I've been successfully using these: https://www.aliexpress.com/item/Wireless-technology-popularization-Si4432-wireless-transceiver-module-wireless-module-cylindrical-antenna/32475405156.html for a while: I am using a 5V Arduino (actually I am using a ProMini, a UNO R3 and something m128 based that I put together myself), a separate 3v3 buck-converter and a CD4050BE to perform the 5V to 3v3 level shifting of all the signals going to the transceiver. My respective circuits works nicely with this transceiver - using RadioHead RH22.)
I had decided to use the above radio for its ease of use/replacement (i.e. no soldering of 1.27'' stuff required).
When one of my respective transceivers recently died, I ordered this one here as a replacement: https://www.aliexpress.com/item/si4432-data-transmission-module-Wireless-module/32668654149.html
It looks very similar, is based on the same SI4432 and the specs for its 2.54'' pin headers are exactly the same as the ones for my "old" transceiver. But when looking closely at the PCB, there are small differences with regard to the used SMD components and their respective layout on the PCB. (According to the seller it is an "updated" version of the thing that I had been using originally.)
Unfortunately my original circuit no longer "works" when I am using just one of the "new" transceivers. (i.e. the RH22 lib on the device does not report any problems but the device with the "new" transceiver no longer seems to communicate with any of the devices that still use the "old" transceivers.)
When I replace the transceivers (no change of the software) on both ends with one of the "new" then communication works again (eventhough I have the impression that it in less reliable than with the "old" transceivers..)
Any idea why the old/new transceivers might not be compatible (mb some default setting that is not explicitly reset by the RH22 lib?)?