Perhaps it is not a good analogy, but I think of
the cesium beam tube in the 5071A. The plans
alone are very non-trivial. Then there are
a bunch of proprietary machining details that
I can't disclose, that are way beyond the
merely having access to a CNC tool. The
systematic error due to the
On 4/13/2015 3:11 AM, John Miles wrote:
A comparator with less open-loop gain was what they needed. Somebody at HP
really liked ECL line receivers, though. Those were very noisy at HF, but this
had little or nothing to do with their bandwidth (see my other post.)
To square up a 10 MHz
On 4/13/2015 12:14 PM, Magnus Danielson wrote:
Oh yes. Some people say that you should not overcomplex things. My
experience is that oversimplifying them can cause a long stretch of
complex problems and complex workarounds making the total solution more
expensive in development, customer
On 4/12/2015 6:30 PM, Attila Kinali wrote:
It might be that I'm already too sleepy, but I don't see why
a faster comparator would add more jitter. Actually, my intuition
(which is clearly wrong) would say the contrary. So, which effect
does increase the jitter with comparator speed?
The
On 4/12/2015 2:22 PM, Magnus Danielson wrote:
Hi,
The buffer transistors has not AC-bypass of the emitter resistance, so
that the DC current becomes large and thus contributes flicker noise.
The comparator at the bottom isn't doing a beutifull work of squaring
things up without contributing
The 5071A doublers I designed use MCL ASK-1 mixers.
The LO and RF ports are connected in series. This
arrangement is self limiting. So you drive them
fairly hard and the output is level. The IF port needs
to see a DC short circuit of course. This was
essential in the 5071A since there were 5
On 4/12/2015 3:04 PM, Perry Sandeen via time-nuts wrote:
List,
For me it was simpler to buy asurplus HP 5087A for best offer which turned out
to be $300 delivered.
The 5087 series is ancient technology that has mediocre performance.
I remember looking at the circuit designs in the
On 4/12/2015 1:03 AM, Adrian Godwin wrote:
What caused that degradation ? I'm interested in dos/don'ts for best use of
a 10811.
I don't remember the details much after 25 years, but
basically they have a distribution amplifier that
allows for internal or external 10 MHz and what I
remember is
On 4/11/2015 5:01 AM, J. L. Trantham wrote:
Unless the design has been changed, the 10811 option
for the 53132 has poor short term stability and
degrades the performance of the 10811 by something
like an order of magnitude. I complained about
this when the counter first came out 25 years
ago but
Before the Keysight split, there was an Agilent
museum at HQ in Santa Clara. It was packed full
of interesting old HP stuff and even had a part
time archivist. I'm now retired and don't know
what became of this museum in the split.
I feel I got out while the getting was good.
Rick Karlquist
On 2/25/2015 4:32 AM, Attila Kinali wrote:
On Wed, 25 Feb 2015 10:16:58 +0100
Attila Kinali att...@kinali.ch wrote:
Actually, you should put the temp sensor close to the heater, not the crystal.
The delay between the actuator (heater) and the feedback (temperature sensor)
defines the dead
The other big difference is that the 10811 uses
an SC cut crystal instead of an AT cut crystal.
From a cold start, the SC achieves a given stability
much faster than an AT cut. If you are just going
to run the oven continuously (likely mode for time
nuts), this isn't any big deal to you.
The
PM, Richard (Rick) Karlquist wrote:
The other big difference is that the 10811 uses
an SC cut crystal instead of an AT cut crystal.
I stand corrected.
Rick
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On 1/29/2015 5:41 PM, Alexander Pummer wrote:
And the narrow notch for the harmonic is not required anyway, since the
fundamental is fare enough, therefore a high Q LC trap will work
better, also with the setting of the biasing af the active devices the
Alex KJ6UHN
When I designed the 5071A
First of all, the oven oscillator option of the 53230
is no where near as stable in ADEV as a 10811 for example.
