Re: differential probes

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

Hi Jimmy, Finn, and All,

This is the present schematic and parts list I have in mind for the 
differential probe.  I have NOT assembled or tested it yet!

http://hot-streamer-dot-com/temp/DiffProbe-5.gif

http://hot-streamer-dot-com/temp/DiffProbe-5p.gif

It is still just using the basic 150MHz TI  THS4151ID differential 
amplifier IC and other straight forward parts.

One thing I am "trying" to add is a front end that can take a hard hit.  I 
will have a system ground stud and MOVs at 1800 volts each.  These will be 
fused with low current but high voltage fuses.  The idea is if you get a 
say 20,000 volt cap on the input, the MOVs will clamp it and the fuses will 
break the circuit away without damaging anything like the scope.  Since we 
play with big voltage stuff, I think super protection like this is a real 
good idea to have.

So that's were I am at the moment on this...

Cheers,

	Terry