I am planning to do the internal RF loopback in the LMS6002D chip. I want to use the transmitter to calibrate receiver, and vice versa. So far I’m trying to loop TX to LNA2 without success. I cannot see any signal out of ADC although on TX is programmed for 3.84 MHz CW. I’m using the FPGA to send SOPI commands. Any ideas what where might be the issue?
In the programming guide it says to power down the LNA. Which register is doing that?
Hello,
I have exactly the same issue. I cannot see the RF loopback working.
This is the list of register dump from LMS6002D chip.
Can you help me with this problem?
Best Regards
I’m also having the same problem. I can loop back externally via SMA connectors, but for the life of me I can’t get internal RF loopback to work. What’s the magical setting for the LMS6002?
I’m still not able to do an internal RF loopback. I’m using the EVB6002-6 board and the supplied GUI so maybe this forum isn’t the best place to discuss this. I was thinking it was a register setting issue inside the LMS6002D chip. Maybe it’s a GUI/EVB problem.
I don’t think there should be a problem with EVB or GUI. Can you control the chip at all? You can perform the register test to see if everything is OK.
The Lime supplied GUI is the same as GUI for DE0-Nano project or FFTviewer. To enable RF loopback follow the steps below:
Set TxPLL and RxPLL frequency to have 1 MHz difference in between.
Set TX VGA1 gain to -10dB and TX VGA2 to 25dB, in “Tx RF” tab.
Select Active LNA in “System” tab. For example LNA2.
Select RF Loopback option in “Top Level” tab. Find “RF Loopback Control” window and select “TxMIX to LNA2 Path”.
I think, now you should be able to get RF loopback working.