An experienced VHF Radio/Radar/Sonar maintenance provider commented that my 15-year old Standard Horizon VHF Radio has not lost its sensitivity, although he affirms that in the last 15-20 years or so, the EMI radiated/conducted has grown phenomenally with the proliferation of hand-held computers (cellphones, iPads etc); however, he did manage to ameliorate the sensitivity of my VHF Radio by substituting the front-end mixer transistor with a current low-noise one.

An avid Radio Ham since his youth, he say the HF band is so noisy that he doesnīt have the patience anymore to listen in !

So poster # 33 may add this enhanced EMI factor in when a customer complains of poor performance in the field, while of course certification in the lab measures the compliance of elecrical/electronic equipment against a set of mutually agreed upon standard (s).

I also wonder sometimes if LED lighting around a boat - recall that a LED is a light-emitting junction diode - being stimulated with extraneous electromagnetic radiation (radar, VHF etc) isnīt itself generating intermodulation/distortion products that are irradiated and/or conducted in the wiring installation ??