Define better. I am passing the output at a different frequency through a
Wentzel oscillator to "clean it up". That gets rid of farther out spurs, so
I chose settings that pushed spurs as far as possible. I'm not sure you can
determine what is best for your application without measuring the output
If you have some volume, consider Small Batch Assembly:
https://www.smallbatchassembly.com/
They are not as cheap as the Chinese suppliers, but you can provide
your own components, and it is run by a very helpful gentleman in the
Washington DC area. I got the bare boards from OshPark and you can
Note that many (maybe all) TCXOs exhibit a hysteresis effect when the
temperature cycles. The stability reported on the datasheets is only
tested with a temperature change in one direction. Cycling temperature
up and down will result in more variation. I've seen two or three
times the datasheet
There is lots of work in this area. Search "accelerated life testing
electronics" and you will find lots of information at various levels.
These guys have the PhD version, but you have to pay to join or be an
academic for access.
https://calce.umd.edu/
I've worked with this in the Aviation
Similar sense of humor. See if the attachment comes through.
Regards,
Mark
On Sat, Jun 20, 2020 at 10:48 AM Bob Fleming wrote:
>
> Divide by 81 has resulted in a great conversation but I could not help but
> notice a potential attempt at humor.
> 10Mhz divided by 81 is 123456.7901 which I
I believe Wenzel makes custom parts for various customers and won't divulge
any info unless you are that customer. I did email them and they were
willing to provide me a datasheet of a similar standard part. You could try
asking that. I have a 500-16423A and they sent a datasheet for a 501-14057
If you are concerned about phase noise, choose your regulator carefully.
Even many linear regulators are noisy enough to degrade phase noise. There
are lots of low noise regulators to choose from.
Regards,
Mark
On Thu, Jan 30, 2020, 1:18 PM Tobias Pluess wrote:
> Hi guys
> I have almost
I created a temperature test setup for my TCXOs. Relay control did not last
long because the relay was operating once a second or so and the Peltier
uses a lot of current. The relay contacts welded in a few hours. Luckily I
was watching when it happened. A PID controller running H bridges works a
; section of 2/0 DLO cable, with a two bolt telco lug
> at each end. It failed at ~2200 ft/lbs, the wire itself broke strand by
> strand.
>
> Second test involved sawing the crimp across the barrel and looking for
> voids. Using factory lugs and die, no voids were visible at 25X
> magn
,
and eliminate failures that they have experienced.
Regards,
Mark
W7MLG
On Sun, Oct 6, 2019 at 9:01 AM jimlux wrote:
> On 10/5/19 7:11 PM, Mark Goldberg wrote:
>
> >
> > Building codes are published by the NFPA. They allow you to sign up and
> > view them online. You
It is even more difficult. I bought some cables from a company because I
did not have a crimper for 4/0. I was not impressed. My crimps were much
better.
I don't have a specific recommendation, but you should get a feel from them
that they understand the standards. Places that do work for
On Sat, Oct 5, 2019 at 6:03 PM Hal Murray wrote:
>
> Do the people who maintain the rules occasionally look around to see if a
> better way has been developed?
>
IPC, the Association Connecting Electronics Industries publishes a large
variety of standards that describe how to assemble
I am purchasing TCXOs from a reputable supplier and building boards to
install in Ham radios. Every one is indeed different. They also exhibit
hysteresis, sometimes very strong, more than the variation with
temperature. They test in one direction and meet the .25 ppm variation spec
over temp, but
That is the dirty little secret of crystals. Manufacturers will test the
temperature response in one direction, but if you heat and then cool
crystals and measure the frequency, they do exhibit significant hysteresis.
I've not been able to get a supplier of TCXOs for me to characterize this
as I
so outside. Maybe that's a
> solution? I didn't think about this because all other GPDSO locks just
> fine.
>
> ---
> (Mr.) Taka Kamiya
> I'm stuck in a wormhole Hello, worms!
