[Elecraft] Powering KX3 from Bioenno charger with battery in between

[Jim Brown]

On 10/19/2021 1:16 PM, Julia Tuttle wrote:
> Am I missing anything here?

Yes. Most chargers are noisy, because they contain switch-mode power 
supplies and regulators. One charger I got from them was noisy. When I 
talked to them about it, they sent me a linear charger with simple 
hysteresis controller, and it was quiet.

The first thing to do with ANYTHING that plugs into the wall is to check 
it for RF noise, using a portable RX like one of those described here. 
My favorite is my vintage Kenwood TH-F6A talkie, which has widerange 
coverage. Below 10 MHz, it defaults to a loopstick in the base, and with 
a software switch to use the SMA connector. I probe with the loopstick 
around 2 MHz. One of the Tecsun radios works well too. Check the unit 
itself, and any wires connected to it, including the AC line, DC power, 
and any signal cables.

http://k9yc.com/KillingReceiveNoise.pdf
http://k9yc.com/KillingRXNoiseVisalia.pdf

73, Jim K9YC