The counter itself is 1 or 2 orders of magnitude better
than the built in timebase. So don't waste your money
on the OCXO option when you, as a time nut, undoubtably
already own
On 1/28/2015 11:28 AM, Charles Steinmetz wrote:
Gerhard wrote:
It is a different game when you want to notch away sub/harmonics.
One problem with using crystals as traps (notch filters) is that the
series resistance of a crystal is several orders of magnitude higher
than that of a good
We have DirecTV with some receivers standard
definition and others High Definition. The
delay is considerably greater on the HD version.
Even OTA HD is delayed considerably, as noted
if you try to listen to a football game on the
radio while watching. Sometimes you hear touchdown
before the
On 12/11/2014 4:20 PM, Bob Camp wrote:
Hi
Those OCXO’s were made to the spec’s of an OEM customer. The spec’s are owned
by that customer and can not be released without authorization from them.
Anybody who wants to stay in the business would be a bit crazy to release
somebody else’s
in is all
that really matters.
Bob
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Richard (Rick) Karlquist wrote:
On 12/8/2014 4:53 PM, Bert Kehren via time-nuts wrote:
We solved
/2012Issues.html
http://www.prc68.com/I/DietNutrition.html
Richard (Rick) Karlquist wrote:
On 12/8/2014 4:53 PM, Bert Kehren via time-nuts wrote:
We solved that problem by attaching the regulators to the FRK back plate
which is with fan control is kept within 0.01C. We did not do it for
that
purpose
On 12/9/2014 1:30 PM, ed breya wrote:
buried zener for lowest noise - this eliminates all the low voltage
references and three-terminal etc regulators that use band-gap
references. The down side is that the good kind of reference ICs will
need a higher (like 10V and up) operating voltage than
On 12/9/2014 3:02 PM, Bob Camp wrote:
Here's an overnight ADEV plot against the new Cs of where we are in
the project. Red is ADEV. Green is the TIC. Blue is the output of the
GPSDO to Channel A and the Cs to Channel B of my 5335A measuring TI,
using the 1PPS from my GPSDO to trigger the
Please Gerhard, more details on your choke
(medium size red Amidon core two 220 uH Siemens chokes).
Maybe I can use it for 160 meter antennas.
Your T1-1 measurements make sense according to
my experience with these things. The -6
series (T1-6, etc) has larger cores and should
withstand more
On 12/8/2014 4:53 PM, Bert Kehren via time-nuts wrote:
We solved that problem by attaching the regulators to the FRK back plate
which is with fan control is kept within 0.01C. We did not do it for that
purpose but found that we needed some more heat in order to keep the fan in an
optimum fan
On 11/30/2014 11:09 PM, Dr. David Kirkby (Kirkby Microwave Ltd) wrote:
I think I have a flaw in my understanding of this.
How can something like an SR620 measure the ADEV of an oscillator, if the
oscillator is of a similar or better than the reference fed into the SR620?
What HP did with
On 12/1/2014 4:08 PM, Bob Camp wrote:
Others did a similar thing by simply taking production OCXO’s to the limit of
their EFC range. That let you do a coarse sort to find some number of “likely”
units. Next step was to pop a few of them open and short this or that out to
get a reasonable
On 11/28/2014 10:08 AM, Dave M wrote:
Rick,
Thanks for the brief review of MiniCircuits stuff (I'm not connected
with them in any way except as a customer).
Since you've characterized some of their parts, perhaps you could help
answer a question that someone else posted, and one that I would
On 11/28/2014 1:04 PM, Bob Camp wrote:
If you do need to run substantial current through a choke core, the larger
binocular cores with a half turn through them are a better choice.
Still useless for 20A (or even 2A) though …
Bob
The binocular cores come in several hole sizes.
All other
On 11/27/2014 7:07 AM, Tim Shoppa wrote:
For a hobbyist doing things a few at a time, what advantage is there to
buying RF transformers made by Mini-circuits etc., vs winding them using
commonly available ferrite cores/binocular cores?
