Well I went cheap cheap cheap with this. It is made our of bottle caps and old transistor radios. https://www.ebay.com/itm/Dual-2-Port-US ... SwV4BZxj-H

Just got done flight testing it. Works just fine. No static

Tim

I'm going to try these out. They make a panel output and an in-line version. I've done some bench testing and they seem to work well. I'll let you know if I have any noise issues. They are not FAA approved in any way. A careful reading of the CAR3 regs on adding electrical items may or may not be helpful for people with older planes. (carefully worded to avoid starting a tedious dueling regs debate).

https://www.amazon.com/gp/product/B06XR ... UTF8&psc=1
https://www.amazon.com/gp/product/B01N4 ... UTF8&psc=1