Good evening all,
I put together a DIY ORx with a Raspberry Pi 3, the Outernet USB receiver, Outernet patch antenna, and Outernet LNA / filter.
It worked really nicely for a couple of days - SNR in the 4’s and 5’s (signal state 4) and got lots of cool downloads. (Future Outernet Engineer picture, rocket stove plans, solar distiller plans, weather pictures, etc…) For the past few days, my setup struggles to get above an SNR of 1.0 and it rarely has a signal state greater than 1. The setup is unchanged, so I suspect something is not working right. It’s pointed properly both in azimuth and elevation.
I tested the patch antenna and LNA/filter by disconnecting the RPi and USB receiver. To the output of the LNA/filter, I hooked up an Airspy receiver with the bias voltage turned on. I can clearly see the Inmarsat signal at 1539.875 MHz and the SDRSharp program calculates an SNR of about 9. Using this setup, I confirmed that the pointing is good, and really, the patch antenna isn’t as sensitive as I thought it would be to errant pointing. I don’t know if this confirms that the LNA/filter is working properly or not.
Is it possible that there is an issue with the USB stick receiver? Has there been issues with the satellite, maybe? My next step is to buy another USB receiver and LNA/filter to see if they improve things.
Any hints greatly appreciated. I’m in the southern USA and am a ham radio operator / amateur electrical engineer.