I was wondering if there is any interest for a single oven HP 10811
improvement design kit of some sort?
Background:
I am now using a double oven 10811 as the Freq reference for my own
projects.
Some recent off line conversations made me realize that there are many
advantages to using a
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Dave wrote:
I feel that a simple Bang Bang (?) controller is not going to give you what
you seek.
To get truly accurate and stable temperature control, you will almost
certainly need a full PID controller, with some sort of variable
control of the heating element.
Not a bad idea, AND
That may not work either,
Go with the 100KHz stop
Also needs to pick the right edge of the High freq stop signal.
If the edge that is picked is bouncing back and forth around the start pulse
It don't work so good.
ws
*
Bruce wrote:
That won't work as one of the sources is the
Something that I often find unasked is
a) How much difference does it make?
b) Are there simpler ways to get the same or better results.
Concerning the home made Choke ring antenna, Nice job for a survey nut
BUT for freq nuts
I'm wondering if placing an 8 inch PiePan with its lip up between the
Next on my list of things to try is a smaller open taco maker deep dish
metal pan.
Preliminary results for the Taco Dish GPS antenna as an indoor antenna are
looking good.
Certainly worth considering if your GPS antenna is stuck indoors, 'Out of
the rain in the living room'.
I find it best to
use a solution derived from the
processing of the coarse acquisition code, in were the receiver is in a
fixed over-determined position . Some timing labs are using carrier phase
method, when they need more resolution.
Brian - KD4FM
warrens wrote:
...
Preliminary results
measurements with geodetic antennae:
http://www.fig.net/pub/fig2008/papers/ts05g/ts05g_03_eventzur_shaked_2816.pdf
Comparison of code phase and carrier phase time transfer:
http://tycho.usno.navy.mil/ptti/ptti2004/paper41.pdf
Bruce
**
WarrenS wrote:
Brian wrote:
There were also
**
WarrenS wrote:
Bruce wrote:
Which antenna performance metric do you have in mind?
Could do GPSDO hold over performance, but that would not be much of a
test of the antenna.
How about the antenna's effect on the ADEV Osc noise and Phase noise.
What else does the Time Nut care
yeah,
So many variables, ALL the more reasion to just see what the overall effect
is on the more common type of GPSDO receviers at a few sites.
So did you have a better plan?
ws
Bruce Griffiths Added:
WarrenS wrote:
Bruce wrote:
Which antenna performance metric do you
characteristics
of the OCXO being used.
Bruce
WarrenS wrote:
yeah,
So many variables, ALL the more reasion to just see what the overall
effect is on the more common type of GPSDO receviers at a few sites.
So did you have a better plan?
ws
Bruce Griffiths
As is often the case, this discussion has spun off into several different
directions.
I'm not trying to make a choke ring antenna, because I do not think it is
necessary for a Tbolt.
I'm just suggesting a way to get better performance from a Tbolt GPSDO if on
a limited budget, using things
What I have found is if you have a decent view of the sky or even when
indoors on an upper shelf,
by turning the pie pan lip up, it helps the antenna location placement
sensitivity issue.
I'll leave it to the antenna Experts speculate on why that is.
ws
***
Hi
That's one of the
antenna
This is attached to a PBC pipe raised just above my roof line
ws
Warren,
I'm not trying to be a wise guy, but what direction is right other than
up?
Steve
At 08:46 PM 3/13/2010, WarrenS wrote:
**
All true,
BUT...
Just put an 8 inch pie pan
Good information to know, if one is doing survey work.
But some NON-Nut needs to ask, SO WHAT?
A 3 foot error may cause + - 3ns of additional phase time error, which is
well below the short term GPS noise level.
If that is averaged over the 500 or so second TC loop or the 48 hrs supper
survey
Is there a design for a choke ring to add to my existing L1 GPS antenna ?
Yeah
If you are using it for GPSDO work where a ns is good enough and you don't need
cm accuracy,
It is called a pie pan with its Lip turned up.
A choke rings blocks reflected signals from below the antenna from
Any one of the counters listed above can do this measurement,
A decent time nut Allan Deviation needs to have noise floor of below 1e-12.
To do this for a 1sec ADEV, it needs a resolution of under 1ps, so NO not all
the counters can do that.
ws
On Mar 13, 2010, at 10:23
All true,
BUT
Just to keep from being mislead,
I said what a choke ring antenna does,
You have described how it is so good at its job.
