Volume Control for a Android Head Unit

I gave myself a birthday gift earlier this year.  Upgrading my truck’s cd/tape deck with something more modern.   I installed an Android Head Unit.  For less than $200 and a weekend of work, I gave my 2005 truck modern features such as bluetooth, reverse camera, gps navigation, and mpg gauges.

I have had the android head unit installed a few month now and am still really impressed.  The head unit’s speaker amplifier is a huge upgrade from what I had for sound quality before.  The radio receives stations for longer distances.  I use the bluetooth and reverse camera features daily.  The mpg gauge is done through the Torque app that was preinstalled, and it also has a nice feature of calculating fuel miles remaining.  Cool.

Only complaint that I have about the android head unit is the volume controls, or lack thereof.

When switching between bluetooth and radio sources, sometimes the volume difference is extreme and pressing the small digital buttons on the side of the display is a pain while driving.  There is no way to quickly and reliably change the volume without taking my eyes off the road.  The old radio was great at this, it had a volume knob!

So that’s what I decided to do.  There really isn’t much on the market for usb connected volume knobs.  A few exist, but are out of production or require special drivers.  To be compatible with all versions of android, I needed a volume knob that mounted as a normal usb keyboard.  No special drivers needed.  Don’t fall for the slick design of the Griffin USB/Bluetooth Control Knobs, they require drivers and are not plug-in-play compatible with android.

I was all settled to just make my own usb circuit using this instructable when I redid my initial search for an existing “no driver” usb volume knob.  Adding the “no driver” part and search around google, I actually found a few on amazon for about the same price it would cost me to make one. Around $20.  Deal.

Here are the ones I found while searching that should all work with android.  The device just mounts to the operating system like a usb keyboard.  Plug it into the android head unit’s OTG USB port and it will work right away.

I purchased the DROK unit and it totally worked! Awesome.  Trouble is, I had nowhere to mount the thing on the dash.  It’s HUGE! Around 3-4 inches across, it would look ridiculous mounted on my dash.

Being the hardware modder I am. I took the USB Volume Knob into my workshop and took it apart.  What I found was a lot of wasted space.  The knob pops right off, and the circuit inside is less than 2 inches.  I can work with that.

IMG_0975 IMG_0983

Examining the board, you can see some wasted real estate on the top.  Likely for programming and quality testing.  Holding the board up to the light, I checked the route of traces on both sides.  Traces that just go to the edge of the board and stop are not needed for operation of the circuit now.  I used my dremel to cut off a quarter inch from that side.  Doesn’t sound like much, but made all the difference fitting the circuit in a free spot on the stereo dash assembly.

IMG_0984 IMG_0985

You can see the shaft of the rotary encoder sticking out of the stereo dash assembly on the right hand side. Next step is to find a knob that fits the space, can be connected to a 0.25 inch shaft, and looks classy :)

Volume Controls with a turn of a wheel !!

Update: An unexpected side effect of always having android think that a usb keyboard plugged in, the on screen keyboard does not appear when I select text boxes.  I have a couple of ideas, but it could be as simple as selecting the keyboard fom settings.

Mark 3 Ammo Counter

Nerf, Paintball, Prop Weapons. This is the ammo counter you want~!


The Ammo Counter Mark 3 is a remix of my previous ammo counter design and is now completely reprogrammable by you with no additional tools! There are 10 clip slots in memory, you can easily switch magazine sizes with a single button press. In addition, each clip slot can be reprogrammed by you for any starting value up to 99. Each slot will remember your selected fire mode, semi-auto, full-auto, and count up.

Video tutorial: Coming Soon!

* Smallest Ammo Counter Circuit!
* Selectable Clip Sizes
* Programmable Clip Sizes (Default: 35, 25, 22, 18, 15, 12, 10, 6, 32, 99)
* Programmable Fire Types (Semi-Auto, Full-Auto, and Count Up Semi-Auto)
* Light Break Sensor Ready

Ammo Counter 2017 – New Design

This is a small preview of the new ammo counter design I am working on.  There are two buttons on the face of the circuit that will allow you to select from preset modes, or add your own!  No more hardcoded starting count values!!

More info to follow…


The finished circuit will be about the same size as my previous ammo counters.

A finished one

OTA Antenna FAQs

Here are some Frequently asked questions I get about TV Antennas in my town:

  • What is the best antenna?
  • Can I go bigger?
  • Can I pick up channels from both Madison and Cedar Rapids?

What is the best antenna?

The best antenna is the one that fits your budget. Here is my handout I give folks who ask. I have it broken into three budgets. < $50 / $120 / $200

Can I go bigger?

Short answer, no. Long answer, it depends but probably is not worth it. You can explore this page which describes running multiple DB8 antennas. Midway down the page you will find “Why this 16-bay antenna might not work”. Take a read through.

Can I pick up channels from both Madison and Cedar Rapids?

Again, short answer no. Long answer, maybe. Antennas like the DB8e have multiple elements that can be pointed in different directions. Aside from halving your antennas efficiency by splitting it in two, the next problem is that some of the signal picked up by Side A is then radiated out of Side B. This results in your received signal dropping by more than 50% !
If you are thinking about adding a second antenna to overcome these losses, see above “Can I go bigger?”

