On 22nd Feb 2026 Clive and myself performed another test over our 17km path home to home.
Once again the 4x Photodiode Rx with it’s small lenses was the receiver.
A ‘Good’ signal was received over an hour or so test. ‘Good’ meaning about 10dB s/n in 4mHz bandwidth!
It was noted that the receiver requires some 20-30deg elevation for good operation, possibly to be able to ‘see’ more sky due to obstruction by local trees and buildings.
There was fading probably due to varying cloud cover.
NOTE – Beacon is precisely on 2010Hz, the following plots were using a different soundcard at Clive’s end, the Behringer 404, it has a few Hz clock error!!
The next step has been decided and we will be installing a permanent receiver at Clive’s location, it will use a raspberry pi with gps receiver and sound device to data log the optical signal from the receive head.
This will enable us to monitor the carrier s/n and also to perform automated EbNaut tests.
I will add a page on my website with the live data from the receiver very similar to the one I have done for my VLF receiver.
Here’s a screenshot from a test the day before on 21st Feb, it shows much stronger signal but also some connection issues that were due to a loose bnc socket on the receive head, now resolved.
