Re: [time-nuts] The home time-lab

The PFC power supply architecture I had in mind uses a flyback inverter to regulate the input rail voltage for the output dc-dc converter stage. The flyback stage peak current is modulated by a sinewave. A feedback loop adjusts the effective amplitude of this sinusoidal modulation to regulate

Re: [time-nuts] NCOCXO anyone?

> 24 bit DAC Which chip are you using? How many useful bits do you think you will get? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] The home time-lab

Years ago I knew exactly how Sola regulators worked. That has faded, but what remains is that the regulation was done by varying the saturation of the core. That's why there is a slot in the laminations. I find it hard to believe that a partially saturated core can produce zero harmonics. In any

Re: [time-nuts] The home time-lab

Are there some reference designs you can point to where this is a problem? Because all of the application notes and references designs I have checked so far have no requirements for input wave shape other than peak and to a lessor extent RMS voltage. The input power factor degrades with inputs

Re: [time-nuts] The home time-lab

That is interesting, since the Sola device has a to the line frequency tuned tank circuit in it, thus the output should not have to many higher harmonics and should look reasonable close to sinusoidal see here: http://www.rdrelectronics.com/russ/jun16/vs2.PDF 73 K6UHN Alex On 7/24/2016

Re: [time-nuts] Precision DACs (was: NCOCXO anyone?)

On Sat, 23 Jul 2016 20:36:28 +0200, you wrote: >On the other hand, a modern DACs like the AD5791 reaches full 20bit at 1Msps >(resp 1us settling time to 0.02% @10V step, or 1us to 1LSB @500 code step). >But using the AD5791 in a design isn't easy either. The dual voltage reference >that is

Re: [time-nuts] The home time-lab

The PFC stage needs a line frequency sinewave reference, if this is produced by attenuating the line input, then it may not function well with badly distorted line input waveforms (modified sine, square wave etc).Phase locking a sinewave to the line input may be a better approach. Bruce

Re: [time-nuts] The home time-lab

Hi David: Yes, the computer, monitor, and DSL modem, switch, answering machine were connected. I haven't remembered how to run the DSO in the short time the self test lasts. AC VRMS line= 117, AC VRMS UPS = 114. -- Have Fun, Brooke Clarke http://www.PRC68.com

[time-nuts] Venus838LPx-T opinions?

The closest thing to an official Lady Heather site if John Mile's ke5fx.com I also want to put it it up on Github when the code settles down some. The good Lady Heather doesn't accept donations of the monetary kind. Receivers not currently hoarded in her dungeon are appreciated.

Re: [time-nuts] The home time-lab

Hi Brooke, Thanks for that info.  I've got the important bits (PRS and GPSDOs) now hooked up to an APC Smart-UPS 700.  What will happen when it goes to battery power, I don't know.  I've been doing qualification testing on a new batch of GPSDOs, so I haven't had time to do any testing of power

Re: [time-nuts] The home time-lab

On Sun, 24 Jul 2016 14:45:02 -0700, you wrote: >Hi Bob: > >The Sola 500 VA transformer is specified to hole up the line voltage for 3 ms. > (but not a half cycle of the line >frequency). > >I've connected the Sola CVS transformer to the output of the APC RS1500 backup >UPS. (needed to replace

Re: [time-nuts] The home time-lab

Hi Bob: The Sola 500 VA transformer is specified to hole up the line voltage for 3 ms. (but not a half cycle of the line frequency). I've connected the Sola CVS transformer to the output of the APC RS1500 backup UPS. (needed to replace the 2 batteries in the main unit and probably within a

Re: [time-nuts] NCOCXO anyone?

Richard (Rick) Karlquist writes: > The last thing you want in an oven is a lot of > added thermal overhead, especially in a double oven > where you already fighting against running out of > temperature range. If you want to ovenize everything > but the kitchen sink, put it in it's

Re: [time-nuts] Venus838LPx-T opinions?

I have been running Heather on Ubuntu MATE 16-04 since Mark released it. Wonderful. Currently running or a R Pi 3B with lots of machine to spare! Cheers! Dave Mallery On Sun, Jul 24, 2016 at 12:03 PM, Mark Sims wrote: > I am the creator author of Lady Heather. The code

Re: [time-nuts] Venus838LPx-T opinions?

LOL! Thank so much for the history of how you got trapped... errr started in the Lady Heather software project. :) Questions still remain: 1) What is the link to the "official" Lady Heather site? 2) How/where can we shoot a donation to say "Thanks!"? 73, __ Clay Autery,

[time-nuts] Venus838LPx-T opinions?

I am the creator author of Lady Heather. The code in Lady Heather started out from a program that I wrote to control Magellan GPS receivers (like the OEM-5000) back in days of the first Gulf War... it ran under DOS as a text mode only program. When TAPR did their group buy for Trimble

Re: [time-nuts] NCOCXO anyone?

On 7/24/2016 6:44 AM, James Flynn wrote: Hal Murray writes: Has anybody put the DAC and all of the analog stuff inside the oven? Seems like an obvious idea so somebody has probably patented it. I am using a 5 MHz custom built design which has everything inside the outer oven

Re: [time-nuts] Venus838LPx-T opinions?

AWESOME!!! :) Added to project list!!! Mark, what's your official link to Lady Heather and how do we donate to the cause? 73, __ Clay Autery, KY5G MONTAC Enterprises (318) 518-1389 On 7/24/2016 12:23 AM, Mark Sims wrote: > Lady Heather now works with Venus receivers

Re: [time-nuts] NCOCXO anyone?

Hal Murray writes: > That still leaves the temperature quirks of the DAC and amplifiers. > > Has anybody put the DAC and all of the analog stuff inside the oven? Seems > like an obvious idea so somebody has probably patented it. > I am using a 5 MHz custom built design which

Re: [time-nuts] Venus838LPx-T opinions?

Yo Mark! On Sun, 24 Jul 2016 05:23:54 + Mark Sims wrote: > Why somebody thought it was a good idea to not include that info in > the binary messages boggles the mind... I hate having my mind > boggled. For some reasaon they never seem to ask us before designing their

[time-nuts] Venus838LPx-T opinions?

Lady Heather now works with Venus receivers in mixed binary / NMEA mode. So now it can display the sky view data (via NMEA sentences) while running in Venus binary mode. I also added support for parsing the $PSTI NMEA sentence that contains the sawtooth correction info. Why somebody