The Main purpose of the choke ring's, hi impedance, 1/4 wave, tuned
thingies, around the antenna is to keep reflected Signals from BELOW the
antenna from
***
WarrenS wrote:
All true,
BUT
Just to keep from being mislead,
I said what a choke ring antenna does,
You have described how it is so good at its job.
The Main purpose of the choke ring's, hi impedance, 1/4 wave, tuned
thingies, around the antenna is to keep reflected Signals from
.
ws
* WarrenS wrote:
Bruce wrote:
ws response
Only for your particular location and antenna.
True, My location is under the sky indoors or outdoors, and I used
several cheap car type antennas and a pole mounted timing antenna.
May not work as well in other locations
, Most any general purpose
Regulated supply will work fine.
To help explain in more detail,
Bob added:
A common mode choke might also be a good idea,
[to use in several places, to clean up and remove high freq and audio noise
caused by switcher etc.]
WarrenS added:
TRUE, BUT A Common mode choke
Yes, I Did that, The +5 and -12 has NO effect on freq or operation of the
unit except for really far out voltages.
I tested mine with the -12 from -2 to -15 and could see no effect in the
e-11 range.
The -12 is used for the RS232 and the -Dac out so If you don't need the neg
Dac out
? Is it
running the maser reference for the DAC or does that come off the +12? Is +5
just a digital supply?
Lots of questions
Bob
On Feb 26, 2010, at 6:59 PM, WarrenS wrote:
Yes, I Did that, The +5 and -12 has NO effect on freq or operation of
the unit except for really far out voltages
*
Hi
Please explain how a common mode choke on the +12 and ground does nothing to
help keep the supply clean.
Bob
*
On Feb 26, 2010, at 9:57 PM, WarrenS wrote:
Lots of questions
Same Simple answer.
Make the +12 volts is as good as you can get it, For the rest any
supplies the
rectified line is what's coming through.
Bob
**
On Feb 26, 2010, at 10:10 PM, WarrenS wrote:
Common mode choke filter does not get ride of LINE NOISE on the +12 V or
LINE VOLTAGE sensitivities...,
Please explain how a common mode choke on the +12 and ground does
All very informative and useful information for sure and good to know,
But I'm thinking the real difference between a primary and secondary
standard,
Has More to do with if there is anything else more accurate and repeatable
available.
I'd guess a Rb would of made a great cave man Primary
being
calibrated against a better clock. Secondary means that
calibration against a primary standard is necessary.
Rick Karlquist N6RK
**
WarrenS wrote:
All very informative and useful information for sure and good to know,
But I'm thinking the real difference between a primary
of that
or any other accomplishment.
Primary means that the clock will meet its spec without being
calibrated against a better clock. Secondary means that
calibration against a primary standard is necessary.
Rick Karlquist N6RK
**
WarrenS wrote:
All very informative and useful
**
**
WarrenS wrote:
All very informative and useful information for sure and good to know,
But I'm thinking the real difference between a primary and secondary
standard,
Has More to do with if there is anything else more accurate and repeatable
available.
I'd guess a Rb would of made
**
From: WarrenS
It is said a picture is worth a thousand words, A good graph even more.
Attached is a Lady Heather, 2 day long plot showing the difference in
performance
of a TBolt GPSDO disciplining a Double Oven and a Single oven HP10811 Osc.
The Single oven Osc is the same exact
another way, if you want under 1ps ADEV nose,
Need to keep the Buffer's wide bandwidth phase noise down around 1 ns or 1%.
**
From: WarrenS
Magnus said
White noise goes down into the lower range and do contribute to the
ADEV
Can you put some numbers to it to show how much effect
In the ever ending battle to improve my TBolt's performance, I am in the
process of upgrading a OCXO replacement I did to it a while back.
It would be Interesting to hear suggestions from others that have done similar
sort of things and the results they have achieved.
ws
Looks like 40kW
What's that mean,
For those of us not familiar with those units, can you give that in the new
standardized USA government units of, CARS OFF THE ROAD. :-)
**
Hi
I wonder what just the electric bill is to keep a single chain (4
transmitters) up and running?
will not
be ADEV, MDEV etc.
Bruce
WarrenS wrote:
Thanks to the persistence and comments of others,
I have marked up an old NBS diagram to show, anyone that wants to learn,
how the Tight Phase lock method works to do its 'Magic'.
