BOZ with current source?

[Decker]

I can't be the first to wonder about this, but I did a search and found no answer. Has anyone experimented with a current source in place of R104 in the BOZ circuit? If so, good, bad or indifferent?

 

[GRollins]

You'll end up with vast amounts of gain that you can't possibly use.
I don't remember the gain of the stock SOZ, but it's probably something rational like 10 or 20dB. If you go to an active load (fancy name for replacing the resistive load with a current source) you'll end up with...oh, I don't know...at least 50dB, and quite likely more (80dB?...just guessing).
Okay, you could burn off the excess gain in any number of ways, the first one that would occur to most people being negative feedback. Or you could load the back end down with a resistor. Or you could degenerate the booger. Or...
Or you could just use a resistive load and be done with it.
That's not to say that you couldn't learn a lot from the experiment, though. Knock yourself out. It wouldn't even be all that difficult to rig up.

Grey

 

[Decker]

Thanks for replying! My BOZ actually has too much gain for my system as it is, so the current source is probably not a good idea. I assume the same problem would occur if I used a choke with about 1k resistance? The BOZ sounds good as is; I was just thinking about ways to "improve" it.