>
>
> On Wednesday, April 10, 2019, 1:30:42 AM E
What kind of antenna and where is it located? I have a trueposition and it
seems to need a higher gain antenna than my other gpsdo, a modern Bodnar. I
put it outside with an amplified splitter and it works well.
When using another antenna or this one on the windowsill, it went into
holdover
You can't go wrong with a Fluke, although they are not cheap. I have one
Fluke 115 that I actually get calibrated every year. I also have a variety
of cheapies from Home Depot / Frys Electronics / Amazon and can't even tell
you what the brands are. They work too and all seem to agree. It depends
On Wed, Mar 13, 2019 at 9:02 AM jimlux wrote:
> If I go out and buy 100 TCXOs with a spec of, say, 50 ppm, what does the
> distribution of the initial frequencies (and, I suppose, the frequencies
> after aging) look like.
>
>
If you are buying 1000, you probably will get the manufacturer to test
On Wed, Jan 30, 2019 at 1:00 PM Bob kb8tq wrote:
> Hi
>
> The thing I’m not quite understanding here - why in the world use an
> antenna that needs
> a ground plane when you can get one that does not need an external ground
> plane?
>
>
What can I say, that antenna was $5.45, locally picked up
Put a "Bird Feeder" on the side of the house.
Even only seeing less than 1/2 the sky, this is doing OK with just a
TruePosition L1 GPS, always 7-8 sats. I have room for two antennas on the
ground plane, only have one and am using an HP 58515A active splitter.
Hopefully the attachment comes
On Fri, Jan 25, 2019 at 3:05 PM Bernd Neubig wrote:
> Hi all,
>
> Sorry the URL given below was broken into two lines. In its total it must
> read
>
> https://www.axtal.com/English/Products/OscillatorModules/PhaseLockedOscillat
> orModules/
>
On Thu, Jan 24, 2019 at 2:01 PM jimlux wrote:
>
> At least one version is available from Mouser for $85.
>
> And I'm sure if I wanted to order one with something slightly different,
> Vectron would do it.
>
>
>
>From my previous experience (asking for a custom frequency TCXO) Vectron's
business
On Wed, Jan 23, 2019 at 11:00 PM Richard (Rick) Karlquist <
rich...@karlquist.com> wrote:
>
>
> The 10811 brings out oven and oscillator power separately. However,
> if you don't power up the oven, the crystal will be way off frequency
> so your idea is a non-starter.
>
>
Not to go too far off
I'm using a Wenzel Phase Lock Oscillator as a "clean up" oscillator for my
Bodnar GPSDO. I lack the capability to measure if it really can do as they
advertise, but the 1 kHz away phase noise is claimed to be in the -170
dBc/Hz range. The ADC noise floor keeps me from measuring anywhere near
that
On Sun, Jan 20, 2019 at 5:10 PM Magnus Danielson wrote:
> Hi Mark,
>
> I have not seen anyone comment on this post yet.
>
> It's an interesting approach and in general, this is one of the ways we
> can expect that frequency/stability measurements to be done these days,
> by sampling the RF and
I believe I finally have my frequency measurement process refined and have
described it here:
https://drive.google.com/open?id=1luVumTygkvfnDsZvGZGSsJA75IwMKmJ8
Comments, corrections and criticism are welcome.
Regards,
Mark
W7MLG
___
time-nuts
On Tue, Jan 1, 2019 at 4:40 PM Jeff Blaine wrote:
> Take a look at the plots at the bottom of this page.