Although it can be very simple and cheap to build, It does take
If there are any Nuts out there interested in helping to make available to
other Freq-Nuts a SIMPLE tester that I have found to be a VERY useful low
cost tool, contact me off line.
warrensjmail-...@yahoo.com
The tool is based on an OLD but seldom used method called the Tight
Phase-Lock
John Green said:
The thing that surprised me was how much a TBOLT's [phase] moved around
compared to my Z3801.
That will be the case if you are using the Tbolt's default tuning
values.
ws
*
[time-nuts] Measuring frequency difference
John Green wpxs472 at gmail.com
Peat said:
I would appreciate any comments or observations on the topic of apparatus with
demonstrated stability measurements.
My motivation is to discover the SIMPLEST scheme for making stability
measurements at the 1E-13 in 1s performance level.
If you accept that the measurement is going
for Tau more than a few times the inverse PLL
bandwidth.
Thus NIST and others quietly dropped this method several decades ago.
This is alluded to in Steins recent paper availble on the Symmetricom
website:
*The Allan Variance – Challenges and Opportunities*
Bruce
WarrenS wrote:
Peat said:
I
coefficients along with thermocouple effects could make things exciting.
There is no perfect way to do any of this, only a lot of compromises here
or there. Each approach has stuff you need to watch out for.
Bob
--
From: WarrenS warrensjmail
aliasing and
average (ie integrate) the individual EFC samples.
If one uses phase measures then the fluctuations in the frequency
averages can easily and directly calculated from the difference between
the phase measured at time intervals separated by Tau.
Bruce
WarrenS wrote:
Bruce said:
Thus
simple (2 stage) limiter.
As with the DMTD, the counter requirements aren't really all that severe.
Bob
*
On Feb 6, 2010, at 4:24 PM, WarrenS wrote:
It's possible / likely for injection lock ... to be a problem ...
Something I certainly worried about and tested for.
What
in the frequency
averages can easily and directly calculated from the difference between
the phase measured at time intervals separated by Tau.
Bruce
WarrenS wrote:
Bruce said:
Thus NIST and others quietly dropped this method several decades ago.
Could it be another reason?
I'll bet
An ADEV noise floor of 1E-13 isn't likely when using an HP10811A as the
VCXO for example.
How quickly one forgets and gets lost on these long topics.
If you accept that the measurement is going to limited by the Reference
Osc,
for Low COST and SIMPLE, Can't beat a simple analog version of
of the range of validity of the technique.
Bruce
WarrenS wrote:
An ADEV noise floor of 1E-13 isn't likely when using an HP10811A as the
VCXO for example.
How quickly one forgets and gets lost on these long topics.
If you accept that the measurement is going to limited by the
Reference Osc
need to get luck with your
frequencies if the heterodyne reference is not tunable. Something like a
10811 is indeed needed in a tight lock system.
Bob
On Feb 6, 2010, at 6:55 PM, WarrenS wrote:
An ADEV noise floor of 1E-13 isn't likely when using an HP10811A as the
VCXO for example
Another really Off topic subject, for the serious thinkers in this group.
Evolution Over TIME
Easy enough for one to imagine how evolution, using DNA mistakes etc. and
given enough time and random luck,
could change pond scum, a little at a time, into higher life forms with
their complex
then a 10811A with an aging rate of 5E-10/day
will require manual retuning every few hours.
Typical aging may be better than this but this would still require manual
tuning every few days.
Bruce
**
WarrenS wrote:
John ask
Translating nV/sqrt(Hz) to something
practical
Lots of fun little details to worry about managing
ws) TOO True.
A temporary attenuator bypass switch or syncing at a higher freq are two of
many ways to help the initial lock up delay caused
when a high value Dac attenuator is used to lower the effect of EFC noise
and / or to
John ask
Translating nV/sqrt(Hz) to something
practical is basically the assistance I'm looking for here.
I would appreciate anyone being able to teach me a bit more about this.
If that is ALL you want to know, That's easy and quick.
For this application sounds like you already know ALL you
together with
the OCXO noise and drift will dominate.
Unless you make an extremely poor choice of opamp the 4046 phase
detector noise and drift will be much larger than that of the opamp.
