Just feedback to let you know…
FSK is supported since the in june 2023 released OpenMQTTGateway v1.6.0! (Thanks @NorthernMan54 and @1technophile)
I was able to receive data from my weatherstation (Bresser 5in1) with a LILYGO LoRa32 V2.1 v1.6.1 868 version. I would presume this will also work on a Heltec
Here are OpenMQTTGateway settings:
[env:lilygo-rtl_433_fsk]
platform = ${com.esp32_platform}
board = ttgo-lora32-v21
; ~/.platformio/packages/framework-arduinoespressif32/variants/.../pins_arduino.h
board_build.partitions = min_spiffs.csv
lib_deps =
${com-esp32.lib_deps}
${libraries.ssd1306}
${libraries.rtl_433_ESP}
build_flags =
${com-esp32.build_flags}
; *** OpenMQTTGateway Config ***
;'-UZmqttDiscovery' ; disables MQTT Discovery
'-DvalueAsATopic=true' ; MQTT topic includes model and device
'-DGateway_Name="OMG_lilygo_rtl_433_ESP"'
; *** OpenMQTTGateway Modules ***
'-DZgatewayRTL_433="rtl_433"'
'-DZradioSX127x="SX127x"'
; *** radio settings ***
'-DOOK_MODULATION=false'
'-DCC1101_FREQUENCY=868.30'
; *** ssd1306 Display Options ***
'-DZdisplaySSD1306="LilyGo_SSD1306"'
; '-DLOG_TO_OLED=true' ; Enable log to OLED
; '-DJSON_TO_OLED=true'
; '-DLOG_LEVEL_OLED=LOG_LEVEL_NOTICE'
; '-DDISPLAY_IDLE_LOGO=false'
; '-DDISPLAY_BRIGHTNESS=80'
; '-DDISPLAY_METRIC=false'
custom_description = For ESP32, Gateway using RTL_433_ESP and RadioLib in FSK mode
custom_hardware = ESP32 LILYGO LoRa32 V2.1