
SF 01 Compute Board
sandgum/Triangulate-SF_01-Speaker-Frame
A 24 inch Raspberry Pi-based Android digital picture frame attached to a 220W stereo Bluetooth speaker with DSP

HGA22 Time Signal Receiver
UNO HGA22 V1 is an open-source printed circuit board by koszozoltan, from the koszozoltan/HGA22 repository on GitHub, published under the MIT licence. It is a 2-layer board of 35.6 × 53.3 mm with 63 parts on 38 nets, routed with 205 tracks and 20 vias.
It is built around the MCP6476U-E/OT, LP5907MFX-3.3 and LP5907MFX-4.5, with the BSS138 among its other parts. Its parts include 27 capacitors, 16 resistors, 4 ICs, 3 connectors and 1 transistor.
HGA22 Time Signal Receiver This project is used to receive and decode the time signals broadcasted at 135.6 kHz by the HGA22 transmitter station in Lakihegy. The system is capable of processing phase-shift keying (FSK) signals and extracting time information.
https://github.com/5an2i/USB_HGA22
📋 Features Frequency: 135.6 kHz (LF band)
Modulation: FSK
Platform: STM32C071 Nucleo Data format: Serial, RNDIS USB - NTP 🛠️ Hardware architecture The following components were required for reception:
Antenna: [Ferrite rod or RFID reader antenna] tuned to 135.6 kHz.
HGA22 Time Signal Receiver Ez a projekt a lakihegyi HGA22 adóállomás 135,6 kHz-en sugárzott pontos idő jeleinek vételére és dekódolására szolgál. A rendszer képes a fázismodulált (FSK) jelek feldolgozására és az időinformáció kinyerésére.
📋 Jellemzők Frekvencia: 135,6 kHz (LF sáv)
Moduláció: FSK
Platform: STM32C071 Nucleo Adatformátum: Soros , RNDIS USB - NTP 🛠️ Hardver felépítés A vételhez az alábbi komponensekre volt szükség:
Antenna: [Ferrit rúd vagy RFID olvasó antenna] 135,6 kHz-re hangolva.
Frekvencia: 135,6 kHz
Adatsebesség: 200 bps (Baud)
Szerepe: Alternatíva a német DCF77-re, de nagyobb adatsebességgel és gyakrabban küldött időinformációval rendelkezik (akár 10 másodpercenként).
Shift (löket): ±170 Hz
Frekvenciák: * F_low: 135,430 kHz (Space / 0)
F_high: 135,770 kHz (Mark / 1) A vevő dolga, hogy eldöntse: éppen melyik frekvencia „szól”.
Miért jobb, mint az FFT? Mivel nekünk csak két konkrét frekvenciát (a löket alatti és feletti értékeket) kell figyelnünk, felesleges a teljes spektrumot kiszámolni. A Goertzel sokkal gyorsabb mikrokontrolleren.
A kódunkban két Goertzel szűrő fut párhuzamosan. Amelyik kimenetén nagyobb az „energia” (amplitúdó), azt a bitet tekintjük érvényesnek.
Start karakter: 0x68 (ez jelzi a csomag elejét).
Hossz: Megadja, hány bájt következik.
Ismételt Hossz és Start: Biztonsági ellenőrzés.
Címzés: Megadja, kinek szól az üzenet (az időjel címe általában 0x00).
Adat (Payload): Itt van a lényeg! BCD kódolással tartalmazza az évet, hónapot, napot, órát, percet és másodpercet.
Checksum (CRC): Hibaellenőrzés.
Stop karakter: 0x16.
A kódban (main.cpp): A parsoló egy állapotgépet (State Machine) használ. Addig dobálja el a bejövő bájtokat, amíg nem talál egy 0x68-at, majd elkezdi feltölteni a puffert a megadott hossz alapján.
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
| Qty | Value | Footprint | References |
|---|---|---|---|
| 8 | 100n | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C6, C7, C9, C10, C11, C12, C13, C14 |
| 6 | 100p | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C8, C22, C23, C24, C25, C26 |
| 6 | 1k/1% | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R4, R6, R11, R12, R13, R14 |
| 6 | 1n | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C16, C17, C18, C19, C20, C21 |
| 5 | 1M/1% | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R1, R2, R7, R8, R10 |
| 4 | 1u/16V | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C1, C3, C4, C5 |
| 4 | SolderJumper_2_Open | Jumper:SolderJumper-2_P1.3mm_Open_TrianglePad1.0x1.5mm | JP1, JP2, JP3, JP4 |
| 2 | 100/1% | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R5, R9 |
| 2 | Fiducial | Fiducial:Fiducial_1.5mm_Mask3mm | FID1, FID2 |
| 2 | MountingHole_3.2mm | Arduino_MountingHole:MountingHole_3.2mm | MH3, MH4 |
| 1 | 100k/1% | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R16 |
| 1 | 100u/6.3V/TAN | Capacitor_Tantalum_SMD:CP_EIA-3528-21_Kemet-B_HandSolder | C2 |
| 1 | 10k/1% | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R15 |
| 1 | 10n | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C27 |
| 1 | 10p | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C15 |
| 1 | 125kHz RFID Loop Ant | Connector_PinHeader_2.54mm:PinHeader_2x01_P2.54mm_Vertical | JANT1 |
| 1 | 30k/1% | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R3 |
| 1 | Analog | Connector_PinHeader_2.54mm:PinHeader_1x06_P2.54mm_Vertical | J3 |
| 1 | BSS138 | Package_TO_SOT_SMD:SOT-23_Handsoldering | Q1 |
| 1 | Digital/PWM | Connector_PinHeader_2.54mm:PinHeader_1x08_P2.54mm_Vertical | J4 |
| 1 | Fiducial | Fiducial:Fiducial_Cross_1.5mm_Mask2mm | ORIG1 |
| 1 | LM321LV | Package_TO_SOT_SMD:SOT-23-5 | U2 |
| 1 | LP5907MFX-3.3 | Package_TO_SOT_SMD:SOT-23-5 | U3 |
| 1 | LP5907MFX-4.5 | Package_TO_SOT_SMD:SOT-23-5 | U4 |
| 1 | MCP6476U | Package_TO_SOT_SMD:SOT-23-5 | U1 |
| 1 | Power | Connector_PinHeader_2.54mm:PinHeader_1x05_P2.54mm_Vertical | J1 |
The 61 most common of 63 parts.

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wemaxon/esp32-audio-streamer
Hardware design for a WiFi/Bluetooth audio streamer using the esp32 microcontroller and the PCM5102A DAC, intended to be used with squeezelite firmware.
It measures 35.6 × 53.3 mm and has 2 copper layers, 1.6 mm thick.
63 parts, built around the MCP6476U-E/OT, LP5907MFX-3.3, LP5907MFX-4.5 and BSS138. 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 koszozoltan/HGA22 repository on GitHub, at the commit this page was made from: the board is hardware/v1.0/kicad/UNO_HGA22_V1.kicad_pcb and its schematic hardware/v1.0/kicad/UNO_HGA22_V1.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Its repository publishes it under the MIT licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).