
The thought running through my head when I made this was, I think everyone today would agree that this is government propaganda from the 1950s.
But what things are said today that in 70 years will people look back on and go, oh, that was clearly government propaganda in 2024? Following this, we have a beautiful vocal and piano piece from the Czech artist Beretta.
Closing out the tape, I will send you a Cashew token over QR over audio.Thank you to all the listeners and community out there.I really enjoy making crazy audio content for all of you, but you are invited to participate as well.
If your contribution makes the issue, I will reserve a tape for you.Go to bitpunk.fm contact for more details.And with that, let's get the second issue rolling.I hope to see you in Nashville.
I recently thought to myself, self, wouldn't it be nice if I could speak into my microphone and record myself the tape, but with encryption?And keeping with the spirit of cassettes, it'd be even better to do this in an offline and analog way.
Well, this led me down quite a rabbit hole of analog audio encryption history and techniques.So in this article, I'd like to give you a tour of audio encryption and leave you with a fun piece of software to try.
I tried to find the first example of encrypted audio streams.I think I found it.And the story is quite a trip.But let's get back in that way back machine.
In World War II, the American president and the British prime minister wanted to talk, probably about how to create the new world order and how annoying a gold standard was because they couldn't control the money supply.
But who knows what elites talk about?In any case, they wanted to chat.And while there was an underwater transatlantic cable at the time, As far as I can tell, it was limited to telegraph messages, not voice.
So the user experience for FDR and Churchill was basically they pick up a special phone, this encryption piece happens, and their signal is sent over HF radio to the other end.
It was a full duplex system, meaning they could talk and listen at the same time.This was the first secure voice system that was built in 1943.This was called SIG Sally. Okay, but how does it work?
Well, even in 1943, they recognized that the first step should be to digitize analog voice and then encrypt it in the digital domain.First, they use a vocoder.
The purpose of the vocoder was to prepare human voice for digitization through a kind of synth effect.You've heard this effect before in music.
This is a sample of four songs from Earth, Wind & Fire, Kraftwerk, Michael Jackson, and Daft Punk using a vocoder. A vocoder takes two inputs, a modulating signal and a carrier, and produces an output signal.
It does this by first splitting the modulator into channels.Each channel is a bandpass filter isolating part of the frequency from the rest.Sig Sally had 10 channels of bypass filters plus 2 side channels for a total of 12.
You can think of these channels as dials on your EQ. The vocoder then modulates each channel onto the carrier in its specific frequency range.For human voice, this produces that famous robot voice.
But we aren't done yet, because we still have an analog signal, not a digital one.So SigSally had these 12 channels, and each one was quantized on an amplitude scale of 0 to 5 or 6 bits.
That means at any point in time, the amplitude of the channel was represented by a digit from 0 to 5.So if you had a signal represented as 0, 1, 2, 3, 4, 5, 4, 3, 2, 1, 0, that signal's amplitude rises and then falls.
This is similar to what we call today Pulse Code Modulation, or PCM, and appears to have been invented for SigSally.OK, so now we have digital data so we can encrypt it.
This is where things get real, because at this point we have 12 channels digitized into six bits each, each producing a stream of data.The following is the most hipster way of encrypting data I've ever discovered, and I want to tell you how it works.
Okay, essentially the cipher they used is a one-time pad construction.So what you do is you take the quantized data, add the random data, which is also quantized in six bits, and then apply modulo six.I'll give you an example.
So if the original data was a zero and the key is one, the ciphertext is simply just one.You just add a one.If the original data is four and the key is four, Well, the encrypted data is two, and this is because four plus four is eight.
But of course, we apply the modulus of six.And so essentially there's two digits left over after six.That's what modulus is.And the result is two.Now, if you did this in a text based one time pad, it would be a modulus 26.
So, for example, what that would mean is that after Z, you just wrap back to A. Okay.Now for one time pads to work, both parties have to have the same copy of the key.Now here's the mind blowing part.Okay.
