an Alibaba seller comes through, again.

More pedestrian-ly Ali seems to be the only place to get small quantities of alphanumeric LED displays (the kind with the diagonals in addition to 7 segments and decimal point) at a reasonable price

LIGO?

You've determined it's real from simply measuring its characteristics. Is that really good enough to bet your life on it?

Laser Interferometer Gravitational-Wave Observatory.

Somebody more widely read than Cursitor Doom - like the average five-year-old - would have heard that they have now detected gravitational wave signals from black holes and neutron stars colliding and fusing.

LIGO, Laser Interferometer Gravitational-Wave Observatory. Gravitational waves.

Yes. A counterfeit MOSFET couldn't do that. The roll of labelled parts was immediately sent out after my order. No time to prepare a fake-labelled part. Why do that for 38 cents per part? No sir.

He should've tried asking it directly, you have to shout at them though most semiconductors don't hear too good.

Did you actually work on the LIGO project ? That would be so CooL !

I used to live not far from the one in Washington state when I worked in Richland, WA.

boB

No, I didn't work on anything in the current LIGO observatories, that would have been very cool. But I am working with a group to improve the performance of some optical modulators, etc. This involves increasing the HV amplifier's slew rate, or making a higher bandwidth, or with much more mid-frequency loop gain. Apparently, as well as the LIGOs are doing now, they're working hard to further improve them. I'm creating an advanced version of my AMP-62 design, which some of you know about. I've given away bare AMP-62A boards and am creating a new AMP-62B version.

Got a link to that? It doesn't google.

Ligo must have the lowest long-term s/n of any science experiment, except the ones with zero results. It took a lot of patience to get the first clear gravity wave.

Are you looking for an AMP-62 link? Here's one that's about 3 years out of date. I'm upgrading the stuff now.

Stacked current sources! But with LND150s, it works.

Yes, but the scheme on the lower left of the diagram works much better, evenly distributes the dissipation. Along with changing to BSS126, and 10x higher critical node pullup current, get dramatically faster slewing.

Would some newer wide BG devices like GaN or SiC be better for even higher slew rate ? I would think that John Larkin is also using some of that stuff for his pulse generators ?

Would some small caps across those two resistors help, reduce Miller effects in the upper fet? Maybe just across one resistor, since Cd-g is already there.

Sometimes adding inductors helps, if you can keep that under control.

You can also completely float the output gate drivers, but that takes more parts.

Bootstrapping is fun too. Sort of the same thing, I guess.

Some of the smaller EPC GaN parts are interesting, but only go up to about 200 volts.

I think someone is making 600 volt GaNs now.

I'm using the Cree SiCs, but they are mostly big for this sort of amp.

I've been using SiC for my 8ns HV pulser pickers, and I selected the smallest of the parts on offer, which did well driving 50-ohm coax with 6A switching. But sadly they don't offer small parts, so the smallest ordinary MOSFETs have less capacitance than the smallest SiC parts.

And there were a lot of pre-LIGO experiments.

Govert Schilling is Dutch, but he writes excellent English, and his book is a brilliant history.

I've been reading Physics Today on and off for quite a while now, and his book reminded me of quite a few articles that got published there. There were quite a few "resonant bar" gravity wave detectors, and none of them ever detected anything.

Cold fusion research hsn't been going on for anything like as long.

Then they probably picked up your footsteps when you got up in the middle of the night to pee.

Rick C.

Tesla referral code -

That's why LIGO systems are paired. Only the noise that correlates between two LIGO machines that are a long way apart gets looked at.