OTA Channel List – Aug 2017

I did a scan tonight and found FIVE new channels I wasn’t aware of. If you have an antenna, do a channel scan on your tv to find the new channels. ION, 24/7 PBS Kids, TBD TV, American Sports Network, and QVC.

Here is an updated list of stations from Madison that we can receive in Platteville~! All primary channels are broadcast in 1080i or 720p HD, with the exception of CW, all subchannels are 480i.

3.1 CBS channel3000.com
3.2 MyN mynetworktv.com
3.3 ION iontelevision.com
15.1 NBC nbc15.com
15.2 CW cwtv.com
15.3 Antenna TV antennatv.tv
15.4 Weather weathernationtv.com
21.1 PBS wpt.org
21.2 Wisconsin wpt.org/wisconsinchannel
21.3 Create createtv.com
21.4 PBS Kids pbskids.org
27.1 ABC wkow.com
27.2 Me-TV metvnetwork.com
27.3 Decades decades.com
40.1 Christian kfxb.net
47.1 FOX fox47.com
47.2 Comet comettv.com
47.3 Charge watchcharge.com
47.4 TBD tbd.com
57.1 Independent wi57.tv
57.2 Movies! moviestvnetwork.com
57.3 H&I handitvnetwork.com
57.4 ASN americansportsnet.com
57.5 QVC qvc.com

DaftMike Clone DIY Electronics Kit

This has been a long time coming! ANNOUNCING AVAILABILITY of a DaftMike Clone DIY Electronics Kit !!!!


If you already have a 3D printed case, raspberry pi, arduino, NFC reader, and all you are missing is something to tie them all together. This kit is for you!!

I can answer questions here, by PM, or email thatdecade@gmail.com

Special thanks to Joshua Kane, Jared Kirchgatter, Jason Victoria, Dave Hicks, Ruud Lok, Jeff Moore, and everyone else who helped me debug the design! This kit fixes several issues with the DaftMike’s original design: broken mosfets, non working controllers, and other assembly difficulties.

Assembly Guide is here:

Amazon Fire TV or Roku TV?

I think the Amazon Fire TV will replace my current recommendation for the Roku TV as my favorite “Over The Air” receiver. Just like the Roku TV, the Fire TV will have the ability to pause and rewind live TV.

However, Fire TV adds the ability to pull up a TV Guide. A feature I sorely miss from my cable days and I supplement with a TV Guide app on my phone.

You can checkout the features here:
Fire 55 inch TV: http://amzn.to/2xKWMtw
Roku 55 inch TV: http://amzn.to/2xtrrLb

Ammo Counters – Researching Competition to Push a New Generation

I have been selling ammo counters since 2009. After I made my energy sword, ammo counters were the most requested kit. Over the years, I have probably sold 200-300 kits. Back then, I easily beat out the lame old competition. However, sales dried up last year. I was busy with my EMF and NES projects so I didn’t look into it.

Today, I searched around for new competition. Oh man. Things have changed. I think I still got them beat on size and price, but I need to work on my offerings to stay competitive.

Old competition

New competition

  • Nathaniel Deal: Nerf Ammo Counters
    • Good price for what you get.
    • Offers both bare bones and complete kits. Some kits include 3d printed shells.
    • Mostly focused on nerf builds. Requires additional circuit boards that must be hidden inside your build.
    • ammocounter.com

    Nathaniel Deal: Nerf Ammo Counters

What is most interesting about Nathaniel Deal’s offerings are the complete kits for a reasonable price, the 3D printed shells, and YouTube tutorials.

Comparing Nathan’s Ammo Counter design to my own Ammo Counter design. We both use a custom display board, but mine is much much smaller in size because I mount the microcontroller on the same board as the display. While he uses an off the shelf microcontroller development board (arduino) to run the display over a cable harness and additional shift register / display resistors shield board. That is a lot of extra bulk that he is asking the builder to hide in their project! The additional switches he places under the display are on/off, reset, and clip select. In my Ammo Counter kit, I do away with the need of extra switches by using button combinations to select clip size (hold a dart in front of the light break sensor or hold the fire trigger while also cycling the ammo clip to activate the clip size selection menu).

My own ammo counter design is minimalistic. The size can be fit into any project and does not need any additional circuit boards.
Ammo Counter v3

I love my design so much! However, there are a few things I can learn from Nathan Deal.

  • Create kit listings on Etsy - etsy.com/shop/WestabyElectronics
  • Add a count up mode to my Ammo Counter software
  • 3D printed shells to fit a variety of rail systems
  • Make the light break sensor as a standard option
    • I already do have a light break sensor kit, but I only make them on request.
  • YouTube tutorial videos

MiniNES – Non-NFC Guide

Here is a step by step guide for non nfc builders.

Thanks to Evan and his original work..

MiniNES: Projector

I found an $50 micro projector on ebay that has a USB power output. The 480 resolution is plenty for all the game systems!  Fits perfectly below the MiniNES case!

No automatic alt text available.

I do get undervoltage warnings, but I should be fine as long as I have a clone image to use when my SD card goes corrupt.  Here is the link if anyone wants to take a chance on a “untested” “might be broken” “sold as-is” “no power cable included” projector