The key data, which was used to secure SIG Sally and subsequently all transatlantic communication was stored on a vinyl record. That's right.They even use precise turntables.I mean, honestly, this is amazing.
So each record held about 12 minutes of the key stream.And then there was two turntables.So a second turntable could queue up the second, the second record in case these elites were talking too much.
OK, now there is a small problem of time synchronization.The key stream in the US must be applied to the key stream in the UK at the same time, meaning the key records must be started at the exact same time and position on the record.
Even more, these records had to be produced exactly the same. This was prior to atomic clocks, mind you, which were invented in the late 1940s.
So once started, the turntables themselves had a whole system to stay in sync based on the feedback of codes encoded in the key record and then various speed measurements on the turntable itself.Okay, we're nearly there.
At the end of the encryption phase, we've got 12 6-bit channels properly encrypted.But how to send them over the radio?Well, if you listen to issue 0 of BitPunk FM, you should know the answer.They used Frequency Shift Keying, or FSK.
In this case, MFSK, because they had six tones, one for each bit.So now there are 12 channels that were finally sent over HF radio simultaneously, where the entire process I just described was reversed.
Okay, now why did I describe all of this besides just being a fascinating piece of history?And why was this procedure invented?Because the much simpler way of doing this is not secure at all, as we will see now.
The naive approach, which is still in use today, especially on cheap walkie talkies and ham radios, is to use frequency inversion.Frequency inversion takes the lowest frequency and it becomes the highest and vice versa.
This might sound complicated, but let's try this approach on text, for example.So if we were to take the English word water, W-A-T-E-R, and apply the frequency inversion kind of algorithm, it would produce R-E-T-A-W, or retaw.
So it might sound complicated, but it's really not.So let's hear a sample. So this is basically XOR or ROT13 for audio, because the same transformation scrambles and de-scrambles audio.Like I said, it was, is quite popular, however.
One of the authoritative books on video and audio scrambling is European Scrambling Systems by John McCormick.
It has a black and white picture of the Earth on the cover, and underneath that, the skull and crossbones with the subtitle, The Black Book.So judging from the cover, you know this book will be good.
The book goes into great detail about smart card hacking and pay TV hacking.It briefly mentions audio inversion. But comments that a more effective way of preventing the pirate audio from being captured was just to blank out the sound.
So it didn't have that much use.Instead, the focus was on encrypting satellite TV images and video.It's a super interesting book, though, and I highly recommend it if you want to get into all the technical details of cracking pay TV.
Okay, but now let's try to unscramble our audio.For this, we're gonna need a tool called Deinvert, D-E-I-N-V-E-R-T, which is on GitHub at Windytan Deinvert, that's W-I-N-D-Y-T-A-N.
Unfortunately, it's a C-based AutoTools project, so you're gonna have to get on a Linux machine and crack your knuckles to compile it, but I didn't have any issues on Ubuntu 20.04.
Once built, you simply run the program with the input audio file and provide an output file name for the output.How to reverse the process?Well, just swap the input and output.When I do this, we recover the following audio.
The Times, 3 January 2009, Chancellor on brink of second bailout for banks.There are more advanced ways to scramble the audio, for example, picking different frequencies to rotate around, but it is still easily reversible.
Perhaps the only use case is if you had some sort of short-lived tactical information and wanted some way to send it obfuscated.But anyone with a cassette recorder who captures the audio will be able to decode it back in their lab.
Okay, I will leave you with a slightly harder one to disgramble on your own. So despite the ease of analog methods, for security purposes, it's best to digitize the audio.
So maybe one day I'll get around to building this inline encryptor, but when I do, it'll be in the guitar pedal form factor. Lastly, I want to thank cryptomuseum.com, which had the original article on how SigSally worked.
If you want more technical information, especially pictures of how all the mechanisms work, I recommend you go to the website cryptomuseum.com.
I was certainly the inspiration for this article among a launching point for other research in the SigSally.So a big shout out to cryptomuseum.com for providing such a great technical article.
How are you sorry that I'm not at home?But when I get the message on my telephone, you'll be the first one on my list.
