Close

Hoarders' delight

A project log for Active scope probe with no dedicated power supply

Using the probe test point to power a ultra-low capacitance, high-input-impedance amplifier, essential for accurate analog measurements!

Yann Guidon / YGDESYann Guidon / YGDES 04/13/2016 at 10:322 Comments

Do you know that little voice that says "hey it's a cool bargain, don't miss it, you WILL need this junk one day, I am sure !"

That was almost 13 years ago and I came across bargained ISA NE2000 cards. I had read somewhere that someone had hooked such a board to a PIC16F877 and written a network stack...


Fast forward to 2016: I use Wiznet chips, FPGA and the YASEP has been emulated and simulated. But I need BNC connectors and Ts. Wait, I don't need to go outside to the last electronics parts shop of Paris. I can desolder them from those boards :-D

The T were provided but I must have taken them all from the boxes, as I found a couple in the scope probes' box. Well, 2 will be enough for a prototype.

Discussions

K.C. Lee wrote 04/13/2016 at 12:35 point

The big GTS thingy is an isolated DC/DC converter for powering 10Base2.  You also get a high voltage cap and sometimes a spark gap transorb.

  Are you sure? yes | no

Yann Guidon / YGDES wrote 04/13/2016 at 12:46 point

Yup !

But they are not rated for the power and efficiency ranges that are needed...

Anyway, that's one more reason why I don't throw them away. Hey, I bought them in the first place :-D

Now, most of those parts are undocumented to me :-/

  Are you sure? yes | no