Introduction: Amazon Echo Pop Turned Into 1960-ish Science Fiction Talking Computer Terminal
Having watched many science fiction movies over my lifetime, I was a bit disappointed when smart speakers were released in form factors designed to make them inconspicuous. Where were the flashing lights that accompanied Colossus of the Forbin Project fame, the WOPR from "War Games", and the console that Gary Seven used in the Star Trek episode "Assignment: Earth"? I decided to repackage my front-firing new Echo Pop from Amazon into something more suitable (to me).
Supplies
Sound Sensor Module Microphone Light Sensor Controller Relay Delay Switch Module
(available on Amazon by that description, much cheaper on AliExpress or Ebay)
Cookie Tin or suitable enclosure (I used a 10" cookie tin, $1 from a garage sale)
Amazon Echo Pop or smart speaker of choice
12VDC Wall Wart power supply for the LED's and sensor module
3 12V pre-wired Solid Color LED's (Amazon, assortment)
9 Flashing 12V pre-wired LED's (lighthouseleds.com)
Solid color cardboard "Presentation Board" (Hobby Lobby or maybe Office Depot)
3 pieces of Fasade J Trim 0.33-in W x 18-in L Brushed Nickel PVC Tile Edge Trim (Lowes Home Improvement)
(or whatever works for you.....)
Toggle Switch, any type. Only need to use for on/off for a 12V line.
2 two-inch carriage bolts with nuts
Wire
Solder and/or small wire nuts
Hot Glue, RTV Silicone Sealant....
Tin Snips, maybe a hole saw
Drill
Step 1: Build to Your Vision
I had used cookie tins on a few projects in the past and I felt that this project would be easy to build into one. As luck would have it, I found a few at a garage sale the same day I was going to head out to buy one....or a big batch of Danish shortbread cookies in one from Costco. These were $1 each. Score.
This project could really be whatever you choose it to be. A well crafted oak case. A rack mount panel. Something 3D printed (way beyond me).
Once I knew I was working with a round form factor, I played around with various layouts of the elements. An Echo Pop tear down on YouTube revealed that the actual speaker is only 2". So I needed to account for about a 3" cutout for that and then determine how to lay out my LED's.
Step 2: Key Components That Made It Possible
The heart of the project is the sound sensor/relay board. The microphone needs to be as close as possible to the speaker, and the sensitivity set in a way that the speaker sound triggers it consistently and room noise does not. Once triggered, that board energizes a relay that I then use to allow 12VDC to be applied to the LED's. As long as there is sound present, the relay remains energized. After 1 to 60 seconds of silence, the relay de-energizes and the 12VDC is removed from the LED's. I was hoping for that "1 second" as listed in the specs, but in practice the shortest time is about 4-5 seconds.
I had used a very similar circuit board from Futurekit (Sound Switch Controller Delay Time Off Relay 12VDC 10A [ Assembled kit ] available on eBay) in the past to light dials of a few radios with Amazon Echo's inside their cases. In that setting, I like the long delay in de-energizing which allows the dial to remain lit during quiet passages.
Also extremely important in this project is the availability of pre-wired flashing 12V LED's. I quickly learned that making flashing patterns, or even making a single LED flash, is more involved that one might think. These LED's, which have a flash rate of ~1 Hz (once per second) start off as all lit but quickly devolve into randomness. Except my green ones, for some reason (see video). :( So all that was required to make a circuit involving 9 flashing LEDS was wiring them in parallel and applying power and ground. I'm so glad I found these.
Step 3: The Schematic
I decided to use a separate 12V wall wart power supply for the LED's and the circuit card. I might have been able to get away with splicing into the 12VDC produced by the Echo Pop wall wart, but I didn't want to push it.
As you can see, I have three solid LED's and a toggle switch inline in the 12V before it reaches the sensor circuit card. I needed to be able to turn off the LED's. If I was listening to music for an extended period, I didn't want the sensor card to needlessly flip the relay every time music was soft and loud. But I also wanted to be a little playful. I used a white LED to illuminate "Automate Home", the dumb-as-rocks level that is always there. When the switch is thrown and power is applied to the rest of the circuit, yellow "Predictive Logic" and green "Sentience" illuminate and 12V is applied to the circuit card and to the center relay contact on that same card. When the microphone detects a triggering sound level, the relay energizes and the 12V flows to the 9 flashing LED's. A few seconds after Alexa (renamed "Computer") stops talking, the LED's stop flashing.
