Category Archives: News

Updates to the Hallmark Card Teardown Article!

Smaller pics and better descriptions!

Hallmark Innovations Voice Recorder Card - Inside

Behold! Once the card is open, a slider tab is pulled and the card is activated. Whatever message that was recorded play!

Hallmark Innovations Voice Recorder Card - The Project

Once the circuit assembly has been CAREFULLY removed from the card, this is what you’re left with. There’s an electret microphone for recording, a small toy speaker, a wired switch, and the motor-gear assembly. The PCB is also interesting…

New Hallmark Sound / Voice Recorder Card Teardown Article!

I got a birthday card from my dad for my birthday and noticed that it had a voice recorder circuit inside.  With a signal amplitude-activated motor and simple electret microphone + amplifier + loudspeaker assembly, there are tons of applications.  Visit the link below to check out the progress (busy, busy busy!) and there will be more info on what you can do with it.


Site Under Construction – Content’s On The Way

Hello, World!

This site is currently under construction, but will have tons of great original content with DIY audio electronics in mind.  Circuits, schematics, tutorials, how-tos, a video series, and a whole lot mroe a re in the works.  In the meantime, check out some of the links on the right and shoot me an email – any suggestions that you have will make a huge difference!

Here’s what’s coming up:

– CMOS Basics – the Lego of the Electrical Engineering world, CMOS is simple to use and fun to build with.  They’re also a great place to begin building your own circuits!  Breadboarding, schematic reading, prototyping… a multi-part series with a ton of circuits to play around with!  I’m excited!

CMOS 4017 Based 8 Step Sequencer – I’ve scoured the Internet, posted on forums, breadboarded like a madman, and did my homework in a quest to come up with the best CMOS based sequencer I could make with.   8 Step, 16 step, clock in, clock out, gate, s-trigger, adjustable CV, multiple CV outputs, manual step, hold, cascading sequencers, randomizing – see what we’ve got so far, check back daily for new updates!

– Replacing your guitar’s input jack – a step-by-step guide to solve one of the most common and easiest-to-fix guitar-related problems.  Most guitar shops charge way too much for this simple repair that you could easily do yourself.

– Make Your Own S-Trigger Cable – Older synthesizers have a funny looking input jack on the back.  Find out what’s actually going on and build your own S-Trig cable for cheap!

– Dissecting the DS-8 Analog Drum Synth:  In this series of posts, we’ll be taking an in-depth look at this popular synthesizer’s schematic.  We’ll chop it up into manageable parts, figure out what’s actually going on, and put it all back together.  Of course, we’ll also figure out how to modify the circuit to venture into some uncharted audio territory!

– 3PDT / DPDT Stomp Switch True Bypass – What true bypass actually is, the internals of these switches (i’ll be sacrificing one of each in the name of DIY science), common wiring schemes, problems you’ll encounter (switch pop, LEDs), and how to true bypass.  Simple and easy!

– White Noise Generator with Filtering – One man’s noise is another’s music!  At the beginning, you’ll think, “that’s not supposed to be connected like that!”  By the end of this post, you’ll see just how right wrong can be!

& much, much more!  Check back daily!