Bruce
WarrenS wrote:
John ask
Translating nV/sqrt(Hz) to something
practical
Filip
I do not understand why filtering is not use more to see what is going on.
At the VERY least should display the moving averages for freq.
As I hope you can see on the XL plot attached, as compared to the other
plots previously shown,
a good filtered signal shows more than JUST a little
Interesting
So a 100% error (1e2) would then be 40.4GHz and not 80GHz
Sounds like some new math the cost of living department came up with.
ws
**
Bruce Griffiths bruce.griffiths at xtra.co.nz
Tue Jan 5 20:25:05 UTC 2010
One should of course be aware that the number notation used is
Mike
Assuming you have learned to tame some of LH behavior issues, and that is
not what is causing the problems then:
MB) the temperature graph exhibits a sharp, which recovers over a period
of a few minutes.
ws)Likley a basic 'bug' in the LH Hardware. Best to ignore it.
MB) blue PPS
Mark
In part it depends on your TC and Damping settings as well as how sensitive
your Osc is to temperature.
And just as important is how well your temperature controller is really
doing at holding the OXCO's temperature.
From what I've seen, It is just as likely the Fourier spike AND the Temp
The problem with cooler chips is ...
The Real Problem seems to be some don't have much practical sense.
A peltier would work GREAT, (along with many other simple active ways).
You don't need to make a refrigerator with it.
You just need to just keep the temperature of what it is attached
Hey they cool EVEN better if you keep the hot side cold so there is a negative
delta-T.
On Dec 24, 2009, at 11:54 AM, J. Forster wrote:
The trick is you use the TE devices at near zero delta-T. They will pump
much more heat and dissipate little power.
-John
===
I Must not get it, Or I'm missing something.
Some seem to be going on and on about a little added DC heater current that can
be held to about 10% of what the unit draws
Why does a little added DC heater current any more of a problem that what you
do with the leads etc of the main power?
(And
OR you could use a small PC type IC cooler fan blowing at the heat sink from a
short distance away, driven from a Lady Heater type variable speed fan active
PID Temp controller.
That has NO trouble holding 0.01 Deg C at where ever you place the Temp sensor,
over normal day / night room
, but in this case you want to control the entire
device. Gradients and the change in gradients matters quite a bit.
Bob
-Original Message-
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of WarrenS
Sent: Wednesday, December 23, 2009 9:39 AM
To: Discussion
Sounds like a Volt nut question
Many ways to do it, some real simple, depends on
How far and how good it has to float and how stable/accurate it has to be.
ws
*
Richard W. Solomon wrote:
I am looking for a Voltage Reference chip that will take
a 12 volt source and give me
Some ways can be real simple.
FOR the simplest and BEST isolation use,
a 9 volt battery to power a low current 1 to 5 volt Ref + amp if need be.
You are not going to float very far with a 12 volt PS and 10 volt reference
without some extra stuff.
Sounds like a Volt nut question
Many ways to do
...@theiet.org
To: WarrenS warrensjmail-...@yahoo.com; Discussion of precise time and
frequency measurement time-nuts@febo.com
Sent: Wednesday, December 16, 2009 4:54 AM
Subject: Re: [time-nuts] Tbolt Damping setting
Good points, and You got 4 1/2 out of five correct, Not bad at all.
Ha ha
Peter
and all,
Good points, and You got 4 1/2 out of five correct, Not bad at all.
#1) YES, The easy way I used to make the controlled phase error steps was by
entering a new number into the cable delay, which is limited to under 50ns
change.
#2) Yes, this is the self reported Tbolt data
John
Thanks, that puts things a bit more in perspective.
Sometimes One persons 'A lot' is another persons 'almost Great'.
5 min = 300 sec
As much as 30 ns / 300 sec = 0.1ns /sec = less than 1e-10 freq shift
A lot of NON broken things can cause that kind of small drift.
With under 1e-10
John
Comparing Z3801 and Tbolts, although they do the same thing, Is hard, like
apples and oranges.
Depending on what performance one is after, they both have strength and
weaknesses.
One of the Z3801 biggest advantages is it Double Osc. The size and original
cost of that one item is likely
Rich
You don't need a double oven with the E1938A
Maybe the E1938A does not need it,
BUT it SURE does helps the average OXCO to keep it at a VERY constant temp when
looking at parts in e-12 freq changes.
How about the 10811-60158?