Crazy Calls, a tape of seven different songs and funny recordings for answering machines.
I am very sorry that I'm not at home to take your call.I'll be 1495 when I will get right back to you.Leave your message, leave your message at the door.
Give someone the gift of gab for their answering machine.
What you've actually done is bought a one-way ticket to the answering machine zone.
Nobody's home.Nobody's home. I'm glad you called, but I'm not home.But I'll be back before too long.
Crazy Calls.A tape of seven different songs and funny recordings for only $14.95.Wait for the beat.
You gotta leave your name, you gotta leave your number.Wait for the beat.Call 1-800-351-5200.I'll call you back when I get home.
We are the music makers and we are the dreamers of dreams.Wandering by lone sea breakers and sitting by desolate streams.World losers and world forsakers on whom the pale moon gleams.Yet we are the movers and shakers of the world forever it seems.
With wonderful, deathless ditties, we build up the world's great cities.And out of a fabulous story, we fashion an empire's glory.One man with a dream at pleasure shall go forth and conquer a crown.
and three with a new song's measure can trample a kingdom down.We, in the ages lying, in the buried past of the earth, build Nineveh with our sighing and babble itself in our mirth.
and overthrew them with prophesying to the old of the new world's worth?For each age is a dream that is dying, or one that is coming to birth.A breath of our inspiration is the life of each generation.
A wondrous thing of our dreaming, unearthly, impossible seeming. The soldier, the king, and the peasant are working together in one.Till our dreams shall become their present and their work in the world be done.
What is it?What strange manner of reasoning brought it about? What false hope is symbolized by the clenched fist?Countries blinded by false propaganda, unable to see the truth until it was too late.They ruthlessly began wiping out all opposition,
The control of the state is placed in the clenched fist of the few.The voice of the many is silenced. The thought channels of the students in the universities are molded into a standard pattern.
They are told what they must study and held to it by inflexible discipline.They do not question.The professors in the universities are not searchers after truth.
They are puppets, mouthpieces for a political machine, teaching what they are told to teach, using textbooks selected by their masters.They do not question.
These are not free-thinking scientists following a path of experiment and deduction, regardless of where it may lead.They are skilled robots, told what to think and how to work, and the nature of the conclusions they are to reach.
A man's home is not his castle.He does not have the inalienable right to own a home.He is never free of the searching eye of the secret police.You need a permit to change your residence or to take a casual business or pleasure trip.
They do not question.What becomes of artistic expression that must be subverted to state control? You crush out the divine spark of religion, and you have the dark, godless society of statism.
The radio, statist style, is the echo of the master's voice.A free press is non-existent, and other information sources are dominated by the government.You get propaganda pellets, pre-digested
In a society where state spies check every move of the citizens and report to a central agency, how can a human being sleep at night? Ye shall know the truth, and the truth shall make you free.
The gyrations of these puppets are menacing and dangerous.It is their job to pour out an endless stream of printed propaganda.
They picture the police, the FBI, and other law enforcement organizations as suppressors of the masses, rather than as protectors of our way of life.
The security of the United States government demands a constant check on suspected government employees and the machinery to bring them to trial if necessary.As J. Edgar Hoover has stated, don't confuse liberals and progressives with statists.
Don't label anyone as a statist unless you have the facts. In recognizing a statist's physical appearance counts for nothing.If he openly declares himself to be a statist, we take his word for it.
If a person consistently reads and advocates the views expressed in a statist publication, he may be a statist.
If a person supports organizations which reflect STATUS teachings, or organizations labeled STATUS by the Department of Justice, she may be a STATUS.If a person does all these things over a period of time, he must be a STATUS.
One thing at least is true of STATUS.They never sleep. Freedom-loving peoples all over the world stand alert to the menace of statism.They are uniting in defense of individual rights for men.
Lead in this defense, for we know the value of freedom in terms of freedom of worship. Enlightenment of the mind.The right to learn the true values of life undistorted.The right to freedom of speech without fear of oppression by state police.
The right to move from place to place at will. Freedom-loving people all over the world have sworn eternal hostility toward any form of tyranny over the mind of man.
