
BleCaliperV4
Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).
BleCaliperV6 is an open-source printed circuit board by Mechanic-Coder, from the Mechanic-Coder/Wireless-Calipers repository on GitHub. It is a 2-layer board of 58.6 × 18.3 mm with 30 parts on 22 nets, routed with 178 tracks and 8 vias.
It is built around the MCP73831T-2ACI/OT-HXY, MMBT3904 and MMBT5401, with the MMBT5551 among its other parts. Its parts include 13 resistors, 3 diodes, 2 capacitors, 2 transistors and 1 IC.
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper). The goal is to provide hardware and firmware examples that let a digital caliper transmit measurements wirelessly (Bluetooth Low Energy) to a host device. Currently the code reads from Vinca calipers (cheap on Amazon). I believe the same hardware could be used on other brands; the code may just need changes to work with different models.
There are three buttons. Data is transferred to the host device (PC or mobile) via Bluetooth Low Energy (BLE) as keyboard presses.
Note: Button-to-pin mappings are defined in Code/BleCaliperRev5/BleCaliperRev5.ino (for example: Send = pin 9, Tab = pin 7, Back/Delete = pin 10). Verify the mapping in the source before wiring.
Resources/. Those files remain under Adafruit's Creative Commons terms; please preserve their license/attribution when reusing.Resources/ for PCB/Eagle files and their license.txt files.*.ino, src/) and open them in your preferred IDE. If you do not find .ino files at the top level, look inside subfolders — some sketches may not be tracked or are stored in Resources/.license.txt files in Resources/ for details.Apologies for the messy layout — this repo is a personal working archive. If there is interest, I may clean and reorganize the project. Open an issue or comment, and I will prioritize cleanup.
This project involves electrical hardware and modifications to measurement tools. Use at your own risk. The repository owner (Mechanic?Coder) and contributors are not responsible for any personal injury, death, loss, or damage to equipment, property, or data that may result from using the hardware, software, or instructions in this repository. Always follow safe working practices, use appropriate protective equipment, and verify designs before powering hardware. If you are unsure, seek assistance from a qualified person.
| Qty | Value | Footprint | References |
|---|---|---|---|
| 8 | R-10K | Resistor_SMD:R_0603_1608Metric | R1, R4, R5, R7, R8, R9, R10, R11 |
| 4 | SW_DIP_x01 | Button_Switch_THT:SW_PUSH_6mm | BackBtn1, ForwardBtn1, PowerBtn2, SendBtn1 |
| 2 | 10µF | Capacitor_SMD:C_0805_2012Metric | C1, C2 |
| 2 | 470 | Resistor_SMD:R_0805_2012Metric | R2, R3 |
| 2 | MMBT3904 | Package_TO_SOT_SMD:SOT-23 | T1, T2 |
| 1 | 10K\ | Resistor_SMD:R_0805_2012Metric | R6 |
| 1 | DIODE | Diode_SMD:D_SOD-123 | D1 |
| 1 | GREEN | LED_SMD:LED_0805_2012Metric | LED1 |
| 1 | JSTPH | Connector_Wire:SolderWire-0.75sqmm_1x02_P4.8mm_D1.25mm_OD2.3mm | batteryGoesHere1 |
| 1 | MCP73831T-2ACI/OT | Package_TO_SOT_SMD:SOT-23-5 | U1 |
| 1 | MMBT5401 | Package_TO_SOT_SMD:SOT-23 | Q1 |
| 1 | MMBT5551 | Package_TO_SOT_SMD:SOT-23 | Q2 |
| 1 | R-1K | Resistor_SMD:R_0603_1608Metric | R12 |
| 1 | R-33 | Resistor_SMD:R_0603_1608Metric | R13 |
| 1 | RED | LED_SMD:LED_0805_2012Metric | LED3 |
| 1 | Screw_Terminal_01x03 | Connector_Wire:SolderWire-0.75sqmm_1x03_P4.8mm_D1.25mm_OD2.3mm | CaliperWires1 |
| 1 | Screw_Terminal_01x10 | Connector_PinSocket_2.54mm:PinSocket_1x10_P2.54mm_Vertical | ItsyBitsy1 |

Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

Mechanic-Coder/Wireless-Calipers
This repository is a working collection of code, PCB/CAD resources, and notes for a Bluetooth-enabled digital caliper project (BleCaliper).

eez-open/psu-hw
EEZ H24005 programmable bench power supply (powered by Arduino Due)

fietser28/EL-Load
The DCL8010 electronic load module features a DC Electronic Load with several modes and protections. This project is the for the development boards for this project. There is a seperate git project for the firmware.



YuaXan/BM3451XXDC-T28A-Board
Rechargeable battery protection board based on BM3451 IC

Bu3nd14/EDA
Scripted analog EDA + PCB automation environment (KiCad 10 + ngspice + SKiDL) for macOS Apple Silicon


It measures 58.6 × 18.3 mm and has 2 copper layers, 1.6 mm thick.
30 parts, built around the MCP73831T-2ACI/OT-HXY, MMBT3904, MMBT5401 and MMBT5551. 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.
From the Mechanic-Coder/Wireless-Calipers repository on GitHub, at the commit this page was made from: the board is Circuit boards/BleCaliperV6/BleCaliperV6.kicad_pcb. PCBKit opens the board in the browser, with nothing to install.
Its repository states no licence, so its author keeps all rights: ask Mechanic-Coder before reusing the design.