Introducing Leshy2 — an ESP32-C5 field tool inspired by ESP32-DIV, and a hello about collaboration

[anton-vinogradov]

Hi cifertech and the ESP32-DIV community

First, a big thank you. ESP32-DIV is a wonderful project, and it is the reason I started building. I learned a lot from your work, and my firmware began as a fork of ESP32-DIV (MIT). All credit for the foundation goes to you and this community.

I want to introduce a project called Leshy2 and, more importantly, ask if you would be open to working together in some way. Repo (MIT, design stage, WIP): https://github.com/anton-vinogradov/esp32-leshy2

Why I started

I love ESP32-DIV, but DIV v2 has no 5 GHz WiFi. The new ESP32-C5 changes what is possible: it is a single RISC-V MCU with native WiFi 2.4 + 5 GHz and BLE. That one chip removes the main gap, so I began porting the firmware from ESP32-S3 to C5 and grew the hardware around it.

Leshy2 is meant to stay in the same spirit as DIV: an open, portable, multiband RF field tool. It is not a replacement — it is a next step I would love to build with the community, not apart from it.

What Leshy2 adds beyond DIV

• ESP32-C5 single chip: native 2.4 + 5 GHz WiFi (5 GHz is Marauder-class: scan, deauth, beacon/probe flood, sniff management frames)
• Si4732 receiver: CB 27 MHz + full HF/shortwave + MW/LW (AM/SSB/CW) + FM broadcast, with real analog audio out
• SA868-U UHF voice: NBFM walkie RX and TX (region/licence limited)
• LoRa SX1262 / Meshtastic for encrypted text at kilometer range
• M5-compatible expansion: a faithful Cardputer-ADV EXT 14P cap slot (hosts the LoRa + GPS cap) plus 2x Grove ports (NFC, RTC, IMU/compass, more)
• 2S 18650 power (~7.4 V, ~18 Wh) with a proper PMIC and USB-C PD, so it runs while charging

Onboard RF is all self-built on shielded u.FL modules (3x nRF24L01+PA/LNA, CC1101, plus the above), direct SPI-TFT for a fast waterfall, microSD, IR TX/RX, WS2812 + buzzer, encoder. Target BOM is around 115-150 USD.

Honest limits (so there is no hype)

• 5 GHz is Marauder-class only — no WPA handshake capture, no injection, not a WiFi Pineapple. That needs Linux, which I skip on purpose to keep battery life.
• It is not a HackRF — no continuous 1 MHz-6 GHz with arbitrary TX.
• 27 MHz and the HF/FM side are receive only. No wideband jamming (that is illegal under US Communications Act 333 and EU RED).

The ask

Would you and the community be open to collaborating? I am flexible on the form, for example:

• Sharing design ideas and schematics openly (KiCad, 4-layer)
• Cross-pollinating firmware between DIV and the C5 port
• Or, if it fits your roadmap, helping DIV itself move toward some of these features (5 GHz, HF listening, expansion)

I do not want to pull attention away from DIV or push my project. I just think these ideas could help both, and I would rather build in the open with people I learned from.

Leshy2 is MIT, same as ESP32-DIV, and it credits DIV clearly. Architecture is locked and the next step is the KiCad schematic, so this is a good moment to align if there is interest.

Thank you again for ESP32-DIV and for reading. Whatever form (or none) feels right to you, I am grateful for the project and the community around it.

— Anton

[cifertech]

@anton-vinogradov thanks for the kind words and for sharing Leshy2, really impressive scope.

I'm intrigued by the ESP32-C5, especially since it supports native 5GHz. I've also been considering the Si4732 for another project, so that part really caught my attention. I'm open to sharing ideas, particularly regarding the firmware, since the feature modules are modular enough to allow for easy porting. Let's continue this conversation! I look forward to seeing the KiCad schematics when they're ready.

[anton-vinogradov]

Phase 1 update — Leshy2 (schematic design done)

Small update for anyone following. The design phase is finished, and the whole thing is public (MIT, EN+RU): github.com/anton-vinogradov/esp32-leshy2

The main decision: Leshy2 is now TWO chips, not one. An ESP32-S3 stays the brain (UI, display, every wired radio, SD, buses, 2.4 GHz Wi-Fi + BLE), and an ESP32-C5 is added only as a co-processor for the one thing the S3 can't do — native 5 GHz Wi-Fi (plus 2.4 / BLE / 802.15.4). Keeping the mature S3 base and bolting on the C5 turned out cleaner than trying to run everything on a single C5.

What is done: the architecture is locked and the full schematic is written sheet by sheet as transcribe-ready docs (power, MCU + buses, RF, audio, expansion, indicators) — exact parts, net-by-net connections, and the GPIO/PCA9555/74HC138 pin budget. All RF is self-built on shielded modules: 3x nRF24L01+PA/LNA, a bare CC1101 (315/433/868/915 via an SP4T), SX1262/LoRa, Si4732 (HF/CB/FM RX), SA868-U (433/446 voice). Nine antennas, 2S 18650 power.

Honest scope: 5 GHz is recon-class (scan / sniff / beacon-probe flood); deauth is a PoC question we will answer on a bare C5 devkit before ordering any board. It is not a HackRF (no wideband capture / arbitrary TX), and no jamming — ever.

Next: capturing the sheets in KiCad, then the 4-layer PCB.

Review is very welcome, especially from DIV folks — extra eyes on the nets, power, RF layout, and pin choices would help a lot. This builds on ESP32-DIV and we want to keep the two friendly and feed useful bits back. Thanks, cifertech, for the original.

[anton-vinogradov]

Phase 2 — schematic complete on real parts (KiCad-ready)

Thanks @cifertech for the earlier note — you said to ping you once the KiCad schematics were ready, so here we are 🙂

Since the Phase 1 update the whole schematic isn't just drawn but realized with real parts and merged into one board:

• Captured as code. All six sheets (power · MCU+buses · RF · audio · expansion · indicators) are written as tscircuit — one source generates the schematic, the netlist and a KiCad PCB, so nothing is hand-drawn. They merge into a single board.tsx.
• Real parts, not ideal symbols. Every IC/module carries its manufacturer-verified footprint + pinout, pulled by LCSC part number, and the whole thing exports clean to KiCad.
• Two adversarial design-review passes before spending a cent on a PCB. Going to real parts and reviewing hard caught ~14 real defects, 4 of them board-killers — e.g. the 2S charger wired for the wrong topology; two S3 GPIOs that simply aren't bonded out on the WROOM-1U module (those control lines moved to an I²C expander); a reversed I²C ESD array; a single-supply walkie mis-modeled as dual-supply. All fixed.
• Result: one board, 174 real components, connectivity proven (KiCad schematic_parity = 0), ready to lay out.

All MIT and open — schematic-as-code + the merged board.kicad_pcb are in hardware/tscircuit/; the bilingual per-sheet design docs are under hardware/.

Next: PCB placement + routing in KiCad (RF feeds / ground / antenna keep-outs by hand) → gerbers. No hardware built yet — still all on paper.

And yes, I'd love to take you up on the firmware offer. Leshy2's software ports from my ESP32-S3 leshy fork of DIV, so there's a lot of common ground on the S3 side — happy to compare notes on the C5 co-processor and Si4732 whenever it's useful. 🙏