Burt, who was this guy? Maybe I know him. Was he a ham?
I couldn't take all the stuff but might be interested in some of the smaller
items. Is there test equipment as well?
I don't have a truck; I live in the SFV so it could be worth my time to drive
over and cherry pick, if that's an option
There isn't a whole lot of justification for measuring power line frequency.
We are all synchronized (in the first world at least) and while there are phase
instabilities, it's seldom the frequency varies enough to overcome the noise.
As for voltage, it's much more steady than several years ago
Scott, it's a shame to trash those great counters. I gave away two of them a
while back; one is missing a decade counter so I'd be interested in replacing
that. The oven assembly is a great unit as well. Plug-ins are nice too,
especially the one that goes to 500 MHz.
Those counters were manu
You found the secret. There is no RF wiring to the crystal. The oscillator
frequency is determined elsewhere, with a free running multivibrator that is
approximately on the right frequency. All this talk about precision is
baloney; the circuit is stable enough to fool even the experts.
And i
So we leave the scientific considerations and delve into the philosophical
basis. Somewhere down the line, a standard has to be established, to which all
others can be compared. How good this standard is doesn't matter, as long as
it's stable. But how does one measure stability? Against wha
Someone has been selling one of these at a reasonably low price on ebay but I
don't know anyone who has used it.
Bob
On Saturday, November 18, 2017, 11:05:09 AM PST, Attila Kinali
wrote:
Hi,
I have a need for a GBIP adapter that I can use with Linux.
It shouldn't be too expensive, but
I built one, and later saw a simpler one. Very fast, very simple. I think my
total cost was a few cents.
Google TDR DIY pulser. One from an old magazine (Jim Williams) looks pretty
good, using collector breakdown of a 2N2369. The one I made used one IC and a
few resistors.
Bob
On Tue
Well 5 cycles per second is more than accurate enough. That translates to a
150 Hz error at 30 MHz, definitely negligible for the uses of all these gear.
There was no official Time Nuts group at the time, although many of us had the
spirit. Yet the capability of the BC-221 far exceeded its sp
's much
better than trying to null two carriers. Even better if you use stereo
headphones with the left on one radio and the right on the other.
Bob
From: "jmfra...@cox.net"
To: Discussion of precise time and frequency measurement ;
Bob Albert
Sent: Sunday, Febr
First you need a standard, a crystal oscillator. If you want serious
precision, you'd have one in an oven. Zero beat that with WWV. Then make a
very stable VFO and calibrate the harmonics against the crystal. Assume linear
calibration on the VFO between check points.
The military LM and BC-2
grees
or zero degrees must be calibrated to find the ratio and thus the sine or
cosine of the phase difference.
And while I never asked why we want to do this, I am reserving that question
for later.
Bob
On Saturday, October 1, 2016 5:17 PM, Bob Stewart wrote:
Hi Bob Albert,
I
I am having trouble following this thread. I assume we are trying to measure
phase noise, but of course the result includes the noise of the local
oscillator(s). Isn't the 3456A a voltmeter? I have one of those. In AC mode
it has a bandwidth of more than 100 kHz and measures true rms.
Someo
Better stock up on 60W bulbs. They are becoming outlawed.
(Only kidding, a resistor works as well.)
Also, a foam drink cooler will give a more stable temperature. You can make it
leak a bit of heat to get the thermostat to cycle. The hard part is the
thermostat; they aren't cheap - even the lo
works really well to about 575MHz.
Traces can get noisy after about 575MHz.
Remember these VNAs are only as good as the calibration kit you use with them!
Orin.
On Sat, Aug 20, 2016 at 9:46 PM, Bob Albert via time-nuts
wrote:
I was interested in this, but my needs are mostly below 100 MHz.
I was interested in this, but my needs are mostly below 100 MHz. I wonder what
could be done similarly for this lower range...
Bob
On Saturday, August 20, 2016 8:54 PM, Richard (Rick) Karlquist
wrote:
Another great posting, Attila.
