Logic Noise: Ping-pong Stereo, Mixers, And More

July 2, 2015 by Elliot Williams 15 Comments

So far on Logic Noise, we’ve built up a bunch of sound-making voices and played around with sequencing them. The few times that we’ve combined voices together, we’ve done so using the simplest possible passive mixer — a bunch of resistors. And while that can work, we’ve mostly just gotten lucky. In this session, we’ll take our system’s output a little bit more seriously and build up an active mixer and simple stereo headphone driver circuit.

For this, we’ll need some kind of amplification, and our old friend, the 4069UB, will be doing all of the heavy lifting. Honestly, this week’s circuitry is just an elaboration of the buffer amplifiers and variable overdrive circuits we looked at before. To keep things interesting we’ll explore ping-pong stereo effects, and eventually (of course) put the panning under logic-level control, which is ridiculous and mostly a pretext to introduce another useful switch IC, the 4066 quad switch.

At the very end of the article is a parts list for essentially everything we’ve done so far. If you’ve been following along and just want to make a one-time order from an electronics supply house, check it out.

If you’re wondering why the delay in putting out this issue of Logic Noise, it’s partly because I’ve built up a PCB that incorporates essentially everything we’ve done so far into a powerhouse of a quasi-modular Logic Noise demo — The Klangorium. The idea was to take the material from each Logic Noise column so far and build out the board that makes experimenting with each one easy.

Everything’s open and documented, and it’s essentially modular so you can feel free to take as much or as little out of the project as you’d like. Maybe you’d like to hard-wire the cymbal circuit, or maybe you’d like to swap some of the parts around. Copy ours or build your own. If you do, let us know!

OK, enough intro babble, let’s dig in.

Continue reading “Logic Noise: Ping-pong Stereo, Mixers, And More” →

We’re Hiring Contributors And Social Media Masterminds

July 2, 2015 by Mike Szczys 49 Comments

Hackaday has been expanding into all kinds of new areas. We find ourselves stretched a bit thin and it’s time to ask for help. Want to lend a hand while making some extra dough to plow back into your projects? These are work-from-home (or wherever you like) positions and we’re looking for awesome, motivated people to help guide Hackaday forward!

Applying as a Contributor

Contributors are hired as private contractors and paid for each post. You should have the technical expertise to understand the projects you write about, and a passion for the wide range of topics we feature. If you’re interested, please email our jobs line, start your subject with [Contributor], and include:

Details about your background (education, employment, etc.) that make you a valuable addition to the team
Links to your blog/project posts/etc. which have been published on the Internet
One example post written in the voice of Hackaday. Include a banner image, at least 150 words, the link to the project, and any in-links to related and relevant Hackaday features

Applying as a Social Media mastermind

Social Media positions are hired as private contractors. You should have at least some technical understanding of the type of material which Hackaday revolves around. This position has huge growth potential and we’re looking for someone who will keep a social media schedule full and ensure conversations are happening. If you’re interested, please email our jobs line, start your subject with [SocialMedia], and include:

Details about your background (education, employment, etc.) that make you a valuable addition to the team
Links to social media accounts you have driven (this may be your own or a company account)
Two example Tweets and one example Facebook post which have been written specifically for this application

What are you waiting for? Ladies and Gentlemen, start your applications!

Gates To FPGAs: TTL Electrical Properties

June 30, 2015 by Bil Herd 44 Comments

On the path to exploring complex logic, let’s discuss the electrical properties that digital logic signals are comprised of. While there are many types of digital signals, here we are talking about the more common voltage based single-ended signals and not the dual-conductor based differential signals.

Simulated "Real Life" — Single-ended Logic Signal

I think of most logic as being in one of two major divisions as far as the technology used for today’s logic: Bipolar and CMOS. Bipolar is characterized by use of (non-insulated gate) transistors and most often associated with Transistor Transistor Logic (TTL) based logic levels. As CMOS technology came of age and got faster and became able to drive higher currents it began to augment or offer an alternative to bipolar logic families. This is especially true as power supply voltages dropped and the need for low power increased. We will talk more about CMOS in the next installment.

TTL was a result of a natural progression from the earlier Resistor Transistor Logic (RTL) and Diode Transistor Logic (DTL) technologies and the standards used by early TTL became the standard for a multitude of logic families to follow.

Continue reading “Gates To FPGAs: TTL Electrical Properties” →

The Spirit Of Hackaday Shines In Shenzhen

June 29, 2015 by Mike Szczys 11 Comments

Hackaday loves to spread the message of the hardware hacking lifestyle. That’s only possible where there are hardware hackers willing to spend their time getting together to talk the future of the hardware industry, and to celebrate where we are now. We’re honored that you came out en masse for our Shenzhen Workshop and Meetup!

Zero to Product

[Matt Berggren] has presented his Zero to Product workshop a few times now as part of our Hackaday Prize Worldwide series. This spring that included Los Angeles, San Francisco, and ten days ago it was Shezhen, China.

[Matt] leading Zero to Product workshop

Participants designing a PCB

All levels of experience are welcome

We partnered with MakerCamp, a week-long initiative that pulled in people from all over China to build a Makerspace inside of a shipping container. Successful in their work, the program then hosted workshops. The one caveat, Shenzhen in June is a hot and sticky affair. Luckly our friends at Seeed Studio were kind enough to open their climate-controlled doors to us. The day-long workshop explored circuit board design, using Cadsoft Eagle as the EDA software to lay out a development board for the popular ESP8266 module.

