On Wed, 4 Nov 2009 22:11:38 -0000, "ian field"
wrote:


"Jim Thompson" wrote in
message ...
On Wed, 04 Nov 2009 15:24:10 -0600, John Fields
wrote:

On Wed, 04 Nov 2009 12:39:06 -0700, Jim Thompson
wrote:

On Wed, 04 Nov 2009 13:58:37 -0500, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

On Wed, 04 Nov 2009 10:34:20 -0600, John Fields
wrote:

On Wed, 4 Nov 2009 13:17:24 -0000, "ian field"
wrote:

What would be the minimalist circuit blocks for a frequency domain
sample
and hold?

What I envisage is the sampling triggered by a tone that exceeds a
pre-set
threshold and continues to generate a copy of the tone until reset.

---
I'm confused...

What do you mean by 'sampling' and what do you mean by 'threshold'?


JF

Wasn't there at one time something called a "bucket brigade" that
could take snap-shot recordings?


Digikey was still selling the Panasonic 'Bucket Brigade Analog Delay
Lines' a few years ago.

Of course, the best response to the OP is, "WHY?"

---
I don't much care about why, since the fun for me is doing the design.
:-)

Seems what the OP wants to do is monitor a sine wave source and then
when the source's tone gets to some "threshold", have the device
monitoring the source generate that tone forever.

But, who knows for sure, since his "specs" were pretty sketchy?

JF

Indeed! Is the frequency always the same value? Or a variety of
frequencies? Why not a simple tone detector?


If it was only one frequency I could just build a sound activated
oscillator.

Why do you need to continue the tone?

Range of allowed input frequencies?

...Jim Thompson
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