Re: [time-nuts] Quartz Crystal Motional Movement

Hi The key trick that is often missed while watching it done is the need to set it (tune it) to operate at the frequency you are looking for. In other words, if you are testing a 4 MHz crystal, you need to first tune the machine to 4 MHz. If you truly have a bag full of “mystery parts” that’s

Re: [time-nuts] Quartz Crystal Motional Movement

> Hi > > Might be a little more fun if it showed the proper way to use the 150B (or > any similar device). > > Bob Hi Bob, Can you tell those of us with those cool Saunders 150B crystal impedance meters how to do it right? /tvb ___ time-nuts

Re: [time-nuts] Quartz Crystal Motional Movement

> The highest Q I remember seeing were BVA's that reached 2e6 to 3e6 @ 5MHz What determines the Q of a crystal? Is it atomic level impurities? Crystal defects? ... How has that changed over time? Is there a Moore's law for crystals? How does the quality of crystals used for timing compare

Re: [time-nuts] Quartz Crystal Motional Movement

Hi Every paper I have ever read on the intrinsic Q of quartz makes the claim that Q * F is a constant ( Q goes up as frequency goes down). Unless blank diameter gets in the way, this has been true for any crystals I have ever used. Q does change as overtone changes, but that is not related

Re: [time-nuts] Quartz Crystal Motional Movement

> The highest Q I remember seeing were BVA's that reached 2e6 to 3e6 @ 5MHz > > Attila Kinali Hi Attila, Don't forget about University of Western Australia's multi-decade gift to the world -- whispering gallery Cryogenic Sapphire Oscillator (CSO) -- which have Q near 1e9.

Re: [time-nuts] Quartz Crystal Motional Movement

On Sat, 25 Jun 2016 02:48:04 -0700 Bryan _ wrote: > Quartz Crystal motional movement... > https://youtu.be/y-rCgumTn4Q Some additional info: The Q of a crystal decreases with frequency. For a given crystal slap and production process, Q*f is almost constant, with a peak

Re: [time-nuts] over-determined clock solution

In this receiver mode all the satellites are used to compute the timing solution. See page 80 of the 2012 Thunderbolt-E manual: This mode is available when the position of the antenna is known and is stationary. Timing receivers usually

[time-nuts] pick and place problems/design (was: OT stuffing boards)

I do mostly digital stuff and 80% of my resistor usage is 10K, maybe 10% 1K, a couple of other values are 9%, random values make up the remaining 1%. For caps I use 0.47uF 0805's most of the time and 10uF (can't remember the size). Why 0.47 uF you may ask? Well, I thought I was buying

Re: [time-nuts] over-determined clock solution

Try overdetermined as one word. Also include GPS in the search string. Google has many hits. In timing receivers, once the position has been determined the receiver switches to using timing information from all of the satellites that it can see. Like the man with too many clocks, the clock time

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

Hi > On Jun 25, 2016, at 12:56 PM, Chris Albertson > wrote: > > At home I have a parts bin and I find I need to stock about two dozen > resister values. Ok, chip resistors run about ten for a penny. Buy 1,000 of each for a buck a value. So far you have spent $24

Re: [time-nuts] Quartz Crystal Motional Movement

excellent vid, Bryan! On 2016-06-25 03:48, Bryan _ wrote: Quartz Crystal motional movement... https://youtu.be/y-rCgumTn4Q -=Bryan=- ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] over-determined clock solution

On 6/25/2016 9:07 AM, Steve wrote: > The phrase "over-determined clock solution" is used in the Trimble > Thunderbolt user manual in describing operation of the Thunderbolt GPS > receiver. The manual does not discuss the phrase in any detail, > appearing to assume the reader understands its

[time-nuts] over-determined clock solution

Trimble can operate in a 3D positioning operation mode that works that way. But their "overdetermined clock" mode is what most people call "position hold" mode. Set the receiver to "overdetermined clock", and the lat/lon/alt coordinates it sends never change. As far

[time-nuts] OT stuffing boards: was GPS interface/prototyping board

If OpenPnp generates a gcode file for a particular CNC controller (say Linux CNC) my program can easily translate it into something pretty much any other CNC machine can read (including some machines that have not existed for over 40 years). It would not be hard to add the ability to read a

Re: [time-nuts] pick and place problems/design

There is a "hobbY" pick and placer called LitePlacer that meets a lot of your criteria. http://www.liteplacer.com It works on cut strips, not reals, it will handle random placed parts on the table top, but so far I don't think it automatically figures out what they are. But you can put a

