This video is very interesting indeed. A fellow built of high sensitivity, High amplification RF and audio probe. Put a little B plus on your B+ bus, go around capacitors and resistors and this thing is sensitive enough to pick up the miniature lightning inside a leaky cap even when it's too small to be heard in your speaker&nbsp; Pretty cool. I intend to build one, although I probably will try to use IC amplifiers after a Hi-Z fet front end, rather than discrete comonents but we'll see. Has a schematic in the video and more information under the video.&nbsp; I'd like to try it with B+ on the bus but the filaments turned off. You should still get the lightning.<br><br><span style="font-size: 14px;">https://youtu.be/uiK1BD7HILo<br></span><br>73 Dave AB5S<br><br><br>Sent using myEarthLink<br><br>