Although i have not done much noise/emissions testing on this topic, have we considered recommending turning off HDMI to reduce emissions from the Pi, when people are considering mounting the Pi, LNA and SDR on the mast?
i.e. 891,000 MHz and others
Although by disabling HDMI it may make it harder to diagnose if issues occur, it may also reduce power consumption for stable remote nodes. I keep a spare SD Card available with HDMI activated for any occasions where SSH doesn’t work.
Issue this command from a SSH session.
Powering off HDMI
This may need to be made permanent, as I expect HDMI reactivates after reboot.
To power back on.
Powering on HDMI with preferred settings
In some circumstances you may need to also issue the following for the screen to display properly.
fbset -depth 8; fbset -depth 16