Logic Level MOSFET

The first two certainly don't sound Irish to me...

My dad, the Larkin, was half German, and my mom was 100%. There were dark rumors of some French contamination somewhere along the line, but nobody wanted to say much about that.

The Brat is 0.25 Italian on top of all that, some serious American hybrid vigor.

John

...Jim Thompson

So did she speak like "Vee, da peeple off Kahlifohniah ..."?

If she was still alive, she'd get a kick out of the Lutran Airlines Announcement:

Same here. But then my grandma passed away before I could probe those rumors deeper.

very

No, they both spoke Yat, the working-class dialect of New Orleans, named for the universal, Aloha-like greeting "where y'at?" [1]

John

very

Yesterday I spoke with my English teacher from 30-some years ago. To my surprise she stayed in Germany. But most interesting was that her N'Orleans accent seems to be almost gone by now. Amazing.

She said that when she was a kid they mostly spoke French there.

I predict one day you'll come to respect and treasure your own unique New Orleans upbringing, culture and history.

Doubt it. The place really sucked.

John

Not interested in the old and inferior way of doing it...

It is no solution at all. PWM through a substantial length of wiring harness, with unlimited dV/dt, the one size fits all "solution"? Forget it.

Things are more bulb-centric these days...too complicated for you?

Fred, there's an entire universe of stuff out there that you're not interested in.

Well, I did design the dimmers (4 GHz bandwidth dimmers) for this,

the world's biggest laser.

Gosh, if I was a smart as you are, imagine what I could do.

John

Brag and not deliver?

Not interested in hearing about it...

God help us....

You're too dumb to be very imaginative...

One doesn't often see the words dimmers and 4GHz together. Explanation, please?

NIF has 192 beam lines, each a big pipe full of flashtube pumped amplifiers. The input to each line is a fiberoptic blip of light at about 1100 nm; it makes 4 free-space passes through the slabs and emerges at the and, goes through a tripler, and enters the target chamber as UV. It all converges on a little gold capsule full of tritium and stuff.

The beamlines are grouped as 48 quads. In the MOR, the master oscillator room, there's a master laser that feeds 48 of our modulator boxes. Each box has a 4 gs/s 16-bit arb and a programmable 1 ps resolution square-pulse generator, and a bunch of bias stuff. We drive a 2-stage Mach-Zehnder optical modulator, one stage being a square pulse gate and the other being an arbitrary waveform. The output of our boxes gets optically amplified and is then run to the 192 big amps out on the floor. The idea is to precisely shape the waveforms of the light that ultimately whacks the target with about 1.5 MJ of UV.

What's a little unusual about the arbs is that they are triggered and generate their one-shot waveform with a couple picoseconds of jitter. The whole system - arbs, modulator, downstream amps - is fairly nonlinear, so they fire the MOR stuff 24/7, at 960 Hz, and sample downstream optical signals, and close a loop on the desired waveforms. So everything up the the main flashtubes is run and tweaked continuously.

The arb is done by sheer brute force. There are 140 gaussian impulse generators, each a delay circuit, a gaasfet, and a shaping network. Each is dac programmed for amplitude and time of peak, and all 140 are fired at 250 ps intervals and summed. If we had to do it again, we'd probably go with a ring of staggered-triggered medium-fast dacs, mux'ed somehow.

We also generate some 90 ps wide fiducual pulses, for aligning shot diagnostics.

The math of summing gaussian impulses is interesting. It has analogies to making arbitrary shapes from power or Fourier series.

John

I'm guessing phase dependent switching light like in triac/diac household dimmers.

D from BC

People who think they're perfect are particularly annoying to those of us who are. ;-)

Cheers! Rich

So, do you expect to see break-even in your lifetime?

Thanks, Rich

I think they expect net fusion energy greater than the laser light input to the target chamber, but that's far from wall-plug break-even. As they like to say, they expect about as much fusion energy as there are calories in a jelly donut.

John

I'd like to hook up with a sorceress, and conjur up a Zero Point Daemon. ;-)

Cheers! Rich