Re: [time-nuts] WWVB Dephaser Question

Paul: The easiest way to convert a single sample into an I-Q representation is to have a two phase local oscillator. You multiply the incoming signal against the primary phase output of the oscillator for the I channel, and multiply the same sample against the 90 degree offset output for the Q

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

Hi, If I where able to do that with helping hands in a lab and get a few crystals that actually work and produce oscillating oscillators, even if the frequency and Q isn't anything near stellar, that would still have value. It would be gained experience, but not really anyway near production

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

On 10/24/20 3:14 PM, Bob kb8tq wrote: After it’s sealed up (and possibly processed a bit after seal) you test it to see how you did. Some number will be ok, the rest head into the trash. The good ones go into oscillators. Is that 5% or is that 80% … depends on what you are after …. Bob

Re: [time-nuts] WWVB Dephaser Question

On 10/24/20 3:53 PM, paul swed wrote: Antenna and filtering are not a problem for me. I use the 10' X 10' square loop and about 800' of wire with a cap to resonate at 60 KHz and then a preamp really to drive 140' of coax. Currently using a modified KD2BD receiver frontend but using a 350 Hz xtal

Re: [time-nuts] Query about insulated coax panel connectors?

If panel and connector sizes permit a small single hole panel mount connector can be insulated with a fiber shoulder washer and a flat fiber washer. https://www.keyelco.com/category.cfm/Shoulder-Washers-Bushings/Fibre-Shoulder-Washers/id/813

Re: [time-nuts] WWVB Dephaser Question

Antenna and filtering are not a problem for me. I use the 10' X 10' square loop and about 800' of wire with a cap to resonate at 60 KHz and then a preamp really to drive 140' of coax. Currently using a modified KD2BD receiver frontend but using a 350 Hz xtal filter. Yes indeed that hamfest find

Re: [time-nuts] Query about insulated coax panel connectors?

Hi Mini-circuits will sell you the transformers already in a box. Needless to say, they do charge a bit for that. Occasionally, you can find them on eBay for a more rational price. If you are going the DIY route, incorporating a couple of common mode chokes on both sides of the transformer is

Re: [time-nuts] Query about insulated coax panel connectors?

Jim A couple of other suggestions. A 1:1 Mini circuits transformer external to the unit They are quite small and offer electrical isolation also. Use a small pomona box etc. Another possibility is the typical RCA phono jack and plug. They come in insulated models. Understanding its not 50 ohms but

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

Hi The gotcha is that if you want to *use* what’s in that book ( I have a copy and went to the course back in the 1970’s) the first step is to grab a chunk of quartz. Next you head over to your X-ray setup and work out what you have. After that you go over to the saw and chop some raw blanks.

Re: [time-nuts] Query about insulated coax panel connectors?

Dear Jim These, in conjunction with some M6 nylon washers, work OK for isolating an SMA bulkhead feedthrough from the case: https://www.minikits.com.au/components/hardware/washers/Metric-M6-Washers (the nylon shoulder washers down the bottom) The connector will rotate though if you try to torque

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

Try Dave Henderson at Artek Manuals. He does the best job scanning things. DaveD > On Oct 24, 2020, at 15:12, Mike Feher wrote: > > This did not make it the first time because I had attached photos that were > too large. I have an original copy of Don Firth's publication on "Quartz > crystal

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

On Fri, Oct 23, 2020 at 10:55 PM Wes wrote: > Not exactly the same book but the same author: > > "Introduction to quartz crystal unit design" There seems to be a copy in the > UK I see several copies of this in the $20 range on bookfinder.com, click "view all matches combined" at the link

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

It may not be current, but IMHO it would not be a waste of time read it. If one wants to extend the knowledge gained from reading the the book to include more current theory I am sure that additional resources could be found. DaveD > On Oct 24, 2020, at 07:43, Attila Kinali wrote: > > On

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

Hi > On Oct 24, 2020, at 7:43 AM, Attila Kinali wrote: > > On Fri, 23 Oct 2020 19:32:16 -0400 > Bob kb8tq wrote: > >> This book is an introduction to designing AT cut resonators. It came out >> before the SC existed. It’s very much a “starter” book on the subject. He >> would do a 1 to 3 day

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

There's a copy of Introduction to Quartz Crystal Unit Design by Virgil E Bottom for sale on thriftbooks.com but it's available to "borrow" on Archive.org and there are several copies of Theory and Design listed in various US university libraries on worldcat.org perhaps a friendly faculty member or

Re: [time-nuts] SMPS or conventional?

From: ed breya To: mailto:time-nuts@lists.febo.com Subject: Re: [time-nuts] SMPS or conventional? "Regarding TEC life, ..." A really good reference to TECs, especially factors affecting lifetime is here - https://tetech.com/faqs/ John

[time-nuts] Query about insulated coax panel connectors?

Time-nuts: Having recently run into major ground loop noise issues, I have begun reworking some of my homemade pieces of equipment using insulated coax connectors. My goal is to have one ground connection only in the cases, and that is at the power entry point, either a power cord or the outer

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

This did not make it the first time because I had attached photos that were too large. I have an original copy of Don Firth's publication on "Quartz crystal oscillator circuits design handbook". This was developed under a government contract by the US Army. Don was a friend while I was at

Re: [time-nuts] Quantum Time Dilation

A reasonably simple description of this paper was released by Scientific American today: Quantum Time Twist Offers a Way to Create Schrödinger’s Clock https://www.scientificamerican.com/article/quantum-time-twist-offers-a-way-to-create-schroedingers-clock/ The Schrödinger’s Cat thought

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

Hi >From what I can see, all are essentially editions of the same book, updated as he continued to do his classes. Bob > On Oct 23, 2020, at 9:50 PM, Wes wrote: > > Attila, > > Amazon says (Out of print): > > * Publisher : McMurray Press; 1st Edition (January 1, 1968) > * Language: :

[time-nuts] 5065A Rb Cavity RX - SRD Repair

Thanks for the picture. The small coax link cable is even more brown  than the one i my cavity  I did realize that it should be possible to test the diode  using a 20k/V resistance meter. There has been no more "hick-ups"  and what the cause was is unknown, but many repair sessionscan

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

On 10/23/20 6:50 PM, Wes wrote: Attila, Amazon says (Out of print):  * Publisher : McMurray Press; 1st Edition (January 1, 1968)  * Language: : English  * ASIN : B0007H97C8 Not exactly the same book but the same author: "Introduction to quartz crystal unit design"  There seems to be a

Re: [time-nuts] Looking for "The Theory and Design of Quartz Crystal Units" by V.Bottom

On Fri, 23 Oct 2020 19:32:16 -0400 Bob kb8tq wrote: > This book is an introduction to designing AT cut resonators. It came out > before the SC existed. It’s very much a “starter” book on the subject. He > would do a 1 to 3 day training session and the book was a giveaway as > part of those

Re: [time-nuts] WWVB Dephaser Question

Hello Time Nuts and Paul, Glad to hear you're making progress - of course, as Chris Howard mentioned earlier - it's all based on this as a starting point: https://github.com/DD4WH/Teensy-DCF77 and Chris' work is here: https://github.com/chris-elfpen/Teensy4WWVBsdr Those sites are good to look

Re: [time-nuts] WWVB Dephaser Question

Hello Time Nuts and Paul Again, Paul - Have you thought about adding a 2nd audio board for the orthogonal antenna?: https://www.pjrc.com/store/teensy3_audio.html I think adding a 2nd audio board could work for this possibly - of course with the correct antenna set up. Note the setup they have