Continue reading “The Spirit Of Hackaday Shines In Shenzhen” →

True Random Number Generator For A True Hacker

June 29, 2015 by Voja Antonic 103 Comments

How can you generate random bits? Some people think it’s not easy, others will tell you that it’s pretty damn hard, and then there are those who wonder if it is possible at all. Of course, it is easy to create a very long pseudorandom sequence in software, but even the best PRNG (Pseudorandom Number Generator) needs a good random seed, as we don’t want to get the same sequence each time we switch on the unit, do we? That’s why we need a TRNG (True Random Number Generator), but that requires special hardware.

Some high-end microprocessors are equipped with an internal hardware TRNG, but it is, unfortunately, not true for most low-cost microcontrollers. There are a couple of tricks hackers use to compensate. They usually start the internal free running counter and fetch its contents when some external event occurs (user presses a button, or so). This works, but not without disadvantages. First, there is the danger of “locking” those two events, as a timer period may be some derivative of input scan routine timing. Second, the free running time (between switching on and the moment the unit requests a random number) is often too short, resulting in the seed being too close to the sequence start, and thus predictable. In some cases even, there is no external input before the unit needs a random seed!

Despite what has already been discussed, microcontrollers do have a source of true randomness inside them. While it might not be good enough for crypto applications, it still generates high enough entropy for amusement games, simulations, art gadgets, etc.

Continue reading “True Random Number Generator For A True Hacker” →

Astronaut Or Astronot: Amazingly Engineered

June 26, 2015 by Brian Benchoff 32 Comments

The latest round of community voting in The Hackaday Prize asked a simple question: which project is most likely to save the planet? The results will be posted on Monday.

Now it’s time to see if we’re giving away a $1000 gift card to the Hackaday Store, or just some prizes to people who have voted. The rules here are simple: I’m randomly selecting one person on Hackaday.io. if and only if that person has voted in the latest round of community voting, they get a thousand dollar gift card to the Hackaday store. If the randomly selected person did not vote, I select three people who have voted in the latest round of community voting. For the last few weeks, we’ve been giving out t-shirts. To sweeten the deal, we’re giving away a SmartMatrix, A Simon Says kit, and an Analog Stepper gauge to three people, just because they’ve voted.

Here’s the video:

https://www.youtube.com/watch?v=etBVxy9SvmY

Drat, the Hacker number randomly selected for the $1000 gift card hadn’t voted! Oh what could have been. Don’t let this happen to you next week, VOTE!

To soften the bitterness of defeat we dole out a few awesome prizes to those who had. [xanatos333] gets the Simon Says kit, [sylph.ds] gets an Analog Stepper Gauge, and [dougmsbbs] gets a Smartmatrix. Thanks to those who voted, and be sure to vote in the next round:

NEW ROUND OF VOTING

We’ll have to do some math and run a few scripts to figure out which projects the Hackaday.io community deemed most likely to save the planet. Until we put that data together, it’s time to start a new round of voting. This week, we’re looking for projects that are Amazingly Engineered.

Next Friday we’ll select a random person on Hackaday.io, and if they have voted, they get a $1000 gift card! For the apathetic non-voters… nada.

Prize Alert: Submit By Monday For Chance At Hundreds

June 25, 2015 by Mike Szczys 9 Comments

For the past two weeks we’ve been on the lookout for the best 2015 Hackaday Prize entries which are using parts manufactured by Atmel, Freescale, Microchip, and Texas Instruments. All four are sponsors of this years initiative to solve problems faced by a large number of people.

The three-week mini-contest will come to a close on Monday and the Hackaday crew will begin to assign 200 prizes to the entries; 50 for each of the curated lists. Prizes include Mooshimeters, DS Logic Analyzers, Stickvise, Bluefruit BLE Sniffers, Cordwood Puzzle kits, and TV-B-Gone kits.

There are two things you need to do in order to be considered for this contest: make sure your project has been submitted as an official 2015 Hackaday Prize entry, and that the project is listed on the list associated with the parts manufacturer you’ve used in your project design. The easiest way to get on the list is to leave a comment on the .Stack thread.

You can check to ensure you’ve met these two requirements by viewing your project page and looking in the left sidebar. The square thumbnail photo at the top will have a black flag with the astronaut logo at “2015”. Below that you will see banners for the lists on which your project is included. You should be on at least one of the following lists: 2015 THP: Atmel Parts, 2015 THP: Freescale Parts, 2015 THP: Microchip Parts, 2015 THP: Texas Instruments Parts.

Don’t miss out on this stage of the contest. You stand a really great chance of being selected as a winner! And for those already on the lists we can offer some advice for rising to the top. Polish up your documentation. Tell us how the parts are used in your design, where you are in the prototyping process, and list the tasks you have yet to accomplish. Share the whole story of what you’re working on. Good luck!

Those looking to discover and be inspired by the existing entries should give Astronaut or Not a try. The side-by-side comparisons are a great way to browse, and could also win you some prizes.