2 layers152 × 88 mm
RFBitBangSMT
profdc9/RFBitBanger
A QRP digital transceiver created from readily available parts for off-the-grid maintenance
271 parts222
2 layers57.7 × 107.7 mm
The Ear Tool
HarbinRepairs/The-Ear-Tool14Audible Electromagnetic Interference Detector - Model ET-1
- Size
- 57.7 × 107.7 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 23
- Nets
- 18
- Pads
- 52
- Tracks, vias
- 105, 1
- Pours
- 2
- Routed
- Yes
- KiCad
- KiCad 5 (file 20171130)
- Created
- 26 Mar 2019
- Updated
- 7 Mar 2020
Overview
The Ear Tool is an open-source printed circuit board by HarbinRepairs, from the HarbinRepairs/The-Ear-Tool repository on GitHub, published under the GPL-3.0 licence. It is a 2-layer board of 57.7 × 107.7 mm with 23 parts on 18 nets, routed with 105 tracks and 1 via.
It is built around the LM386. Its parts include 3 connectors, 3 switches, 2 capacitors, 2 resistors and 1 IC.
Main components
1README
README.mdThe Ear Tool
Model: ET-1
Get this kit at our store: http://bit.ly/2TQ3Cbr Or on eBay: https://ebay.to/38sRZv4
License
Harbin Repairs 2020 Creative Commons Attribution ShareAlike 4.0 https://creativecommons.org/licenses/by-sa/4.0/
Documentation
What is the Ear tool?
The Ear tool can be used to detect almost any electromagnetic interference coming from your electronics such as a power supply, transformer, CPU, microcontroller, wireless transmitter, relays, switches, speakers, transducers, transistors and more. At Harbin Repairs we use the Ear Tool to diagnose problems with computer motherboards, cellphones, and televisions by pointing the tool at different parts of a circuit board and listening to the high frequency pulsing coming from different components. For example, this can help us determine if a CPU or microcontroller is doing any processing or if it’s just sitting there burning up because there’s a short somewhere. It can also let us know if a cellphone or other device is turning on even if there’s no sign of life on the screen or lights. The tool can also be used to discover the different noises your electronics make when they are doing different things (e.g. standby mode vs. fully powered on). For the controls, the gain switch adjusts between high and low sensor gain and the full scope switch switch is used to help clear up some of the background noise. More examples are in the assembly guide video below.
Demonstration and kit assmebly guide Video
Bill of Materials
Parts
23| Qty | Value | Footprint | References |
|---|---|---|---|
| 4 | MountingHole_3mm_Pad | Mounting_Holes:MountingHole_3mm_Pad | M1, M2, M3, M4 |
| 2 | LOGO | myFootprints:HR_LOGO_37.4x10.6mm | G1, G2 |
| 1 | 100 | Resistors_SMD:R_0805_HandSoldering | R2 |
| 1 | 10k | Resistors_SMD:R_0805_HandSoldering | R1 |
| 1 | 10k | myFootprints:POT_RV09_HORIZONTAL_WHO9 | RV1 |
| 1 | 220uF | Capacitors_SMD:CP_Elec_6.3x7.7 | C2 |
| 1 | 4.7uF | Capacitors_SMD:C_0805_HandSoldering | C1 |
| 1 | 9V Battery Clip | Oddities:NetTie-I_SMD | P3 |
| 1 | AUDIO-JACK-3F07-TRS | myFootprints:AUDIO-JACK-3F07-TRS | P1 |
| 1 | Full Scope Switch | myFootprints:SW_SPDT_3P_11.1mm_5.5mm | SW2 |
| 1 | Gain Switch | myFootprints:SW_SPDT_3P_11.1mm_5.5mm | SW3 |
| 1 | LED | LEDs:LED-5MM | D1 |
| 1 | LM386 | SMD_Packages:SOIC-8-N | U1 |
| 1 | LOGO | myFootprints:Ear_icon_4.2x4.2mm | G3 |
| 1 | Power Switch | myFootprints:SW_SPDT_3P_11.1mm_5.5mm | SW1 |
| 1 | Sensor Connector | TerminalBlock_RND:TerminalBlock_RND_205-00232_Pitch5.08mm | P2 |
| 1 | Speaker | Oddities:NetTie-I_SMD | LS1 |
The 21 most common of 23 parts.
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Questions
How big is the The Ear Tool PCB?
It measures 57.7 × 107.7 mm and has 2 copper layers, 1.6 mm thick.
What parts does the The Ear Tool use?
23 parts, built around the LM386. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the The Ear Tool KiCad files?
From the HarbinRepairs/The-Ear-Tool repository on GitHub, at the commit this page was made from: the board is Kicad/The Ear Tool.kicad_pcb. PCBKit opens the board in the browser, with nothing to install.
Can I use the The Ear Tool design in my own project?
Its repository publishes it under the GPL-3.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).