Hi all. I’m new here. I’m a Kiteboarder but only foiled behind a Jetski trying to learn the foil. 7Larky came up at a good price for a person like me with my set of skills.
I got a new to me 7Larky SL04. Couldn’t get the unit to pair with either of the controller so knew I had my work cut out. I dug out the receiver by following the antenna line and pulling of bits of potting one bit at a time. I free enough wire from the ESC to receiver to pop it out.
I took the time to plug a servo tester into the ESC and it worked fine. It’s a Hobbywing XRotor Pro Series 80A HV ESC.
When the receiver powers up and looks for a pair it flashes 2 red LED’s and that’s it. The PCB is the same as pictured on the manual. Not much markings one it.
It has a generic NRF24 module on it with a Hirose U.FL. I think I have one in a part’s box here. I’ll swap that over first.
I’ll get back with my progress.
[edit] module is a AS01-SPIPX. Basically a NRF24 wtih a 20dBm RF amplifier.
I don’t think this repair will go as planned. What I have learned…
I wired up another NRF to the receiver. The RX has 2 LEDs. One LED is on if the NRF is not communicating, probably a critical error LED and the other LED seems to be link status. One of the 3 working TX unit’s I have lights up the link LED and remains lit only while the TX is on, so there is some communication, but does not display any telemetry on the screen. Receiver signal indication remains no signal. It’s like the RX is stuck in the handshake and can’t get past it. Also it still will not pair.
The RX has a switch pads on the PCB. I wired a switch onto that to try to see if it would reset/ rebind etc. No change there.
I pulled a not working TX apart. Removed the faulty regulator that was shorting the power rails. Thermal camera diagnosed that in seconds. I then hooked up a FTDI to the Uart0 on the 15W4K48S4 MCU. No luck there and the STC15 series has no flash read function in the bootloader so I wont be pulling the FW off one of these without serious tools I don’t have (decapping).
What next.. I’ll pull the NRF of the disassemble TX unit and fit it on the RX. I doubt it will work but worth the 5 minutes to test.
I’m exploring TX/RX options now. Either a Maytech V3 or a BreRemote. BreRemote has my interest the most since it is open source and a better radio link.
