dangerous profession

In the end every brewer has to figure out for himself how to deal with yeast, hops, temperatures and so on. Given the exact same recipe there can be significant differences in tase.

--
Regards, Joerg 

http://www.analogconsultants.com/

My oscillator has a varicap, part of the PLL. Of course, a varicap has a tempco the varies with the applied voltage!

Smile when you say that.

It's impressive how isothermal a 10-layer board can be. Lots of copper!

We need to rev the board, so I could add heater resistors and a dedicated temp sensor under the oscillator. With luck, we'd never have to use them. Depends on whether my tempco tuning is reproducible in production.

Another reason to spin the layout: I was having time-delay jitter going through one FPGA, synchronous to a switcher in the opposite corner of the board. I couldn't understand that, so I disabled the switcher with some difficulty and hacked in a linear reg. That fixed it.

A real pain to do. I had to drill out some vias to disable the switcher.

Much of that jitter is probably from the scope.

Just curious, but do people buy competitor's draft beer to steal the yeast?

d

es

ckenhefe-115-g

if it isn't pasteurised an filtered

beer

Yeah, another error term and probably non-linear.

We've had similar effects in pulsed Doppler ultrasound systems. Those are like a princess on the pea when it comes to jitter on any of the clocks. What I sometimes did is run a coax or (after relayout) a trace over to the oscillator or stage that was affected and coupled in opposite phase via a sub-pF ceramic cap. The guys usually thought that was voodoo but it worked reliably and most of all repeatably so production didnt have to worry about it.

Do you have a before-after comparison?

--
Regards, Joerg 

http://www.analogconsultants.com/

Harvesting from commercial bottles has become tough. Big breweries try to make sure there is no to little viable yeast left. Not so much for "yeast theft" reasons but to avoid exploding bottles (bottle greneades) when stored in warm temperatures.

--
Regards, Joerg 

http://www.analogconsultants.com/

I don't have a good "before" pic handy. P-P jitter was about 2x what it is now.

I noticed that the jitter would squirm as a function of trigger rate. The heterodyne frequency corresponded exactly to the switching frequency of one of the LTM8078 switchers (which are themselves remarkably frequency stable.) It was the 1.8 volt Vcc_aux power supply to two FPGAs, one directly in the delay path.

I doubt that Vcc_aux affects prop delay much; it doesn't for DC changes. It may do nasty capacitive things inside the chip.

This Xilinx chip is very sensitive to core voltage, like -5 or -10 ps per millivolt.

The whole front end of this box could have been ECL, but that takes a lot of room and power and dollars.

My goal is to make a delay generator with 1 ps RMS jitter. I can probably get below 5.

We'll announce this soon.

--

John Larkin         Highland Technology, Inc 

Science teaches us to doubt. 

  Claude Bernard

Thank u for keeping in mind that 10-12% of the adult male population is color-blind and that labels on heavily-used buttons wear off

Prospecting in abandoned mines in the Southwest for preserved denim jeans from the 1800s is a dangerous job, but well-preserved 150 y/o American denim jeans are a hot item on like the Japanese collectors market and sell for up to $10,000 per I guess

Speaking of "out of..".

As for you:

Cool. I've long used the P400 very happily as you know.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
http://hobbs-eo.com

I'll send you a P500.

I'm especially happy with the GaN output stage. Vhigh can go from -5 to +20, and Vlow +-5, very clean all the way. If I showed you the circuit, you'd laugh and say "that can't work."

I made a simple pulse generator with that same output circuit, just to stay amused during the early lockdown.

If you define a plane with pulse rate on one axis and voltage on the other, there are inhabited regions, Schmoo diagram style, like for instance avalanche transistors in one blob, mosfets in another. We may have our own little turf, say 100 MHz and 100 volts. Somebody might want that.

--

John Larkin         Highland Technology, Inc 

Science teaches us to doubt. 

  Claude Bernard

Looking forward to trying it out! We're planning to use the P400 to calibrate a time-stretcher for geophysical lidar, where you want many samples in a short time but the rep rate is slow. We'd certainly use the swoopy new one if it gets here in the next couple of months.

I feel that way about some of your other circuits too. Fortunately I know enough not to start a fight when the data goes the other way. ;)

That regime sounds pretty physicsy, but there are a fair number of interesting electron-microscope-style applications, I expect. Dunno if any would lead to sales volumes that would excite you.

I really like instruments whose limits I don't have to worry about.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
http://hobbs-eo.com

The LCD is black on white. Each button is single color backlit with obvious text.

You're straining to disapprove of a beautiful box. Why?

You'd better not buy one.

We're curently implementing the "trains and frames" option. A "train" is a series of programmable pulses on all channels, after a trigger. "Frames" is a series of timing settings that change every trigger. They can be combined.

Our problem isn't so much how to implement it, but how to explain it to users and provide them a language to program it. We don't want a zillion emails and phone calls from grad students or whoever.

Shooting and killing and explosions and hatred is mostly what Hollywood does nowadays, while preaching gun control and peace and love.

My reward is purchase orders.

Almost like they've learned that overestimating American's intelligence is rarely profitable.

That is to say they know their market.

Or China's for that matter, which will soon make up the bulk of Hollywood's market, if it hasn't already. Much English-language nuance doesn't translate well to Mandarin. Kind of like telling jokes to engineers

?????

No I was actually thanking you

My Rigol scope for example uses one button called START/STOP to start and stop and uses a green/red LED to indicate which mode it's in

10-12% of the adult male population is color blind with red/green the most common!