Re: RFI from uBitx TX after AGC and other mods installed

Don, ND6T
 

Do not place that capacitor from Q1 base to emitter. That will make a dandy blocking oscillator. Pin 7 of U1 already has a bypass (C78). It's just not shown on the schematic. Rather try hanging a big electrolytic across 5 volts to ground. Something like 100 uF, or 1,000 uF. in addition to a 10 nF (.01 uF). I haven't had to use any filtering on 5 volts other than the 1uF which is already on the Raduino. But my uBITX has a 1000 uF. on the 12 volt lead to the big board and the Raduino. I'm pretty sure that's why I have no issues. -Don

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