When I was with Agilent, we looked at all kinds of
---
AE6RV.com
GFS GPSDO list:
groups.yahoo.com/neo/groups/GFS-GPSDOs/info
From: Bob Albert via time-nuts
To: Discussion of precise time and frequency measurement
Sent: Thursday, August 18, 2016 8:49 PM
Subject: Re: [time-nuts] Subject: Re: Working with SMT parts (Bob Al
to find.
It works so much better than lead free.
-Chuck Harris
Bob Albert via time-nuts wrote:
> Well I have found some Chinese sources of 42 - 50 grams on ebay for around
> $3. Is
> this the right stuff? The brand is Mechanics.
>
> Bob
___
fine powder that
it has a huge surface area to oxidize. As long as you keep
the air off, and refrigerate the paste, it seems to go forever.
Oh, and I only use tin/lead paste, not the RoHS stuff.
-Chuck Harris
Steve Wiseman wrote:
> On 18 August 2016 at 07:07, Bob Albert via time-nuts
>
Well I have found some Chinese sources of 42 - 50 grams on ebay for around $3.
Is this the right stuff? The brand is Mechanics.
Bob
On Thursday, August 18, 2016 12:11 PM, Bob Albert
wrote:
So where do you get this expired paste? I have tried a few searches but no
luck.
Bob
Ah Steve, that's good info! Now where does one buy expired solder paste? And
what's the proper name for it - solder paste searches mostly come up with just
flux.
Bob
On Thursday, August 18, 2016 2:25 AM, Steve Wiseman
wrote:
On 18 August 2016 at 07:07, Bob Albert via
ast logic and has been used in many Time-Nuts
application like cheap zero-cross detectors using the AC04.
https://www.youtube.com/watch?v=9cP6w2odGUc
Regards --Jim Stone
Bob Albert wrote:
Well I got my adapter boards from China and managed to build my first SMT
project, a square wave generator
Well I got my adapter boards from China and managed to build my first SMT
project, a square wave generator for TDR use. And it works! The IC seems to
run hot so I used my IR temperature measurement device and it checks out at
about 37C, acceptable. I can now drive a square wave at about 3 kHz
I appreciate the advantage of stereo, which gives information as to how close
the tools are to the work. That could be important. However, it's not
necessary once you adapt to your tools.
Bob
On Friday, August 12, 2016 10:04 PM, Chuck Harris
wrote:
A fairly large part of the popula
, 2016 at 10:24 AM, Bob Albert via time-nuts
wrote:
> What are the important parameters regarding purchase of a stereo microscope?
> I see some on ebay for around $50; are those good?
> Bob
>
>
> On Thursday, August 11, 2016 10:00 AM, Didier Juges
>wrote:
>
>
What are the important parameters regarding purchase of a stereo microscope? I
see some on ebay for around $50; are those good?
Bob
On Thursday, August 11, 2016 10:00 AM, Didier Juges
wrote:
I concur. I have been using ExpressPCB extensively over the last 2 years
with great satisfact
Thanks David. I have ordered some from ebay, very cheap.
5pcs SO/SOP/SOIC/SSOP/TSSOP/MSOP14 to DIP 14 Adapter PCB Board Converter MA
| |
| | | | | | | |
| 5pcs SO/SOP/SOIC/SSOP/TSSOP/MSOP14 to DIP 14 Ad...US $1.32 New other (see
details) in Business & Industrial, Electrical & Test
Yes, a board with the required footprint would be the way to go. Where does
one find that?
On Tuesday, August 9, 2016 12:00 AM, David wrote:
Richard mentioned the SMD to leaded adapters which work well.
Another way which is more suitable for Manhattan or dead bug type
construction is
n dip.
73, Dick, W1KSZ
-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Albert via
time-nuts
Sent: Monday, August 08, 2016 8:37 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Safely getting the electrical l
Your comments on layout made me think again of how to implement these projects.
How do you use a 14 pin SMD IC? I could try to connect it with flying leads
but I'd like something better. Is there some kind of socket for these devices?
Or a generic board to receive such things?
Bob
On
match, the harder it
is to make the measurement, which is why I suggest finding a frequency range
far from the design of the termination equipment.
Your TDR should work also.