>
> http://hpmemoryproject.org/technics/bench/3048/hp_sources_02.htm
>
> Note the 8642b vs the 3325B. The '42b has much lower ultimate noise far
> out but see how decent the 3325B is in
I have done a study of how good it needs to be on my website:
https://sites.google.com/site/markstcxomeasurements/
Regards,
Mark
On Tue, Jan 1, 2019 at 2:34 PM Artek Manuals
wrote:
> The question that remains begging here from the original post (maybe off
> topic ?) is how low a phase noise
I don't know about the 3325B but the limited specs available don't give me
hope. They state -60dBc for a 30 kHz band around the carrier, excluding +/-
1 Hz about the carrier with option 001, but don't state how that noise is
distributed. Leo Bodnar's GPSDOs do provide good enough phase noise
As I have posted before, I am trying to use an SDR to make peak frequency
measurements at intervals using Spectrum Lab software to control the SDR
and record the data.I don't have the full info about what algorithms are
used to capture the peak frequency and was trying to look into various
methods
ing ADEV.
>
> Bob
>
> > On Dec 3, 2018, at 11:21 AM, Mark Goldberg
> wrote:
> >
> > I have looked at it multiple times and so far cannot see a discrepancy.
> The
> > ration of the ADEVs for the two sample rates is very close to 2 for a
> wide
> > ran
> of the
> data. I think you may want to look at the way you are doing ADEV.
>
> Bob
>
> > On Dec 3, 2018, at 12:30 AM, Mark Goldberg
> wrote:
> >
> > I ran them again today and the results are almost identical. The slower
> > sample rate still shows a lowe
ng enough. Most designs
> take days (if not weeks) to get to their ultimate stability.
>
> Bob
>
> > On Dec 2, 2018, at 11:16 AM, Mark Goldberg
> wrote:
> >
> > I broke down and drilled a couple holes in the wall and moved the
> antennas
> > for both GPSDOs
On Fri, Nov 30, 2018 at 8:56 AM Attila Kinali wrote:
> On Thu, 29 Nov 2018 21:22:44 -0700
> Mark Goldberg wrote:
>
> > How much could I expect ADEV to improve if I move the antenna to a better
> > location with clear view of the sky? The things I am testing need to be
>
On Mon, Oct 29, 2018 at 8:25 AM Dr. David Kirkby <
drkir...@kirkbymicrowave.co.uk> wrote:
>
>
> I have a 100 MHz scope, and can borrow a 300 MHz scope, but I don't have
> anything really fast.
>
> I have a VNA which can make measurements of phase difference down to 300
> kHz, but don't trust
On Fri, Oct 26, 2018 at 11:27 AM ew via time-nuts
wrote:
> It is two layer and I added an amp with two transformer outputs.
> I am not going to get in to board selling or shipping to oldBert
>
>
Although it is not the cheapest, OSHPark will let you upload your board as
gerbers and share it with
I agree they likely won't provide a schematic and will want it back for
repair. If it is a proprietary design for someone, they may not even repair
it for you and certainly won't give you any info. I was at least able to
get a little info from Wenzel about a similar oscillator I was looking at
and
For a radio BFO you want something with low phase noise (low jitter). The
SI5351 is not designed for that, and it's jitter spec is 70 ps, which is
pretty noisy. It even has a spread spectrum mode that would be even worse.
They do have other parts designed for low jitter (< 1ps). Leo Bodnar's
On Sat, Sep 1, 2018 at 3:49 AM, Dana Whitlow wrote:
>
> Question for Mark re metal foil under the antenna:
>
> What's the nature of the improvement? Between the large tilt angle and
the
> shape of the
> foil piece, I'd certainly not expect any material improvement in the
> multi-path department.
On Fri, Aug 31, 2018 at 12:41 PM, Gerhard Hoffmann wrote:
>
>
>> So you can test your hold over behavior with aluminum foil (or your hand)
>> over your antenna
>>
>> OMG, I first read "with aluminium foil hat over your head"
>
Now, foil under the antenna on the other hand, big improvement!
It can be watched on the History Channel's website if you have a TV
provider that carries it and sign in.
Tom, you made an excellent scientific presentation in the middle of others
that were somewhat more "fanciful".
Regards,
Mark
On Fri, Aug 17, 2018 at 2:07 PM, Tom Van Baak wrote:
> Check
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