GPS 1PPS

May 15, 2016 56 Replies

Yes and no -- If you use a PLL with a linear time-invariant loop filter, then it'll certainly take a huge number of seconds to spin up.

If getting down to the best possible number in the least amount of time is important, you can speed things up considerably by using a Kalman filter -- it's almost a classic use case, and you've got an FPGA in the mix. I'd have to, like, expend effort to get exact numbers (and I'd be guessing on the oscillator stability anyway), but you're talking about getting down to less than 10ns RMS error in well under a minute.

Tim Wescott Wescott Design Services http://www.wescottdesign.com I'm looking for work -- see my website!

I've been in and out with health issues but one of my cow-orkers dropped a spec, from a customer, on my desk Friday. Inside, it's really four different products with at least two completely different designs. Each will be >220x150mm boards with >1000 components. I have until 10:00AM tomorrow (Monday) to read the spec (~100 pages) and make a proposal.

Yikes. Don't waste too much time on s.e.d., or eating or sleeping. Do you need to price it? That's the scary part. If it's a crisis, you can edge on the high side.

If they are like my customer, it brewed for a few months until it became a crisis. Oh well, it's business.

John Larkin Highland Technology, Inc lunatic fringe electronics

We are all interested in electronics, but we share the impression that John Larkin isn't interested in electronics as such, but rather in tinkering wi th electronic hardware until it produces results that can impress other peo ple.

Consequently we don't say flattering things about John Larkin often enough to keep him happy, and he finds us obnoxious - obnoxious enough to ignore a nything we do post about electronics (since it's unlikely to contain any fl attering references to stuff he's done).

Bill Sloman, sydney

John is a very odd person in that he seems to be a rational thinker in many way, but in other ways he becomes highly opinionated and refuses to consider any point of view but his own. Whatever. He is just one of many here. This group has a huge amount of noise and JL is just another component.

Rick C

No need for costs yet. Just a first round of spec tuning and feedback. It's easy to ask for changes at this point but it gets harder fast.

We can't error on the high side. We'd never get business. If they need costs they'll have to allow enough time to get decent numbers.

Yep, no doubt it happened here too. It's standard operating procedure.

I'm happy to see you put them to good use. Do you have measurements of return loss or reflections you could share?

Jeroen Belleman

On Sun, 15 May 2016 23:27:48 -0700 (PDT), snipped-for-privacy@ieee.org Gave us:

Except that you quote and repost his horseshit to the tune of 280 line posts.

You are almost as stupid as he is.

I haven't built them, but will soon. But we work in time domain, so I'll do TDR testing, not that sine wave S-param stuff.

Mini-Circuits has a new line of absorptive filters. Theirs are symmetric, absorptive at both ends. I need a filter that's absorptive on one port, reflective on the other, and yours does that!

John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

So, you're too lazy to scroll but not too lazy to bitch, right? Go find a group that meets your requirements and find something there to bitch about. Nobody here asked your opinion, DipShit.

On Mon, 16 May 2016 18:32:48 -0500, John S Gave us:

F*ck you, cave boy.

Usenet posting protocols and community conventions have been quite clear for decades. Whereas you have obviously been quite oblivious for decades.

No, thanks. You're not my type.

On Tue, 17 May 2016 08:07:24 -0500, John S Gave us:

Too stupid to see an insult too. It does not get any more retarded than a cave boy wannabe.

You reply was archaic and outmoded even in the seventies, dumbfuck.

It served its purpose, which was to yank your chain. You're easy.

On Tue, 17 May 2016 08:20:57 -0500, John S Gave us:

The response is now appropriate...

You're not my type, retard boy.

Your opinion means nothing.

That's parroting my response. You got nothing better?

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