Bob
On Monday, August 8, 2016 1:23 PM, Bob Albert via time-nuts
wrote:
I host a group called something like H
I host a group called something like HF Antennas. There I posted a link to an
article on how to measure coaxial cable. The easiest way is with a spectrum
analyzer and a tracking generator.
You connect the generator to the analyzer through a Tee that goes to the
unknown coax. You will see a gr
Mitch, nice story! I can certainly vouch for its ring of truth, as I
experience the same thing on CW. I can often identify a station by the style,
speed, sound, or other characteristics. I can tell a bug from a straight key
from a keyer a lot of the time. And we won't talk about frequency dr
onday, March 28, 2016 7:20 AM, Bob Albert via time-nuts
wrote:
Dennis, that looks interesting but it seems to be a complete counter. I
wonder if I could cannibalize it to get the important input circuitry adapted
to my counter.
Maybe some info on it is available; I'll take a look.
Bob
4.html
>
> Will only divide by 8, it still goes higher than your counter. The eval board
> is a bit over $200. One piece of the Ic is < $12.
>
> Bob
>
>
>> On Mar 27, 2016, at 3:45 PM, Bob Albert via time-nuts
>> wrote:
>>
>> Does anyone know of
Does anyone know of an inexpensive prescaler for a counter that goes beyond 2
GHz? I would actually like to find a kit but everything seems a bit pricy. I
currently have capability of 500 MHz and that will stretch to about 700 with
care. So a divide by 10 would be ideal.
I think there is an Aeroflex or IFR yahoo group. But it doesn't see much
activity.
I own an IFR spectrum analyzer and would like to connect with others who have
solved problems and found new uses, etc.
Bob
On Tuesday, February 9, 2016 1:02 PM, Clint Jay wrote:
I've acquired from eBay
Well it seems to me to have too high a price. It could be useful; if I had one
I'd use it as a master oscillator for my HP counter. My ham transceiver is
very accurate so I don't need to improve on it.
If it were around $50 I would be very interested.
Bob K6DDX
On Sunday, October 18, 2
You can't use the square wave? You could put in a resonant circuit that will
select the fundamental but other issues arise, such as phase noise and harmonic
content. How much harmonic content can you tolerate?
There is a host of ways to do this job but much depends on your requirements.
Bob K6DD
you might like. Unless
you can count on the source to
be stable to << 10 ppm, stretching the points out to a full day apart probably
is not a good idea.
Lots of fun !!
Bob
> On Jul 1, 2015, at 6:47 PM, Bob Albert via time-nuts
> wrote:
>
> Okay that makes some sense. I will
t is closer to
being correct but I suspect the counter is closer.
Bob
On Wednesday, July 1, 2015 3:36 PM, Bob Albert wrote:
So I can measure the time interval, which should be one second. If I measure
10 intervals, my resolution would be 1 part in 10 million. I think I can set
the
So I can measure the time interval, which should be one second. If I measure
10 intervals, my resolution would be 1 part in 10 million. I think I can set
the master oscillator closer than that with beating against WWV. So maybe
buying a 1 pps source won't improve anything for me.
On W
I am missing something here. How does one use a 1 PPS signal? I see how I can
use a 1 MHz or 10 MHz for a time standard but the 1 PPS usage eludes me.
Unless the pulse is extremely sharp, a minor uncertainty in the shape or
amplitude will have profound effects on the timing.
I use an HP 5328A
Why not use a T connector to patch the 10 MHz to two places at once?
Bob
On Friday, April 24, 2015 5:06 PM, d0ct0r wrote:
Hello,
The input: HP 5386A which I would like to calibrate, Well warmed Tremble
Thunderbolt (1PPS only), 10 Mhz Datum OCXO (unknown accuracy), Rigol
1101E O
>From your comments, it seems that finding a voltmeter board to add to my 5328A
>isn't worth the trouble. I have been looking for one even though I have
>plenty of voltmeters. I assume the option allows measurement of the signal
>inputs but still probably isn't worth all the agony of changing
5V into 50 Ohms means 100 mA. Perhaps you need a medium power transistor
amplifier or opamp.
