Smol Receiver
Table Of Contents
- 📶 Receiver Options (Ranked by Signal Strength)
- 📡 USB Dongles
- 📡 Microcontrollers Modified Into USB Dongles
📶 Receiver Options (Ranked by Signal Strength)
To ensure optimal signal integrity and range, it is essential to use boards equipped with high-quality antennas. Boards featuring a PCB antenna or external antenna are generally the most effective option for use as receivers.
Nordic Semiconductor nRF52840 Dongle, Seeed Studio XIAO nRF52840 are not included due to lack of data.
| Receiver | Tier | Typical Price (USD) | Notes / Best For |
|---|---|---|---|
| 🟢 HolyIOT-21017 | Superior | ~8-18 USD |
Highest performance for the highest price.
Includes an RFX2401C FEM amplifier — reported to provide significantly increased signal strength. |
| 🟠 ProMicro nRF52840 with Wi‑Fi Antenna Mod | Affordable | ~7 USD | Recommended go‑to option; best price‑to‑performance when modified with a Wi‑Fi antenna. |
| 🟠 ProMicro nRF52840 with Wire Antenna Mod | Affordable | ~6 USD | Simple 31.2 mm wire monopole antenna; low cost and easy to build; modest range improvement. |
| 🟠 eByte Dongle (E104-BT5040U) | Limited | ~6,25 USD for min pack of 2 on Alibaba | Cheapest PCB‑antenna dongle. Signal tends to degrade beyond ~3 m, especially when obstructed by body parts. |
| 🚫 ProMicro nRF52840 (Unmodified) | Avoid | ~2-4 USD | Unmodified board; Same as trackers. Not recommended, as antenna mods are better. |
📡 USB Dongles
These dongles are equipped with relatively well-optimized PCB antennas. For improved signal integrity, especially in constrained environments, consider using a USB extension cable.
| Dongle | Description | Links |
|---|---|---|
| 🟠 eByte Dongle (E104-BT5040U) |
Cheapest option with a PCB antenna. - E104-BT5040U is the correct model to use. It is fully compatible with the Nordic Semiconductor nRF52840 Dongle. - E104-BT5040UA is not compatible. It is only capable of capturing BLE4.2 and BLE5.0 protocol packets. |
|
| Nordic Semiconductor nRF52840 Dongle (PCA10059) | Official Nordic development hardware. | |
| 🟢 HolyIOT-21017 aka HOLYIOT-21017-nRF52840 | Has a FEM (Front End Module), specifically an RFX2401C radio booster. Currently regarded as the highest-performance option. |
📡 Microcontrollers Modified Into USB Dongles
🚫 Option 1: Unmodified Board
Consist of ProMicro nRF52840 or Seeed Studio XIAO nRF52840.
🟠 Option 2: Wire Antenna Mod
Consist of a ProMicro nRF52840 or Seeed Studio XIAO nRF52840 attached with a 31.2 mm wire to the antenna pin to form a basic monopole antenna.
Refer to Smol Schematics -> Antenna (extra option) for the solder point location.
Wire Options
- Solid core or stranded copper wire (e.g., 23-26 AWG).
- Wire salvaged from an Ethernet cable.
🟠 Option 3: Wi-Fi Antenna Mod
Consist of a ProMicro nRF52840 or Seeed Studio XIAO nRF52840 attached with a Wi-Fi antenna.
Recommended due to a good balance between build difficulty, performance, and cost.
Example receiver from LyallUlric's Stacked SmolSlime build, equipped with an OOTDTY 2.4G/5.8G Dual Band Antenna.
Refer to Smol Schematics -> Antenna (extra option) for the area to remove and solder the IPEX or SMA connector.
Community-Tested Antennas
Community Recommendation
| Image | Listing | Link |
|---|---|---|
|
OOTDTY 5 Pcs 2.4G/5.8G Dual Band Antenna 8DBI High Gain Internal PCB Aerial for WiFi Router WiFi Antenna |
IPX–SMA Conversion Setup
| Image | Listing | Notes | Variant | Link |
|---|---|---|---|---|
|
2PCS Mini Rubber 3dBi 2.4ghz WIFI Antenna SMA Male Router Bluetooth Antennas Wireless Module 2.4g Antena External Aerial | Best tested performance (based on Lyall’s tests) | Color: B | |
|
IPX to SMA RF Coax Adapter Assembly Pigtail Cable,SMA Connector Cable Female to UFL |
Any IPEX or SMA cable should do.
Cut cable at marked location on the image. |
Shorter cables preferred. |