[time-nuts] over-determined clock solution

It is basically what most people call "position hold mode" where the receiver has known (and accurate) fixed coordinates. With lat/lon/alt known, it can solve for time with just one satellite visible. Or, if more than one sat is visible, its time solutions can be more accurate because noise

Re: [time-nuts] over-determined clock solution

stev...@suddenlink.net said: > The phrase "over-determined clock solution" is used in the Trimble > Thunderbolt user manual in describing operation of the Thunderbolt GPS > receiver. > What does "over-determined clock solution" mean? You are trying to solve for X, Y, Z, and T. (or the polar

Re: [time-nuts] over-determined clock solution

Hi As far as I know, it simply means that there are more satellites in view than needed for a fully accurate time to be determined. If it needs four sats to come up with a valid location plus time, it has five or more. If it has five but is not happy with the location solution (still in

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

At home I have a parts bin and I find I need to stock about two dozen resister values. I can buy a pack of 1,200 resistors for about $12 and there are all 24 values in the package. If I had to spend $20 per value I'd have to spend $480 and some how find space to store 24 reels.Yes, one

[time-nuts] over-determined clock solution

The phrase "over-determined clock solution" is used in the Trimble Thunderbolt user manual in describing operation of the Thunderbolt GPS receiver. The manual does not discuss the phrase in any detail, appearing to assume the reader understands its meaning. An internet search on

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

Hi Even on a “real design” desktop pick and place, vibration is an issue for parts moving around. The same is true of parts “squirming” on a pick head as it does it’s thing. Part’s aren’t as flat as you might think they are and you can only get just so much vacuum. Lots of grubby design

Re: [time-nuts] Quartz Crystal Motional Movement

Hi Might be a little more fun if it showed the proper way to use the 150B (or any similar device). Bob > On Jun 25, 2016, at 5:48 AM, Bryan _ wrote: > > Quartz Crystal motional movement... > https://youtu.be/y-rCgumTn4Q > -=Bryan=- > >

[time-nuts] Quartz Crystal Motional Movement

Quartz Crystal motional movement... https://youtu.be/y-rCgumTn4Q -=Bryan=- ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

Hi If you are doing the sort of boards that started this discussion (100+ parts per board / 5 to 10 boards) a reel of bypass caps will get used up pretty fast. Shame on you if your designs don’t standardize on a bypass cap or three and about five resistors. Resistors reels of 10,000 are ~$10

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

And try to tell transistor A from transistor B from diode C when they are all upside down. A moving head design can be made to pick up parts off of reels on all four sides. But it takes more table space. Which is money. As someone else said, you need Z rotation, which isn't as easy as it

Re: [time-nuts] OT stuffing boards: was GPS interface/prototyping board

Hi The vision stuff comes in a few ways: 1) Your board needs to be aligned to the machine. There may or may not be accurate holes in the board to do this. Doing it with holes still leaves you with the need to get the board location “into” the machine’s coordinate system. 2) Tapes come in

Re: [time-nuts] OT stuffing boards: was GPS interface/prototyping board

On 25 June 2016 at 05:28, Mark Sims wrote: > Vision system is nice, but a decent CNC is more than accurate enough for > 0402 sized parts. Again, surface tension is your friend. There's often more positional slop within the tape pocket than the pin pitch, for components

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

Many parts can't be recognised visually. Capacitors are the obvious example. On Sat, Jun 25, 2016 at 6:11 AM, Chris Albertson wrote: > The ideal hobby use pick and place machine would be very different > from a commercial machine. Lets say I want one board made.

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

Hi > On Jun 24, 2016, at 11:56 PM, Attila Kinali wrote: > > On Fri, 24 Jun 2016 13:59:58 -0500 > "Graham / KE9H" wrote: > >> Lots of problems to be solved... > > Most of these problems are easy: > >> How do you take loose parts or cut tape or tape

Re: [time-nuts] OT stuffing boards: Saving the thread

On Fri, Jun 24, 2016 at 9:16 PM, Bill Hawkins wrote: > The problem is editing out all of the redundant material. It's tedious > by hand. > > Anyone got a program to do that? Say, in perl . . . textsoap It's made just for this purpose, turning emails and the like into clean

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

> Also how many hobbyists are going to have reels of parts? Reels of small resistors or caps are ballpark of $20. I'd be happy to buy one for any part that is likely to get use multiple times on a board and again on the next board. -- These are my opinions. I hate spam.

Re: [time-nuts] pick and place problems/design (was: OT stuffing boards)

The ideal hobby use pick and place machine would be very different from a commercial machine. Lets say I want one board made. What I want to minimize is my time. With a conventional machine by FAR most of my time is spent setting the machine up. In fact setup is so slow that for smaller PCBs