If I needed to do a production run of 1000+ boards with
On 11/27/2014 9:09 AM, Tim Shoppa wrote:
On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp kb...@n1k.org wrote:
The main complaint is the difficulty of getting the correct cores. I seem
to have a few dozen bags of cores.
The mainline distributors (Allied, Newark, Mouser, etc.) have excellent
On 11/27/2014 11:03 AM, Didier Juges wrote:
Another reason is reproducibility. If you or someone else wants
to reproduce your design, using a well defined and available
commercial part makes it much easier to achieve the same
performance, particularly for RF components.
Didier KO4BB
I did some checking around for low noise buffer amps earlier
this year. They needed to have 200 MHz bandwidth, so this
isn't directly applicable to 10 MHz. I also needed isolation.
About the only information in print is from the usual suspects
at NIST. They wrote a series of papers taking a
See:
http://newsoffice.mit.edu/2014/portable-atomic-clocks-1112
Any comments?
Rick Karlquist N6RK
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On 11/17/2014 5:54 PM, Bert Kehren via time-nuts wrote:
I ground one side of the tuning diode and use the 2 to 12 V as the external
OCXO for my FRK's along with increasing the time constant. I have not
verified it but I think removing the zener Voltage should also improve ADEV.
Bert Kehren
temperature ranges.
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Richard (Rick) Karlquist wrote:
On 11/17/2014 5:54 PM, Bert Kehren via time-nuts wrote:
I ground one side of the tuning diode
Hi, I was the designer of the board, but I don't remember the
part number of the reference. I will try to consult my paper
schematic when I get a chance, if no one else can help you.
I do remember that I originally used some convenient reference
which seemed OK from the data sheet, but turned
This dispute reminds me of another one.
A long long time ago, .gif was the internet
standard for encoding photographs. Far and
away the favorite. Then the owner (was it
AOL?) decided to enforce their patent by
getting snotty with end users. Almost overnight,
.gif virtually disappeared off the
On 10/7/2014 10:02 AM, Jim Lux wrote:
At work, I'm putting together a multichannel stepped frequency CW radar
breadboard, and I'm looking for something to serve as a source that I
can step quickly.
Possibly overkill, but Agilent has a very state of the art
arbitrary waveform generator that
- Original Message -
From: Richard (Rick) Karlquist rich...@karlquist.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Cc: hmur...@megapathdsl.net
Sent: Wednesday, October 01, 2014 9:03 PM
Subject: Re: [time-nuts] How long do ovens take to cool to ambient after power
On 10/1/2014 1:04 PM, Hal Murray wrote:
drkir...@kirkbymicrowave.co.uk said:
Anyway, later today (tomorrow ??) I will post a plot of frequency vs time.
The question is though, how long is thing thing likely to take too cool?
I'd expect an exponential decay so you need to specify how close to
I am just speculating that this oscillator was used
instead of the 10811 because the 10811 would not fit.
Therefore, it would NOT be used in other equipment.
I would guess the specs would be similar to the 10811.
The 70,000 series had some general purpose power bus
that the McCoy would have to
On 8/17/2014 12:30 PM, paul swed wrote:
OK
That said I shared the tracor d-msk-r circuit with the group that removes
the msk. How does it pull that trick off? I do not get how it gets rid of
the msk and leaves the carrier.
A common way to remove BPSK is to simply run the signal
through a
Without having seen the specific patent, what
worries me is that there is a trend these days
to write blanket patents that say you can't
build any black box that, for example, receives
this format, no matter how it works.
They don't have to prove what is
in your FPGA code. They then can shut
On 7/28/2014 1:12 AM, David C. Partridge wrote:
Back to time related discussions please.
