Choosing hardware for 433 MHz: SX127x vs SX126x vs CC1101 vs RXB6 vs RTL-SDR (pros and cons)

[ZerOne]

A comparison of the common ways to get 433 MHz remotes and sensors into a smart home. It follows on from whether a LoRa chip can receive 433 MHz OOK/FSK. The facts come from datasheets, vendor pages and project docs as at October 2026. The pros and cons are my reading of those sources plus a few opinions, which I flag. I have not benchmarked these side by side, so I give no range numbers.

SX127x board (SX1276/78) plus ESP32

• Pros: LoRa and 433 MHz OOK/FSK on one chip. 433 MHz boards such as the LILYGO LoRa32 V2.1 433 and Heltec WiFi LoRa 32 V2 433 are the ones the rtl_433_ESP author used. Receive bandwidth is programmable (ESPHome lists 2.6 to 250 kHz), so it can be tuned to different devices. It can transmit OOK too. Supported by rtl_433_ESP, OpenMQTTGateway, ESPHome and RadioLib (OOK, direct mode).
• Cons: one demodulator at a time, so OOK or FSK, not both, and not LoRa at the same moment. The rtl_433_ESP author reports it is less sensitive than an RTL-SDR, with half the range or less. You may need to tune the OOK threshold. rtl_433_ESP's README lists 223 OOK and 153 FSK decoders, which is a subset of what rtl_433 itself offers.

SX126x / LLCC68 board

• Pros: excellent for LoRa and LoRaWAN, and common on new boards.
• Cons: no OOK, so it is the wrong chip for generic 433 MHz remotes. See the first thread for the sources.

CC1101

• Pros: a general sub-GHz radio. The TI datasheet lists 2-FSK, 4-FSK, GFSK, MSK, OOK and ASK, bands of 300 to 348, 387 to 464 and 779 to 928 MHz, and an asynchronous serial mode for compatibility with existing designs. Supported by rtl_433_ESP, OpenMQTTGateway (including its RCSwitch/Pilight gateways) and an ESPHome component. It transmits as well.
• Cons: no LoRa. Module quality varies between sellers. In my opinion it is the safer buy if 433 MHz is all you want, but I have not compared sensitivity.

RXB6 and similar superheterodyne OOK receivers

• Pros: very simple. 3 to 5.5 V, a DATA pin, about 6 mA, and a wire antenna of about 17 cm. A seller page lists -116 dBm and about 6 mA at 3.3 V, while the manufacturer's datasheet text I read said about -110 dBm. Listings vary, so treat sensitivity as a claim. Good for EV1527/PT2262-style remotes and sensors with RCSwitch, pilight, ESPHome remote_receiver or OpenMQTTGateway's RF module.
• Cons: fixed at 433.92 MHz, ASK/OOK only (no FSK) and roughly 10 kbps at most. It is receive only, you get no spectrum view, and an RSSI pin exists only on some versions.

RTL-SDR dongle plus rtl_433

• Pros: a wideband receiver that handles OOK and FSK, with the biggest set of decoders. rtl_433 describes itself as a generic data receiver for the 433.92, 868, 315, 345 and 915 MHz ISM bands. Best for working out what an unknown device sends. See thread 117 for an MQTT and Home Assistant setup.
• Cons: it needs a host computer such as a Raspberry Pi, and receives only.

Other options in one line each

• Sonoff RF Bridge running Tasmota: a ready-made OOK bridge, see the Tasmota docs. It is not a LoRa chip, so I only mention it for comparison.
• pilight: its manual says it works with 315, 433 and 868 MHz devices, but only 433.92 MHz is currently supported. It reads pulses from a receiver on a GPIO pin. I found no documentation of it using an SX127x directly.
• The newer LR2021 chip lists OOK, but I would not build on it for this yet. See the first thread.

My rough picks (opinion)

• Don't know what your device sends? Start with an RTL-SDR and rtl_433.
• Only EV1527-style door, PIR and remote devices? An RXB6 or any of the radios above will do.
• Already own a 433 MHz SX127x board? Use it. Check the chip first, as many newer boards have SX126x.
• Want OOK and FSK sensors on an ESP32 with MQTT? An SX127x or CC1101 with rtl_433_ESP or OpenMQTTGateway. There is a walk-through in the ESP32 project thread in this forum.

Question for the group: which receiver are you using for 433 MHz at home, and how does its range compare with the original remote's range?