[time-nuts] new tdc from Texas
Sparkfun is selling a board (around $15) based on the STM VL6180 chip that measures distance based upon time-of-flight of pulses from an on chip (or at least in-package) VCSEL IR laser. Claims to have a range of 0 .. maybe 30 cm. Unfortunately it doesn't look like you can directly access the time interval measurement portion of the chip. Do you know if they have an IR pulse front end which would be more interesting than the ultrasonic front end? ___ 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.
Re: [time-nuts] Trimble Thunderbolt NMEA ?
Is the code in C? If so I bet it would run on some development board. No need to make custom PCBs. On Tue, Mar 3, 2015 at 5:00 AM, Didier Juges wrote: > Tim, > > It shouldn't be too hard to modify the code for my Thunderbolt monitor to > make it into a TSIP->NMEA converter. The last version of the kit has a uC > with two serial ports. I m out of the kits at the moment but I have a few > spare boards left over. > -- Chris Albertson Redondo Beach, California ___ 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.
Re: [time-nuts] Recording mains frequency/phase [WAS: NoGPSsatellites]
Hi Tom and list! Thank you for the responses. This has been very educational. On 3/2/2015 2:55 AM, Tom Van Baak wrote: 1) The PC program that reads the serial port can toss lines it doesn't want. I'll publicly expose my silliness here - I never thought about the program end of things. I was simply thinking something like an old terminal program with logging turned on. Last night in a sleepless moment I got to thinking: this seems like a great use of a Raspberry Pi. It can parse the serial, save the data to a file, start a new file each day, each week, etc... Plus, I can set it up to be a network file location so I can analyze the files elsewhere easily. I'm going to pursue this. I've got two already - one is a GPS-based NTP server...the other is an ADS-B receiver / reporter. 3) The other solution that I often use is a version of the picPET (pP19) that deliberately takes 990 ms to output the timestamp (events are counted in h/w). This would be perfect. While discarding the unwanted data should not be hard...not having to do it at all is easier. ;) Yes, see code above. Same logic in any language, but probably one line of code in awk or perl or python. I'll probably end up learning some python in doing the serial logger above. It seems to be a language of choice for the Pi. If you do it up-front, like a pre-scaler, you have to worry about signal quality to avoid off-by-one glitches. You'll get lots of suggestions here on the mailing list and on the web about how to best detect zero-crossings. The circuits get pretty complex. It may surprise you that I don't do any of that. I wasn't aware of this, so its very good to know. :) The beauty of timestamping (instead of traditional counting) is that signal conditioning is much less important. I put raw 5 VAC into the PIC pin via a 10k resistor. That's it. Any "conditioning" can be done in software. It is a lot simpler too. Simple is always good in my book. (mostly because I'm too stupid to do much that is complex!) thanks much and 73, ben, kd5byb ___ 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.
Re: [time-nuts] new tdc from Texas
Hi Angus: Do you know if they have an IR pulse front end which would be more interesting than the ultrasonic front end? Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html Angus wrote: In case anyone is interested, the full data sheet is on the TI site now, although I didn't see any actual IC's yet other than the ones in the eval boards. Angus. On Tue, 17 Feb 2015 21:24:08 -0200, you wrote: Initial datasheet: http://www.ti.com/lit/ds/symlink/tdc7200.pdf EVM: http://www.ti.com/tool/tdc1000-tdc7200evm Seems good... what do you think? Daniel ___ 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. ___ 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.
Re: [time-nuts] new tdc from Texas
In case anyone is interested, the full data sheet is on the TI site now, although I didn't see any actual IC's yet other than the ones in the eval boards. Angus. On Tue, 17 Feb 2015 21:24:08 -0200, you wrote: > >Initial datasheet: > >http://www.ti.com/lit/ds/symlink/tdc7200.pdf > >EVM: > >http://www.ti.com/tool/tdc1000-tdc7200evm > >Seems good... what do you think? > >Daniel >___ >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.