Thanks
Dave
I worked on cesium standards (5071A)
at HP/Agilent with Len Cutler of flying clock
fame. You better believe that batteries are
time related. We jumped through all sorts of
hoops to get the
On 7/24/2014 9:37 AM, Tim Shoppa wrote:
The data and tests presented in this source:
http://www.cliftonlaboratories.com/imd_in_broadband_transformers.htm
is a great resource on measured large-signal performance of
binocular/toroidal transformers. One factor found that can really degrade
IMD
I did some tests of residual phase noise using an
Agilent E5505A and found that air coil inductors
did not add noise (at least down to my noise threshold)
but that ferrite core inductors had easily seen noise.
It was on the order of ADEV = 1E-10 close to the
carrier. I would describe this as
On 6/2/2014 7:43 AM, Attila Kinali wrote:
Also, any good resource on how to build a directional coupler that
does 10-3000MHz without going to exotic materials would be much
I once had the opportunity to discuss directional couplers with
Julius Botka, then with HP/Agilent. Specifically, a
On 6/2/2014 12:41 PM, Brooke Clarke wrote:
Hi:
I started with the HP 8410 and added an external computer.
Since it can be used manually I think it's an excellent way to learn
about VNAs.
http://www.prc68.com/I/MWTE.shtml#NA
For my last 8 years at Agilent before retiring in March, I
was doing
will also look better than it really is, and for the same reasons. (Some
people have even reported similar behavior with cesium standards,
although I
don't see how that could happen. There aren't supposed to be any
first-order temperature effects in a CBT, and I'd think that any
lower-order
On 5/29/2014 9:15 AM, cdel...@juno.com wrote:
On these latest oscillators at the longer Tau (100sec.)
the Quartz versus Quartz data shows much better performance
than the Quartz versus Maser!
What is happening (I think) in this case is that both Quartz units
have exceptionally low and similar
I was the Project Manager for the 5334B.
The A version (unlike the B version) has
a very weak power supply due to insufficient
capacitors and/or transformer. I can't
remember now after 25 years. When you
power it up with a cold 10544 or 10811, the
oven circuit looks like a 47 ohm resistor.
The
I will be at Dayton this year.
I'll see if I can rattle the cage.
Rick N6RK
On 5/12/2014 6:32 PM, Robert LaJeunesse wrote:
Just a note that there will be some Time Nuts at the Dayton Hamvention this
weekend. Don't be surprised to run into one or more at Flea Market spaces FW
1902/3/4/5.
My understanding is that a really good Rb standard
use a fairly wide bandwidth loop to control its own
internal XO, and therefore improve its close in phase
noise to be better than you can get with quartz alone.
The Rb standard is able to do this because the S/N
ratio of its rubidium vapor
It is very easy to make an impedance phase detector by
inserting a toroidal current transformer in series with
the load under test. The center of the secondary is
connected to the load through a capacitor. Each end of
the secondary goes to a diode detector. When the
load is resistive, the DC
I worked for the HP Santa Clara Division during
the Smart Clock days and knew all the players.
In terms of holdover, the report cited mentions
temperature compensation and learning aging.
The temperature compensation was simply a crutch
for the 10811 to fix its tempco problems. The
E1938A had
On 4/11/2014 11:04 AM, Hal Murray wrote:
How many would you need? Is 3 enough?
How well could you do with several low(er) cost oscillators relative to one
good but expensive one? It might be an interesting experiment in a nutty
sort of way.
My guess would be 3 would be a minimum, so you
The trouble with ADEV is that if you average
a long time it papers over anomalous events
like crystal jumps. An alternative measure
might be to, instead of averaging, simply
keep track of the worse case change in frequency
during 1 sample period. Sort of like peak jitter
versus rms jitter.
Solid dielectric cable and connectors of 3.5 mm size
are mode limited to 18 GHz. That is why there is
so much stuff rated at 18 GHz as opposed to 16 or
20 GHz. The next jump up is 26.5 GHz where 3.5
mm size works in air dielectric. It costs more
to make these components and the volume is
I couldn't get the link to work (it just hangs).
