Smart Speaker | Amp Teardown and Potentiometer Problem

Here are images of the teardown:

A couple of things to note: I over heated the pads when removing the gain pot and lifted a trace by accident. Instead of soldering directly into the lug hole, I just tied directly to the resistor that is in series with the pot signal.

I also am also not going to be able to use the digital pot I have been working with so far. Note the image that shows the pot with a resistance of 50k, and the one I’ve been working with is 10k.

I’m going to order a pair of these, and many of these to try and solve the bluetooth static problem.

Smart Speaker | Proximity Potentiometer Working Prototype

A direct follow up to this post: https://esologic.com/?p=984


First, here’s a video:

I got the digital potentiometer working! It was very simple using the SPI library built into the Arduino software. All you have to do is address the chip and then write it a value between 0 and 255 to set the resistance value. Here is the code for this version, I’ve cleaned it up a bit since last time:

If you have questions about the code please leave it in the comments.

Smart Speaker | Proximity Potentiometer Proof of Concept

New project! First, here’s a video:

This is the proof of concept for the volume control of the speaker system. In it’s final form, this sensor will be exposed to the outside and will allow users to control the volume without opening the system, preserving the fidelity of the inside. For example, imagine a user is at the beach and wants to change the volume but they have sand covered hands or wet hands. This system will solve that problem.

The sensor is the Sharp GP2Y0A41SK0F. Here are some very very macro shots of sensors inner workings.

But now for what you came here for, the code. It’s very poorly commented as this is just a prototype, but it’s better than nothing. As this project progresses I’ll posted updated versions of this code.

This demo also relies heavily this shift register. I still haven’t decided if i’m going to use a buzzer to interact with the user or if I’m going to use these bar graphs.

Here are some photos of the board if you want to try and work out the schematic:

Ammo Box Speakers | Ordering Parts

It’s summer time and I just got a bunch of money for graduating so the next logical step is make a boom box.

I have already ordered the parts, so here’s my list and an explanation for each part:

Amp – This is the heart of the system. Essentially it’s a small amplifier that will run on 12v. According to the reviews it’s pretty loud. It will take a very standard 3.5mm audio input, or a dual channel analog signal which will be easy to build around.

Battery – Long time followers will know I have a pretty big charger that should be able handle charging this beast. It’s 12v, which is the amp runs on.

Speakers – I picked these mostly because if their compatibility with the amp, and their good reviews on amazon, and the fact that they come with a grill and mounting hardware.

Bluetooth Receiver – This is another “selling point” of the system. Users will play music over Bluetooth. It can be powered via 5v, and I have a spare switching regulator that I can use to power it.

Ammo Box Enclosure – This will house the project. It is big enough, and easy enough to cut into to mount the speakers into the side. It is also sealed, so getting sand in it won’t be that big of an issue for beach trips.

I’ll keep updating as parts come in.