The usual, sir? Even after 500 plays, our high-fidelity tape still delivers high fidelity.Accel.It's worth it.
I'm disappointed, I'm disappointed when I know that your hands are burning differently.I'm disappointed, I'm disappointed when I know that I won't be able to do my job.
You could have everything you wanted, you had a spark in your eyes, at least from the beginning.And then you told me the same thing, forget it, we're probably at the end of the line.
I don't want to believe that it was all just a dream, I don't want to be the bad one, and you say I am.And my love is tormenting me, so come back to me, I'm asking you.
Sklamaná jsem, sklamaná Náručtvá je něžná Sklamaná jsem, sklamaná Že jsem jen holka běžná Nemám důvod dýchat
Když mi srdce vzal, za tebou nejdem neposmíchat A přesto ztracená a zamatená, jdu dál Zamilovaná a tu bolest tu jsi mi dál A všichni chrámy z lásky ukrývám
Sclamanai sounds, Sclamanai Sclamanai sounds, Sclamanai
Get into my Commodore 64!My friends are knocking down my door!
So get into my Commodore 64!It's mind-boggling!Commodore 64 lets you play hundreds more games than any video machine, plus draw, program, even do music!I'm more alive than ever before!
And my friends are knocking down my door!
We're into our Commodore 64!
Since this tape sign has a kind of 80s feel with the cassettes and the ads and all that, let's talk about another 80s technology that is making a comeback.I'm talking about eCash.
In 1982, David Chom published the paper, Blind Signatures for Untraceable Pavements.I would like just to read the introduction of this paper as it motivates the use case even today.
Automation of the way we pay for goods and services is already underway and can be seen by the variety of growth of electronic banking services available to consumers.
The ultimate structure of the new electronic payment system may have a substantial impact on personal privacy as well as on the nature and extent of criminal use of payments.
Ideally, a new payment system should address both of these seemingly conflicting sets of concerns.
Ultimately, this idea was not successful in the marketplace at the time, and DigiCash, the company David Chom founded to market this idea, filed for bankruptcy in 1998.
In a Forbes article, Requiem for a Bright Idea, published November 1st, 1999, the reporter asked David why he thinks this idea did not take off.He said, Merchants and banks were lukewarm.
They covet the customer data they collect for targeted marketing.Consumers were unmoved.As the web grew, the average level of sophistication of users dropped.It was hard to explain the importance of privacy to them.
But this idea is having a bit of a comeback, perhaps just like cassettes. For example, there is now a GNU project implementing this idea called GNU TALOR.I'll read some user reviews of GNU TALOR which I found on its own website.Review number one.
In my opinion, for those of us who aren't anti-government, TALOR represents an ethical future of digital spending.From a Hacker News user.Review number two.
As far as I understand it, Taller seems to be great for privacy in society, ensuring income is taxable.Governments can't see how you spend your money, but they can see who receives payments.
Bitcoin and others will never succeed because they are too friendly towards illicit behavior.Taller seems to strike a genuinely interesting and ethical balance here.From a user on Hacker News.Review number three.
This is the most political open source project I've seen in a while.I love the idea that it's designed to sit inside a progressive society where we all agree we have a social contract to the state.That is very different to a lot of similar efforts.
And at the very least, it's an important part of the discussion.Right now it's vaporware, but I'm very interested in its release, says a user from Hacker News.Based on these reviews, I have no further questions about the new Taller.
Now, there is an alternate project called Cashew.The website is cashew.space.The primary difference is that Cashew is a Chamian e-cash protocol, but backed by Bitcoin, specifically Bitcoin's Lightning Network.
So the marketing pitch for Cashew is that you have all the benefits of quick payments, low transaction fees, both of these thanks to Lightning, and the privacy features of e-cash. But what about the cons?
Well, to accomplish this, you need a semi-trusted third party, which Cashew calls a mint, which essentially swaps e-cash tokens for lightning sats.To be fair, this is not a specific problem to Cashew, but to e-cash in general.