However, I vaguely remember when we were starting
work on the 5071A that the reason why we used
the model number 5071A instead of 5070A was that
the latter number had been reserved for a hydrogen
maser that was never sold. The person in charge
of
On 2/24/2014 8:54 AM, Pete Lancashire wrote:
Does this hang ?
http://www.hp.com/hpinfo/abouthp/histnfacts/publications/measure/
That works, but when i click on the actual link to the
actual, my browser still hangs.
Rick
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Still doesn't work for me.
On 2/24/2014 8:57 AM, Had wrote:
http://www.hp.com/hpinfo/abouthp/histnfacts/publications/measure/pdf/1968_09
.pdf
Rick, I got the above to work with no problem. The original link was busted.
Had
K7MLR
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On 2/24/2014 1:59 PM, dlewis wrote:
The.pdf got caught up in a linefeed/carriagereturn
Wouldn't that problem result in a file not found error
rather than just hanging?
I eventually got the link to work from Internet Explorer,
which took 5 minutes to download it. It never worked
It may be true that WWVB is sending out a new
format, but the receivers for it don't seem to
exist. The exclusive rights are held by this
company, which is clearly on hold while it
tries to find a customer who will pay for a
wafer run:
http://eversetclocks.com/
I've seen this sort of thing
Can anyone recommend a atomic wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
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Thanks for the suggestions, but the MFJ121 does not
display the date and the Lacrosse 8055 and 8016
do not display seconds. I need hour minutes seconds
day and date. You wouldn't think that would be
so hard. It looks like my only choice is this
smallish wall clock (more like a desk clock):
On 2/19/2014 6:35 PM, Chris Albertson wrote:
On Wed, Feb 19, 2014 at 3:52 PM, Richard (Rick) Karlquist
rich...@karlquist.com wrote:
Can anyone recommend a atomic wall clock
that displays in digital 24 hour UTC?
Any reason why it was to by WWVB? What if it used some other means of
saying
CORRECTION:
The 8005 series (with indoor temperature) does not support GMT
Only the 8115 and 8119 series (with indoor and outdoor
temperature) support GMT.
On 2/19/2014 5:47 PM, Richard (Rick) Karlquist wrote:
so hard. It looks like my only choice is this
smallish wall clock (more like
On 2/19/2014 9:10 PM, John Marvin wrote:
I guess my question is who has the right to grant exclusive rights for
the ability to decode a very simple protocol? Was a patent actually
granted for this?
John
They have exclusive rights to the IP core for their IC.
I guess someone else could
On 2/5/2014 9:37 AM, Bill Hawkins wrote:
Then there is the load side, with who knows what equipment making large
swings.
This reminds me of the time I visited the John Deere
foundry in Waterloo, IA. They had an arc furnace with
graphite rods the size of small utility poles. I
remember
On 1/30/2014 7:50 PM, John Miles wrote:
Exactly, for unity gain you'd design for +6 dB and series-terminate the
output with 50R. Good for capacitive loads as well as isolation.
Do you run it in inverting or non-inverting configuration?
I've only used the non-inverting configuration
On 1/30/2014 12:30 AM, John Miles wrote:
Depending on how much forward gain you're after, I'd suggest looking at the
LMH6702 current feedback opamp. I keep a few of them around in Hammond
boxes, powered by NiMH rechargeables. Measured S12 is about 70 dB at 100
MHz, and I'm sure it could do
Can anyone direct me to an amplifier with:
1. High reverse isolation
(over 40 dB). Note: the spec of interest
is *reverse* isolation, not port to port
isolation in a distribution amplifier.
2. Low phase noise
(less than -100 dBc/Hz at 1 Hz offset)
3. Works at 200 MHz
The Q-Bit QBH-1401PM
On 1/28/2014 10:26 AM, cdel...@juno.com wrote:
Hi,
Does anyone know where to find the primary inductance value for Mini
Circuits RF Transformers?