Re: [time-nuts] Trimble Thunderbolt NMEA ?
On Mon, Mar 2, 2015 at 5:06 PM, Tim wrote: > On 3/03/2015 4:33 AM, Didier Juges wrote: > >> Tim, >> >> NMEA is normally used for navigation. It would seem unlikely that anyone >> would want to use a Thunderbolt for navigation. Can you elaborate on what >> you are trying yo do? >> >> >> Hi Didier, > > I' building a multi frequency beacon based on QRP-labs U3 beacon kit. It > has the ability to discipline its oscillator with a PPS input and, using > NMEA input, set and maintain time and location for exact control of WSPR > and OPERA modes of operation. > > As it currently only accepts NMEA input I was wondering there was a way to > get NMEA out of a thunderbolt. I've lodged an RFE with the developer to add > TSIP support to the U3, but I don't think that's going to happen anytime > soon. > > I'd rather use the Thunderbolt as the time and PPS source since its way > more accurate than the LEA-M8FGPS module that optionally comes with the kit. > This may be a case where duplication of hardware might be the simplest solution. Navigation receivers that output 1pps and NMEA data are a dime-a-dozen now, under $50. Go look at what is available from the likes of SparkFun or Adafruit. For disciplining the clock in in the computers running your WSPR and OPERA software even the cheapest receivers greatly exceed the required timing accuracy. (NTP across the net is sufficient for these applications.) What I am doing is using a BeagleBone Black and a Jackson Labs LTE-lite receiver as my household stratum-1 NTP server and backup 10MHz and 1pps reference. In the same enclosure I am mounting my Trimble Thunderbolt to use as my primary 10MHz and 1pps reference. Fan-out of these signals is accomplished using the TAPR TADD-1 and TADD-3 distribution modules. All of this is easy to accomplish with a minimum of hardware and software hacking. I am mounting everything in a 2U rack case into which I plan to incorporate a battery backup. By time-nuts standards this is pretty mundane, but still represents a very credible level of performance from a ham-radio and general timing point-of-view. -- Brian Lloyd 706 Flightline Drive Spring Branch, TX 78070 br...@lloyd.aero +1.210.802-8FLY (1.210.802-8359) ___ 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.
Re: [time-nuts] Trimble Thunderbolt NMEA ?
Tim, It shouldn't be too hard to modify the code for my Thunderbolt monitor to make it into a TSIP->NMEA converter. The last version of the kit has a uC with two serial ports. I m out of the kits at the moment but I have a few spare boards left over. Don't have time to write the code at the moment, but I have released the source code for the kit. Didier KO4BB On March 2, 2015 5:06:21 PM CST, Tim wrote: >On 3/03/2015 4:33 AM, Didier Juges wrote: >> Tim, >> >> NMEA is normally used for navigation. It would seem unlikely that >anyone would want to use a Thunderbolt for navigation. Can you >elaborate on what you are trying yo do? >> >> >Hi Didier, > >I' building a multi frequency beacon based on QRP-labs U3 beacon kit. >It >has the ability to discipline its oscillator with a PPS input and, >using >NMEA input, set and maintain time and location for exact control of >WSPR >and OPERA modes of operation. > >As it currently only accepts NMEA input I was wondering there was a way > >to get NMEA out of a thunderbolt. I've lodged an RFE with the developer > >to add TSIP support to the U3, but I don't think that's going to happen > >anytime soon. > >I'd rather use the Thunderbolt as the time and PPS source since its way > >more accurate than the LEA-M8FGPS module that optionally comes with the >kit. > >I'd like to use the U3 as the basis of beacons all the way to 10GHz and > >the Thunderbolt is a superior device for locking such things and >supplying the base 10Mhz to lock the appropriate LO's. > >thanks > >Tim > >-- >VK2XAX :: QF56if23 :: BMARC :: WIA :: AMSATVK > >___ >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. -- Sent from my Motorola Droid Razr HD 4G LTE wireless tracker while I do other things. ___ 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.