Cold testing

Out comes the scat reference. Perhaps you should go chat with your butt-buddy JF.

Clean toilets? We got that some time ago, Dimmie.

Wow! Such antipathy. You should watch your blood pressure, Dimmie.

More scat references from Nymbecile.

No, we drive our quiet stuff with switching supplies.

This is a programmable pulse generator with three switchers (one a home-made charge pump) and an ARM processor inches away from the fast stuff.

I couldn't measure the jitter with instrumentation that has a 3 ps RMS noise floor. I need to try again with better gear.

Of course picosecond precision is hard. That's why it's fun, and why we can charge interesting prices for it.

--

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com   

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME  analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

Going into and out of an FPGA can easily introduce 30 ps/degC delay and tens of ps of RMS jitter.

--

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com   

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME  analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

Long before that came the engineering, idiot.

And you have been on the same retarded bandwagon the keithkiethstain captains, with your retarded claims that I 'sweep floors'.

Make up your mind, you retarded, sub-human bitch.

That is a mistake. No wonder you have so many jitter and noise abatement issues.

Then again you probably do not have anything that could be influenced by

5th through 14th order harmonic noise effects, and are far too stupid to know that you may need to abate it.

You are not going to win this one either, John.

Everybody sweeps floors now and then. But I think you're a tech who doesn't understand things at any depth. That would be fine, except that you claim to know things you obviously don't, and you are continually foul and offensive and threatening and AlwaysWrong. Sounds like massive insecurity to me.

--

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com   

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME  analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

But I don't. Fast stuff uses lots of current at low voltages. The thermal issues from linear regulators would be lethal, whereas using switchers just needs some care.

All you need is to do tha math, and use sensible PCB layout.

I can't measure the jitter on this one. It worked as expected, first etch, with one small kluge that had nothing to do with power supply noise.

Show us something that you designed.

The customer pre-paid for 20 of them. I won before I even designed it.

--

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com   

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME  analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

Me too. We used a regular cooler, augmenting the insulation with styrofoam.

Don't remember whether I used a fan. I left the chest to steep, removing moisture, then loaded. Reached -40C without too much trouble, monitored with a t/c tied to one of the assembly's heatsinks.

The assembly was ~30x30 cm.

There was a lot of dry ice left over. It being New Orleans, we threw a party with it--lots of bubbling drinks.

--
Cheers,
James Arthur

the assembly's heatsinks.

Reflecting, I'm not sure where the t/c was connected. I vaguely recall trying various points, to see if the chest was uniform.

--James

Particuularly if you're crossing onto the on-board clock boundary whether it's a PLL or DLL.

This kind of post is all a retarded f*****ad like you is good for.

That was not an immature remark, that was a spot on declaration of what you are.

Grow the f*ck up, Chuck, you make me want to upchuck.

You dopes have no clue about standard sync signals?

Just so you know, these do not pass through an FPGA. FPGAs control the phase shifters which line every channel up.

I know it is a hard concept for you twits to follow, but all of these pipes stay on microwave amps, splitter/combiners, etc.

You clueless dopes are one sorry group.

I can readily see what John Fields' observations about Larkin indicate.

You can't get a damned thing until your hand is held all the way through the process and even then all you end up with is a cursory overview of it, and next to zero grasp.

you

Tell us about them DimBulb, and how they cure jitter.

Moving goals again, Dimmie?

AlwaysWrong.

You two are peas in a pod. Neither can do simple math and neither have a clue.

There's only one thing you can get in your hand, Dimmie.

Mr. Fields has more on the ball than a retarded, know nothing punk like you ever will.

When was the last time YOU posted a schematic into THIS, A DESIGN group?

Oh... That's right, you are too goddamned retarded to make a valid, on topic contribution to ANY groups, much less this one..

Mine is calling retards like you exactly what you are. A characterless, honorless asswipe.

He posted one today.

You are a loser, you piece of shit. You possess ZERO karma.

Good job of showing it too.

Impossible. He's your twin, AlwaysWrong.

When have you, DimBulb? Oh, that's right, schematics take math.

AlwaysWrong.

That's a "contribution", Nymbecile?

Where's yours?

It runs over your dogma almost daily, Dimmie.

Thank you, AlwaysWrong.

ts

CO2

f

Dry ice seems like the answer to me. I've heard you can make your own with a fire extinguisher, and a cloth bag. (I've never done it, but plenty of videos on the web.) Temperature control will be a bit more work. But it sounds like Robert may be able to take data 'on the fly'.

George H.

The moment you crack the valve on the extinguisher, you lose ALL of the contents, even though you may stop short of using it all, the rest will leak out.

ALso, they are NOT cheap to fill because you also pay for the certification.

It is ONE HELL of a lot cheaper to simply look up, find, and visit an "Airgas" company or welder's gas supply and get a CO2 tank or simply find and buy dry ice itself.

It is far cheaper.

Thast is another reason to use block form because THAT IS controllable.

One must also immerse the circuit in something to keep the H2O condensation from forming.

Try this:

Robert Baer schrieb:

Hello,

reaching -55 °C with dry ice should be possible using an isolating box. If you use dry nitrogen from a pressure tank to displace all air before, there should be no moisture. Dry ice cools down to about -78 °C.

Bye

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Sure, I agree. For some reason it sounded like Robert didn't want to go and pick up dry ice though.

.

OK, Dry air would work fine too. He might rig up something to pass the air through some filter (molecular sieve?) in contact with the dry ice before it goes into a box with the electronics in it... though this is starting to become complex.

If the box holding the electronics could be air tight, then the small amount of water in there may not be a problem... maybe some cold finger that chills first and sucks up all the water vapor. (a sort of a getter?)

George H.