I need to know so I can pick one to resonate with a particular capacitor
at 5Mhz.
At 5 MHz, the core is probably more resistive than inductive
On 1/13/2014 7:36 PM, Rex wrote:
This document lists that part number...
http://www.leapsecond.com/museum/10811a/90027-1.pdf
It says (I think -- in a quick scan) that it is mostly the same specs as
a 10811 D/E except a narrower EFC tuning range.
When HP was doing the smart clocks circa 1997,
FYI:
http://www.hp4815a.com/
This guy did great work for me
in 1995. Seems to know everything
about this instrument. Had no idea
he was still in business.
Rick Karlquist N6RK
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On 12/30/2013 9:37 AM, Gerhard Hoffmann wrote:
Driving the DDS system clock from an expensive RF generator (e.g. HP
8648A)
would be possible but I'd prefer a PLL from 10MHz if it's doable
simply/cheaply.
Although expensive from a hobbyist viewpoint, the HP8648A is
far from HP/Agilent's best,
On 11/1/2013 7:12 PM, Tom Knox wrote:
A while ago I mentioned 5MHz oscillators were used in most metrology
applications compared to the more commonly available 10MHz because 5MHz was a
sweet spot for quartz. At the time I didn't know why. I finally had a chance to
ask the person I learned
On 11/1/2013 8:28 PM, Bob Camp wrote:
HI
If you doubled the diameter of the blank each time you cut the frequency in
half, all sorts of nice things might happen. If you start with a 1/2” blank in
at 10 MHz that goes to 1” at 5 MHz and 2” at 2.5 MHz. Around 1 MHz you would
get to a 5”
In a free running (non crystal controlled) oscillator,
the oscillator with the highest Q (regardless of frequency)
will have the best phase noise, if all oscillators are
normallized to the same frequency by ideal multiplication.
So the Q gain doesn't go away in that sense.
Having said that, in
We have two sources and we want to be able to measure their
frequencies at the same time. We want to get a time record
of frequency each second. Apparently, what is meant
by a two channel frequency counter is that you get the
frequency of either channel A or channel B but not both
at once.
Thanks for the info. I wouldn't have suspected those
little gain blocks were so good, and the voltage
bias problem makes sense.
Rick
On 9/30/2013 5:53 AM, Garry Thorp wrote:
Mini-Circuits' GALI- series of InGaP MMICs work pretty well. They typically
have ~4dB NF, and the noise performance
I have an 18 GHz HP 5342A frequency counter, which I don't seem to see
a lot, as members of my radio club borrow it. But it has no oven.
There is an option for an oven, but my model does not have the
optional oven fitted. I don't know if it would take a 10811A - if so I
might fit one, since I
I'm looking for information about mounting (packaging) quartz
crystals with conductive epoxy such as:
1. Recommended type of epoxy.
2. Curing time and temperature.
3. Surface preparation of the gold.
4. Experts/consultants in this area you could recommend.
(Note: this refers to mounting
On 6/30/2013 8:47 AM, Attila Kinali wrote:
Most of the oscillator circuits out there place a small, but constant
DC voltage on the crystal, which has the same effect on the ions as
FWIW, the HP 10811 definitely does not do this (according to its
designers) since the crystal is capacitively
An interesting technique used many places including HP is to have
a radio receiver connected to a pickup coil in the vicinity of
the grinding machine. The vibrations of the abrasive wheel
cause pings in the receiver at the resonant frequency. It
doesn't seem like this would work, but it
1. Is the 200 Hz drift measured at 660 kHz or at the final frequency,
perhaps 1.8 MHz? Even in the latter case, we are talking about 100 ppm.
