robb wrote:

snip



So it really is not that great an ESR schematic then ?

No, it *is* a great ESR meter schematic, for what it is
intended to be. It is something a hobbyist can put together
for a few dollars that will work for most of the hobbyist level
usage it is likely to see. It is great for that.

It is not a laboratory instrument. More advanced hobbyists
may insist on more advanced instruments. That's fine for
them.

Put the thing together, and enjoy. It will serve you well
until your experience/understanding/usage/whatever grows
beyond what the meter can do.

If somone has a better approach and a better schematic that
matches your present construction ability, and is as
inexpensive, then go for that schematic instead of the one
you are working on now.



Well i really wanted to build something good and would rather not
build a crappy ESR.

It is not crappy. You will not waste a penny of your
investment in it, nor will the time and effort you
put in be mis-spent. If nothing else, it is a good
learning experience, but it is far more than that.
You get a meter that will locate bad capacitors, give you
an introduction to the idea of esr value, give you some
interesting sub circuits to learn about and could save
you money and time in repairing equipment, if you are
into that.

Ed


Then I am dropping back and will read through comments made. I
will probably re-draw schematic in OpAmp block form as in the
original schematic then figure out what the pieces are doing by
reading through the OpAmp application notes Joerg pointed to etc
etc etc....


Thanks for the help John.
I hope some of you experts are going to be around when i ask
"what for is a resistor ?" and other such basic questions.

robb