Re: 12v->5v noise
A Raspberry PI 4B can only accept 3 amps on it’s USB-C connector. It does desire 5.1V though, not 5V.toggle quoted messageShow quoted text
It’s tricky finding a 5.1V USB source that isn’t 110VAC powered.
I have been using a switcher supply made by DROKing in the far east.
This is a $15 or so device which has a multi-turn pot to set the output voltage and accepts a wide range of DC voltage on the input.
A key feature is that when main power is turned on, the unit immediately outputs the desired voltage to the USB connector. Some of the variable output USB converter items power on with the USB output disabled.
The bug with this particular unit is that it appears that DROKing has discontinued it in favor of a menu driven device (at the same price) but which powers on with the USB output disabled. However, the unit continues to be available in various places including Amazon. However, for a while the ISBN number kept changing and so any link to the offering seemed temporary. That sounds like somebody is cloning the device and it isn’t DROKing anymore. Dunno. Maybe DROKing changed their minds when the Internet blew up after they discontinued it?
I haven’t had any particular noise on HF from this, though I live in a suburb and have plenty of noise already. YMMV.
Tadd / KA2DEW
Raleigh NC FM05pv
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