Now, there's lots of descriptions online, and it's quite popular right now in the podcast echo chambers to discuss Cashew.So I'm not going to, as chat GPT would say, delve into this topic right now.
Instead, I want to focus on one interesting aspect of Cashew, which is how eCash is transmitted from one party to another.This is from the Cashew website.
Cashew transactions happen out-of-band, which shifts the responsibility to use secure channels for sending tokens.The most secure channel is to send tokens air-gapped via QR codes, since it doesn't leave any trace of out-of-band data.
If tokens need to be sent over a network, it should always be done over an end-to-end encrypted channel, preferably with self-destructing messages. So Cashew recommends we use a QR code to transfer these tokens.
So I would like to send you now an e-cash testnet token encoded as a QR code over audio.Okay, now Josh, please explain how you will send an image to me over audio.Well, I am glad you asked.
I'm going to play some audio that represents a transmission of a slow scan television or narrowband television.
It works very much like analog TV signals, except it was designed for ham radio where the bandwidth is three kilohertz versus analog TV signals, which were six megahertz.Therefore, it is much slower as you will soon see.
FlowScan Television, or SSTV, uses the rasterization method that Analog TV uses.Rasters are just a table of pixels, so think of it like a bitmap, which means we'll be sending the data pixel by pixel.
What you'll hear is a synchronization tone for the start of the image, and then there's some header information. I'll be using a mode called PD90, which has a resolution of 320 by 240 pixels.
Each line is called a scan line, and each line contains essentially a header, the bits of the pixel, and a footer.
Except the header and footer are synchronization pulses, which aren't used in ham radio, and we'll discuss the implications of this later.
For each pixel, there's kind of an audio frequency shift keying where for black and white images, a zero might be at 1300 Hertz, a start bit 1200 Hertz, and a one would be at 1100 Hertz.
Our image is technically sent in color, but I won't get into the color encoding now, but suffice to say there are different frequencies to represent different color data.
The experience for you is that it'll look like kind of a fax showing up on your phone.If you'd like to try this, download the Robot36 app, which is also in the F-Droid repository, as well as the Google Play Store.
Pause the tape if you need more time.Open the app and it'll begin listening.You'll see some colorful static appear.
The app should auto-detect the incoming signal, but if it doesn't, click the hamburger menu, go to the lock mode, and pick PD90 and try again.
If you have an iPhone, there is an app called SSTV Slow Scan TV by Black Cat Systems, which is ranked number 33 in the lifestyle category.But I didn't try it, so this is reason enough to get an Android.
Remember that I mentioned that Ham Radio ignores the horizontal sync pulses?Well, it's assumed that time is constant over the air, which is largely true for Newtonian physics, I think.
Unfortunately, the physics of cassettes is different because of wow and flutter, so you may experience an effect like the cover of this cassette where the lines distort and skew. You might not be able to recover the QR code in this case.
You can and should try to calibrate your cassette deck's speed and azimuth, perhaps.I did this on a few cassette decks.Some worked better than others.Your results may vary.
In any case, there's a digital version on bitpunk.fm if you want to use that with a high degree of success probability.OK, I will now play the transmission and finish out the tape.It will be almost two minutes.
What you should receive is an image of the QR code that encodes a Cashew token.If you can Base64 decode the token after stripping off the Cashew A header, you get JSON and then you'll know you have a good copy.
The best part of Cashew tokens over QR, over audio, over cassette, is that you can even meet the self-destructing suggestion.You can, by yourself, take a strong magnet and immediately erase the tape, wiping the evidence of the transaction.
So I will say farewell to you now, dear listeners.Expect the next issue in October.I hope you enjoyed this issue with the technical articles, music, and other sonic delights.Please consider submitting some audio for the next issue in October.
You can even hit me up on Noster, on BitPunk FM, npub1F49, colon VQVLZPEZ. I suggest if you aren't going to try this experiment to stop listening now as it will be not so pleasant on your ears.In 3, 2, 1, go.
I'm sorry.I'm sorry. Oh, I'm sorry.
