I'm looking for a copy of the article "An Arduino-based receiver noise figure alignment aid" from RadCom July 2015, Vol. 91, No. 7 written by Barry Chambers, G8AGN. In the article Barry explains a "nanowave optimisation device" that also has applications in RF.

The article should include an explanation of his "photon tube" which is intended for testing optical receiver sensitivity. The purpose of the "photon tube" is to allow comparison of different optical sensors and to test the sensitivity of various detector designs. 

The original discussion and information about Barry's work was on the old UKNanowaves forum on Yahoo.com, well before the forum was moved to Groups.io. The info could be helpful for Rob and others playing with optical comms. 

73, Doug Reed, N0NAS. 

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