On Wed, 29 Mar 2017 11:42:41 -0500, Foxs Mercantile
wrote:

On 3/29/2017 11:33 AM, Jeff Liebermann wrote:
If you must use tubes, I could probably design a cascode
Nuvistor RF probe for the occasion.

Duly noted so your ego remains intact this time. ;-)

Thanks. It's rather difficult to be diplomatic and insulting
simultaneously. I'm sure you're now planning how to retaliate.

http://bama.edebris.com/download/ameco/pcl-p/AMECO%20PCL.pdf

Nope. That's an RF amplifier. I went looking for an RF probe
schematic based on a Nuvistor, but couldn't find anything. There are
some TEK oscilloscope front end circuits that use a Nuvistor, that
could probably be converted into something useful. Basically, one
needs a broadband impedance converter. Cascode (common emitter
driving a common base) design seems right. It would take two 6CW4
Nuvistors, a length of 3/4" copper pipe, and some high voltage. If
that's to messy, a single tube in a cathode follower derangement
should work. It might get warm enough to be uncomfortable, but that's
the price we pay for working with tubes.

Nuvistors are cheap on eBay but sockets are pricy:
http://www.ebay.com/sch/i.html?_nkw=nuvistor
Hmmm... LTSpice models available for various Nuvistors.
Never mind. I don't need yet another project.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558