2. Was the rig stable before and something changed? You didn't say.
3. Have you verified that the drift is not simply due to the crystal
itself? A
At HP in the 1990's, Len Cutler's group built some experimental
mercury ion standards for USNO (IIRC). They were of the
trapped ion type. BTW, it is important to understand that
the architecture is the key factor, not the flavor of atom.
When people say rubidium is inferior to cesium, they
On 4/14/2013 7:48 AM, Brian Davis wrote:
Not sure if it's already been mentioned, but Linear has introduced a new
part that looks interesting :
LTC6957 Low Phase Noise Buffer/Driver
http://www.linear.com/product/LTC6957-1
This is VERY interesting, especially the low noise PECL output. I have
OK, so we seem to have:
1) Scotch 130 rubber tape
2) Scotch 33 electrical tape
3) Scotchkote
in that order.
So the rubber tape waterproofs
the connection and the scotch kote
protects it from UV, so what does
the electrical tape do?
Or maybe, the electrical tape does
the waterproofing and
Richard (Rick) Karlquist:
Actually, the opposite is true. Notches have the least phase
shift at the frequency being passed, which is what matters.
It is true that the phase shift at the notch frequency is
uncontrolled, but that is not important. The HP8662A
had an interesting PLL synthesizer where
Actually, the opposite is true. Notches have the least phase
shift at the frequency being passed, which is what matters.
It is true that the phase shift at the notch frequency is
uncontrolled, but that is not important. The HP8662A
had an interesting PLL synthesizer where they had 10 notch
On 3/17/2013 4:54 PM, Volker Esper wrote:
The HP seems to be the more modern design. As I guess, the analog
circuits are to blame, maybe HP was able to make use of newer technologies.
FWIW, the 53132A design goes back 20 years
Rick
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One more thought: Many oscillators have internal regulators that are not
nearly as good as what you can build. No sense using an external supply
with 5 nV per root Hz noise density if it will be re-regulated inside
the oscillator by a circuit that has a noise density of 250 nV per root Hz.
I know this topic has been discussed in the past on the list, but
a colleague is asking if there are any off the shelf low
noise power supplies for testing oscillators. Something
a cut above an HP brick lab power supply etc. They are hoping
to avoid having to homebrew a power conditioning
The old Watkins Johnson M9 series was the state of the art for
stacked diode mixers. You can still get the M9E and M9H from
MaCom Technology Solutions. The M9E is better, but only if you
have the 1/2 watt! of LO drive needed. As you have done already,
it is probably possible to homebrew
On 11/23/2012 9:38 AM, Bruce Griffiths wrote:
NIST have shown (at least at 10MHz) that the high level mixers they
tested are noisier than the ZRPD1.
Bruce
Do you have a citation to where they said that?
What you quoted doesn't make sense, at least, out of context.
We need to clarify phase
On 10/13/2012 8:30 AM, Adrian wrote:
12V for the oven because inside the outer oven lives a 10811-60158 ( see
http://www.realhamradio.com/GPS-oven-journey.htm ) that, as by the specs
sheet, is specified 12 to 30 V DC, 11 W max. at turn on (mine draws some
9 W), and Steady state power drops to
On 10/4/2012 9:45 AM, Tom Van Baak wrote:
Bob,
Right, not good. There should be a fault message associated with it. Check the
internal log.
OTOH, to conserve cesium, I've heard that some people run 5071A in standby mode
most of the time and only turn on the cesium for a fraction of an hour
These ideas are interesting. AFAIK, there is very little
chance of running out of Cs in many years, long past the
time when something else in the tube will have reached its
end of life. Where did this idea come from? Certainly, not
anyone working at HP, Agilent or Symmetricom. A LONG time
and the loading of the
bridge oscillator.
Bob
On Sep 29, 2012, at 11:46 PM, Richard (Rick) Karlquist rich...@karlquist.com
wrote:
The E1938A uses a crystal that is basically the same as
the 10811 crystal except that it is in a reduced height
package. However the phase noise is not as good as a
10811 due
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