Hi Cool !!!
Bob > On Nov 23, 2016, at 10:48 AM, John Ackermann N8UR <j...@febo.com> wrote: > > Counters with resolution below 1 nanosecond are difficult. They require > either outrageous clock speeds, or interpolators that are typically a bunch > of analog components mixed with black magic and stirred by frequent > calibration. The very best single-shot resolution that's been commercially > available is 22 picoseconds in the HP 5370A/B, with jitter somewhat more than > that. My 5370B has an one-second noise ADEV of about 4x10e-11. > > With the help of some very talented friends, I've been working on a new > counter called the "TICC" with <60ps resolution and similar jitter, based on > the Texas Instruments TDC7200 time-to-data-converter chip. The one-second > noise ADEV is about 7x10e-11, not much worse than the 5370, but here's the > trick: the TICC is an Arduino shield (mounting on a Mega 2560 controller) > that weighs only a couple of ounces, requires *no* calibration, and is > powered from a USB cable! > > The TICC is implemented as a two-channel timestamping counter. That means it > can measure one or two low-frequency (e.g., pulse-per-second) inputs against > an external 10 MHz reference, or it can do a traditional time interval > measurement of one input against the other. It can also measure period, > ratio, or any other function of two-channel timestamp data. (And by the way > -- multiple TICCs can be connected to yield 4, 6, 8, or more synchronized > channels, though we haven't tested this capability yet.) > > I've attached a picture of the TICC prototype as well as an ADEV plot of a > 17+ day run of multiple measurements taken by two TICCs, and also showing the > TICC noise floor. The good news behind that plot is that there are more than > 6 million data points behind these results, and there was not a single glitch > or significant outlier among them. > > There's more information available at http://febo.com/pages/TICC > > The software is open source (BSD license) and is available at > https://github.com/TAPR/TICC -- the current version seems be reliable but > there are still features to add and a *lot* of cleanup to do; it's currently > ugly and very much a work in process. > > As always, I'll be making the TICC available through TAPR. We're still > finalizing details, but we expect the price to be less than $200 for a > turn-key system: TICC mounted on an Arduino with software loaded and tested > for basic functionality. We hope to ship the TICC by February. > > I'll post a note in a week or two with final price and ordering information. > As a heads up, we will probably offer a small discount for pre-orders. TAPR > is a shoestring non-profit group and the up-front cost to manufacture this > unit will frankly be a challenge for us. Getting pre-orders will help our > cash flow significantly, so we ask you to keep that in mind. > > John > > <TICC_rev_c_photo_small.jpg><ticc_rev_c-perf_test_adev.png>_______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
