Just did some experimentation with the meshcore radios this morning. I had to go back here in the group and edit a post I made that said to avoid the Heltec T096.

I have found that the FEM (front end module) on the Heltec T096 is finicky. It seems to either cause increased RX noise or outright mutes the receiver. You can issue the command SET RADIO.FEM.RXGAIN OFF to disable it.

example... with FEM RXgain ON, the noise floor was showing at -100db (unusually noisy.). I switched the FEM RXgain off and noise floor improved to -116db. You may recall that eariler this week I noted a 16db difference in link margin... I think I found it. At another point this morning, I switched FEM RXGain ON and the noise floor went to -120db which indicates a dead (muted) receiver. So the FEM module is flakey.

Actually the heltec with the FEM disabled seems to have a 4db receiver advantage over the RAK 4631.

Transmit test
RAK -> St Chs  6.5db
T096-> St Che  3.75db
RAK ->Oswego  10.5db
T096->Oswego   3.75db

Receive Test
St Chs->RAK  1.5db
St Cos->T096 3.5db
Oswego->RAK  9.0db
Oswego->T096 9.75db