Use VHF with 2 NUCLEO-WL55JC1

[Ted_]

Hello,

I bought 2 NUCLEO-WL55JC1 to send and receive some data.

I used example code in Lora which work very well (SubGHz_Phy_PingPong).

My problem is to use VHF (156.8750Hz).

I modify the code (RF_FREQUENCY, FSK_FDEV, FSK_DATARATE, FSK_BANDWIDTH, USE_MODEM_LORA = 0 and USE_MODEM_FSK = 1).

I change my antenna for a DELTA12/x/SMAM/S/S/17 for my 2 nucleo.

The 2 boards still communicate.

Now, I also have to change the hardware according to the Application note AN5457.

Unfortunately, there is no information to change my hardware (only for L6 (160 nH) but nothing for the equivalent circuit). Anyone knows which value I can attribuate for each component of the network (figure 26) in order to optimize the consumtion and the power of my 2 boards?

Thank you,

[STTwo-32 · Accepted solution]

Hello @Ted_  and welcome to the ST Community.

as I understand you are looking for the values you should attribute to each component in the figure 26 of the AN5457. I suggest you use the formulas mentioned in the section 5 of the AN5457 to calculate the values you are looking for. If you can't find the impedance value for your application, you can contact the ST local sales office.

Best Regards.

STTwo-32

[Ted_]

Hi @STTwo-32, thank you for your feedback.

Indeed, I don't have the impedence value, it is my problem.

Therefore, I found the datasheet of the STDES-WL5U4SHW which use 169MHz for the VHF.

Do you think it is ok to use this document for my development for 156MHz or I definitively have to contact the ST local sales office?

Thank you.

[STTwo-32]

Hello again,

You should contact your ST local sales office to have credible data for your application.

best regards.

STTwo-32

[Ted_]

Ok, i'll do that, thank you again.

Ted