Muvideo : did you build it dead bug style on some copper board?
I've looked around the web, but they all seem a bit lacking. There is one which uses an opamp at the input, but that's just adding way way more input capacitance than necessary. The poor man's 1 GHz active probe is AC coupled and will be highly non-linear because of the small source resistor. The ancient one from Troubleshooting Analog Circuits still seems the best one over all. I can find no schematic at all for one with active DC offset correction, although that's a bit of luxury I could forego.
Anyone know of a better circuit? (Preferably with PCB layout.) I found these :
http://books.google.nl/books?id=3kY4-HYLqh0C&lpg=PP1&pg=PA16#v=onepage&q&f=false
http://elektrotanya.com/files/forum/2009/10/e04a036.pdf
http://welecw2000a.sourceforge.net/docs/Hardware/Aktiver_Tastkopf_mit_OPA659.pdf
http://oliverbetz.de/hit/hit_e.htm
I've looked around the web, but they all seem a bit lacking. There is one which uses an opamp at the input, but that's just adding way way more input capacitance than necessary. The poor man's 1 GHz active probe is AC coupled and will be highly non-linear because of the small source resistor. The ancient one from Troubleshooting Analog Circuits still seems the best one over all. I can find no schematic at all for one with active DC offset correction, although that's a bit of luxury I could forego.
Anyone know of a better circuit? (Preferably with PCB layout.) I found these :
http://books.google.nl/books?id=3kY4-HYLqh0C&lpg=PP1&pg=PA16#v=onepage&q&f=false
http://elektrotanya.com/files/forum/2009/10/e04a036.pdf
http://welecw2000a.sourceforge.net/docs/Hardware/Aktiver_Tastkopf_mit_OPA659.pdf
http://oliverbetz.de/hit/hit_e.htm