Step 4: The LED Display
Again, this is an area that can be reworked to suit different visions/form factors. I was limited in my Xacto knife skills, so the panel might look OK from a distance but certainly has room for improvement. I cut the rectangles and lined the back with parchment paper. I had hoped that the translucent nature would allow the LED's to light the rectangles well. That didn't work out, but I eventually came up with a fix for that. Read on.
I used the same black color-through cardboard (presentation board) to build a chamber system for the LED's. Not shown is the top cover that was just a rectangle of the same cardboard that I poked holes in with a nail, I then enlarged those holes to the point where the LEDs snugly fit in the top cover.
You can see I carefully used a hole saw for the speaker cutout. Dangerous on tin. I removed the Echo Pop grill cloth with help from the YouTube tear down video. I hot glued the microphone 'above' the speaker. I used tin snips for the crude rectangle cutout. I had a little more fun with the toggle switch after finding a flip cover at Autozone for <$4. I wired that switch so to 'arm' the AI, you open the cover and toggle it up. When the AI gets dangerous and threatening, it's easy to slam that cover down, flipping the switch. Crisis averted. You can also do that when listening to music, as discussed.
The shape of the Echo Pop (1/2 of a sphere) makes it difficult to mount using hardware, so I just used the RTV silicone sealant to mount it to the top of the cookie tin.
Step 5: Final Assembly / Light Diffusing
I wired everything up the way I had it laid out in my schematic. I used small gray wire nuts where possible, and solder where not. Sometimes both.
I crossed my fingers and applied power to both the Echo Pop and the secondary 12V Wall Wart power supply that I had cut the connector off of and wired into the circuit. Thankfully, no smoke and everything worked just as I planned. The only minor issue, as previously mentioned, is that I do wish the delay for the silence cut-off could be shorter than what I could obtain with the on-board adjustments. Still, it does work as planned.
NOTE: I was a bit surprised prior to fully wiring it up to discover that on the Wall Wart the power line with the gray strip running along it was, in fact, the negative and not the positive line. Thank you, multimeter and my nagging fear.
Ultra Bright LED's are spotlights
One thing I wasn't thrilled with was my rectangles were not lighting up as planned. The LED's, at the close range of about 1/2 inch, produced a spotlight onto the rectangles. The fix I came up with worked well. I took wisps of cotton (small pinches of a cotton ball, teased/spread out). I poked those into the LED 'chambers' with a stick (a Q-Tip with the end cut off). A fairly small amount that resulted in the light being much more diffused and gave a satisfying look to the parchment rectangles.
The Legs
I walked around Home Depot trying to find something appropriate to use as legs or feet to keep the round cookie tin upright. I ended up going ultra cheap: two 2-inch carriage bolts and four 1/4 inch nuts, making them pretty adjustable. I've thought about adding a small bent L-bracket to the back of the tin for a rear support, which would allow the entire device to be off the surface, but the two work well enough.
Step 6: The Final Product (for Now...)
I added the grill cloth by cutting a piece of light cloth the right shape and then poking it into the J channel/cardboard structure with a guitar pick.
Overall, is it what I envisioned? It is certainly close. I could have been neater in my wiring. If I had access to a 3D printer, I could have made a nicer panel and speaker grille. The wording I made for the three solid LED's was done with a clear label maker and taped INSIDE the assembly, facing out. I was going for them looking blank when off and the function only showing when lit. They don't show up nearly as well as I'd hoped, but they are readable in real life.
The joinery of the J channel could have been done correctly with angles, but perfection is the enemy of the good, right?
I'm considering stenciling something on the grille cloth. Maybe a Black Mesa logo, or the Colossus logo, or Apeture Science. Of something of my own design.
I'm happy that I FINALLY have a proper talking computer terminal in my 21st century life.