Bob
On Wednesday, March 4, 2015 6:09 AM, Martyn Smith
wrote:
Hello,
A quick question.
My output driver for a simple amplifier.
I use three gates (in parallel with resistors) from a 74AC
A TCXO does not keep a constant temperature. But an OCXO does. The TCXO
compensates for the temperature effect, while the OCXO holds the temperature.
Bob
On Sunday, December 7, 2014 1:47 PM, Joseph Gray wrote:
http://www.romanblack.com/xoven.htm
Joe Gray
W5JG
On Sun, Dec 7, 201
I have tried to pick up the oscillator from my wristwatch and have been
unsuccessful.
I tried both magnetic and electric probes. Nothing.
Bob
On Friday, April 18, 2014 4:12 PM, Tom Van Baak wrote:
> When a quartz watch or clock is assembled, what method is used to get it as
> accurate as
Yes, magnetic fields mess up mechanical watches. My dad was a watchmaker and
found the need to demagnetize all the watches he worked on. The hairspring was
the most sensitive part, and the coils would stick together if magnetized, and
the watch would run very fast.
Bob
On Thursday, April 1
I recently discovered that the 'square' wave from the oscillator was not
looking right.
I thought things were awry until I terminated the coax from the oscillator to
the 'scope. Then it looked good.
What probe are you using? If you are connecting from the oscillator to the
'scope via a piec
ur. (Both units have 24/7 ovens.) The
generator actually accounts for nearly all the drift. The counter is a
venerable HP 5245L with 500 MHz plugin.
Bob
On Sunday, March 2, 2014 10:33 AM, Tom Miller wrote:
- Original Message -
From: "Hal Murray"
To: "Bob Albert&
d signal?
Bob
On , Bob Albert wrote:
I'm not ready to delve into temperature measurement. But I thought
conventional wisdom is that most crystals are AT cut and an attempt at zero
average coefficient is made, causing a nonlinear characteristic. But perhaps
over a limited range it
ppb….
The other assumption above is that your existing reference is stable to much
better than 10 ppb. If it’s not, then you need both a reference and a way to
calibrate it. The GPSDO would give you both, since it’s got a 10 MHz OCXO built
into it.
Bob
On Mar 2, 2014, at 1:48 AM, Bob Alb
on
wrote:
On Sat, Mar 1, 2014 at 8:05 PM, Bob Albert wrote:
> Paul, as I said I just want to know how close my crystals are and be able to
> adjust them as well as they can be.
Don't say "as well as can be" that can get expensive and time
consuming. You need to use numbers
Paul, as I said I just want to know how close my crystals are and be able to
adjust them as well as they can be.
I probably will never go rubidium (note that I qualified that) but still
somewhere one has to decide where to set the frequency.
I did WWV at 20 MHz for a beat of somewhat slower th
All this is very interesting. However, my interest is frequency. In other
words, I want to know that my standard oscillators are as close to desired
frequency as possible, and how close that turns out to be.
Yes, the Internet gives me time of day as close as I care to know. I have an
'atomi
Steve,
Now that you have brought up this subject, do you know of any way to use these
LaCrosse clocks to calibrate frequency standards? It seems to me that since we
can buy a cheap device that receives and decodes the WWVB signal, it shouldn't
be a big step to use it as a basis for frequency m
What about converting an 'atomic clock' for this purpose?
Bob
On Friday, February 21, 2014 4:22 PM, Chris Albertson
wrote:
On Fri, Feb 21, 2014 at 10:37 AM, Paul wrote:
> Of course the products I referred to don't actually run ntpd and they're
> not disciplining the clock. Much like th
Oops yes I goofed, it's 500 MHz. 500 GHz is beyond state of the art I would
think.
So GPS satellites are NIST in miniature it seems. That's a lot of payload but
now I have to see how to gain access to it.
Bob
On Friday, February 21, 2014 11:17 AM, Florian Teply wrote:
Am Thu, 20 Feb 2
ike 50 ppm.
It's all in fun; I have no legitimate need for this accuracy.
