T-BEAM-APX2101-V1.2 NO RX

[EA1RJ]

Hello, i´m trying to configure rdz_ttgo_sonde on Lilygo T-Beam V1.2, i´m uploading main0.98-C3-full.bin using flash_download_tool. i have try selecting diferents ESP32 chips, the boards has an ESP32-D0WDQ6(v3) and when i select ESP32-D2WD it works, in main window some times autodetect ttgo T-beam (V0.7) and some times (V1.0).

It works fine but no RX, the board has a label that sais 432/470 Mhz so i think that the rx is SX1278 but not sure, shoud i desolder shield to check? borad has AXP2101.

i have read: Lilygo T-Beam v1.2 (with AXP2101): There are two 433 MHz variants, one with SX1278 and one with SX1268. Only the first variant will work.

Any help?

Thanks in advance

EA1RJ - Ricardo

[dl9rdz]

Usually the SX126x chips have a different label on the outside, so if it just says 433/470 and NOT SX1276 then it should be the right board. (I did have one case where a board had a 433/470 label on it but inside was the 900 MHz variant of the chip.... bit this is a very rare case).

As long as the board works the autodetect is not that important. If it shows the battery voltage (on web Interface or on the right screen on the TTGO display) then the AXP chip is configured correctly.

[EA1RJ]

Thanks for quick response, i have been using this board as a 432 tracker (CA2CXU firmwarwe) so i´m sure it works fine on 432.

i have one TTGO LORA v2.1_1.6 running rdz sonde and i have tried receiving a sonde with 100 dBm to disconect it and conect Lilygo T-Beam v1.2 and don´t receive nothing.

I´ll try to adjust RX parameters and i´ll tell you

[dl9rdz]

Ah ok this was a rather weak signal.

There are some quality variations in terms of sensitivity between boards (both between types of board and between individual boards). The TTGO LoRa v2.1_1.6 in my experience is the best board. But usually the T-Beam usually is not particularly bad either, in particular any version >= 1.0 (the PMU in the old 0.7 can be a bit noisy).

If you have connected a larger TFT display this can affect sensitivity due to noise from the SPI bus to the display (depending on length and placement of wires and proximity to the antenna).

Also for weak signals the frequency calibration can help a bit.

[YT9TT]

Hello EA1RJ and DL9RDZ,
I am having the same issue.
I had T-Beam T22_V1.1 with AXP192 chip and it worked flawlessly. I recently bought from lilygo a new T-Beam board labeled TBeam-AXP2101-V1.2 (with 20230508 date on silk)

I have two of them, one with, one without LCD.
They are pretty much deaf; I tried firmware all from master_v0.9.5-B17-full to main0.98-C3-full

I tried some debugging and did a few things:
First, I put 2 "deaf" T-Beam's and two TTGO LORA v2.1_1.6 labeled T3_V1.6.1, one with latest 0.98 and one with Mysondy go firmware.
They were on the same table, outside, with tuned antennas (checked with NanoVNA) and for the first test I swapped antennas between them. T-beams had no RX at all while those LORA T3 worked OK.

Second, I took an external antenna and connected to T-Beams and got somewhat reception but much more Errors than OK decoding, signal varied from -70~-110

Third, I installed Mysondy go onto one "deaf" T-Beam, and it worked right away. As long M10 sonde was in range, T-Beam with Mysondy go worked OK, although Lora boards were much more sensitive. Other T-Beam, with the latest 0.98 firmware, didn’t decode at all as time passed by.

I noticed when powered on, autodetect info on the web homepage shows 150 (unknown board) then when I press reset button, it shows correct board 151 and on serial console both times I get info (Sonde.cpp: Board fingerprint is 22 Sonde.cpp: Autoconfig: looks like T-Beam 1.0 or M5Stack Core2 board)

What else can I do to try solving RX issue?

Mickey YT9TT