Bob
On Friday, February 21, 2014 10:26 AM, Chris Albertson
wrote:
On Fri, Feb 21, 2014 at 9:47 AM, Bob Albert wrote:
> I looked on line and it seems that these receivers are available for about
> $150 and
purposes pretty much any of the solutions are very
good.
Regards
Paul.
On Fri, Feb 21, 2014 at 12:47 PM, Bob Albert wrote:
I looked on line and it seems that these receivers are available for about $150
and up. A little out of my price range right now but I'll keep my eyes open.
>
>
r the internet will
> work and if you already have an internet connection it's free. If you
> need a few nanoseconds then GPS is what you want.
>
> Using your beat with WWV as a benchmark. You were getting about one
> part in a million accuracy. It is VERY easy to do 10,000 times b
My TS-940S acts as though it receives okay at 60 kHz. Not great sensitivity
but it does receive.
Most HP GPS receivers are expensive ($400?). I was hoping to get some results
with what I have, although I'm willing to cobble up some circuitry.
I assume if I can receive the signal, I can figur
I am wondering if it's a tough road to get precise time and frequency.
I have a Kenwood TS-940S transceiver that can receive 60 kHz but I have never
heard anything I could guess would be WWVB, just a fair amount of noise. I did
calibrate against 20 MHz WWV so that the beat was one every severa
Check AC/DC coupling at the input. Make sure you are within the linear range
of input level. Look carefully at the signal to see if perhaps there are
glitches.
Measure other signals to determine if it's a counter problem or something not
noticed in the 1 pps signal.
Bob
On Sunday, Febru
Basically you just need an amplifier centered on 60 kHz.
On Friday, January 3, 2014 10:42 AM, Chuck Forsberg WA7KGX
wrote:
I'd like to see a WWVB generator that could output the 60 KHz WWVB signal
through a sound card for the benefit of hard of hearing "atomic" clocks
by Oregon Scientific
Jayson,
I chuckle because WWV is my favorite radio station also.
Why not tune it in on a good day and record the audio? Then you can digitize
it on the computer and have a .WAV file which you can play any time.
Trouble is, if you have recorded the announcements, you won't have the correct
ti
If the two frequencies are near one another you can measure the difference
frequency, which may or may not be helpful.
I know of no counter that can count two signals; that would require two
registers. Use two counters with synchronized time bases.
Bob
On Tuesday, October 22, 2013 9:15 PM
a few days you can have some
pretty good information.
Bob
On Sep 27, 2013, at 4:26 PM, Bob Albert wrote:
> I just did what I consider to be the best calibration possible without
> getting more equipment. I adjusted my generator to be within 0.25 Hz of 15
> MHz WWV. Then I matched m
s
possible between you and the transmitter.
Bob
On Sep 27, 2013, at 11:58 AM, Bob Albert wrote:
> Ah that time tick idea makes sense. Now I just have to figure out how to
> generate it from my time base. And of course, since I don't want to stay
> awake for several days, I a
u can improve your accuracy.
Bob
On Sep 26, 2013, at 9:24 PM, Bob Albert wrote:
> This is off topic but I'm unsure how to do it properly.
>
> I am trying to 'discipline' a couple of sources. I zero beat with 20 MHz WWV
> but can't tell the difference between fadin
u can improve your accuracy.
Bob
On Sep 26, 2013, at 9:24 PM, Bob Albert wrote:
> This is off topic but I'm unsure how to do it properly.
>
> I am trying to 'discipline' a couple of sources. I zero beat with 20 MHz WWV
> but can't tell the difference betw
on the radio. Compared over
a time span of days you can improve your accuracy.
Bob
On Sep 26, 2013, at 9:24 PM, Bob Albert wrote:
> This is off topic but I'm unsure how to do it properly.
>
> I am trying to 'discipline' a couple of sources. I zero beat with 20 MHz
This is off topic but I'm unsure how to do it properly.
I am trying to 'discipline' a couple of sources. I zero beat with 20 MHz WWV
but can't tell the difference between fading and the beat, so I am stuck in the
vicinity of 1 Hz possible error. That's 50 ppb I think.
What can I do to take th
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