I think? that (or some version of it) is what is used in the
John Green said:
mine got a lot worse with TC set to 500 sec.
Depends if that was Short term Osc Freq noise or long term Phase drift?
Short answer:
A TC of 500 can causes a LOT more (x10 +) long term Phase shift error if the
temp is changing,
especially when the Dac_Gain and Damping are
Said
Double OCXO's rule!
Agree,
Should have a talk with Mark Sims, He has a neat, simple, No cost, double
oven solution for the Tbolt using Software...
There goes your plug and play, Can't have everything (Yet)
ws
**
- Original Message -
From: saidj...@aol.com
Said
I know this is not something that you really want to have to fiddle with,
but you may find some of it useful information.
More Default changes you may want to consider are:
With the default Dac Voltage setting of 0 and
the Default Survey setting of DO NOT save position
If the power fails,
Mark
Great info
Can you also see what 0.0, 0.5, 1.0, 1.5, 2.5, 3.0 are equal to.
Those are the important ones when setting the AMU lower.
AND better estimate what the hysteresis is at each setting,
It is about two or three dBc units
ws
***
- Original Message -
From:
Said
Not bad at around + - 15 ns Peak over a day,
IF I got the scaling right it is about 2 hrs division
AND there are around 3 hr cycles (10k sec) in the phase (along with lots of
other stuff)
If it is the Tbolt which is likely, then it is due to some of the other things
I warned about
/tvb
- over approx what time frame was that RMS average taken?
a day or so, or forever? if nothing disturbs anything.
- what frequency reference did you compare against?
GPS, For the most part Using Lady heather plots.
Which is Just comparing it to the filtered GPS, and does not take into
Said
I'd sure guess a good disciplined rubidium should win over the Tbolt.
But if the Tbolt does not come in a close second,
Give me another chance to change some of your other default setting.
It would be interesting to see what the ADEV plot looks like using Ulrich's
plotter program. .
OR
Tom said
I'd worry some about a TC that's too long. There's also the issue
of the correct damping factor to match the TC you use.
Too true, this started out to be just an antenna feed issue.
and it sounded like Said wanted to keep it simple.
I did not know this was going to be a Phase face
***
- Original Message -
From: Magnus Danielson mag...@rubidium.dyndns.org
To: WarrenS warrensjmail-...@yahoo.com; Discussion of precise time and
frequency measurement time-nuts@febo.com
Sent: Monday, November 23, 2009 4:06 PM
Subject: Re: [time-nuts] Thunderbolt reception problems
WarrenS wrote
Said
changing the AMU thresholds to 2.0 fixed the problem,
If 3 was not working, you should be able to go lower than 2, likely 1.0 to 1.5
will be better yet.
The way I tell is using Lady Heather, if there are satellites signals with
levels between 20 and 30 dBc
with good ACCUs that are
If you needed to lower your AMU limit from 4 to 2, you are feeding the
Thunderbolt a signal level below the intended levels.
True, You MAY be feeding it a signal that is below what the cell site
recommended High gain outdoor antenna will give it.
But any conclusion past that sounds like pure
Mark
Sounds like the same problem I had when I had the AMU set TOO high. ( I don't
think it can be set with LH, Need Tboltmon to change it)
I have not seen the condition that you describe where the Tbolt will switch
satellites just because it has found a better one. (I don't think that
-
From: Magnus Danielson mag...@rubidium.dyndns.org
To: WarrenS warrensjmail-...@yahoo.com; Discussion of precise time and
frequency measurement time-nuts@febo.com
Sent: Sunday, November 22, 2009 5:03 PM
Subject: Re: [time-nuts] Thunderbolt reception problems
Warren,
WarrenS wrote:
If you
Maybe something too basic many too say, but did you lower the Tbolts signal
level mask AMU setting?
Default is 3, set to 1 or 2 so that it will accept lower level signals
- Original Message -
From: saidj...@aol.com
To: time-nuts@febo.com
Sent: Saturday, November 21, 2009 11:40 AM
I gather from your referenced web page that it seems that a
higher damping number was better. Is this a correct assumption ?
Well Not exactly, It depends on the type and source of the noise error.
The simple answer is that the default damping setting of 1.2 on the Tbolt
is a good compromise
The only downside of the longer time constant seems
to be that the PPS seems to move around more, ...
Because LH's Plots and Adevs are based on the difference of the OXCO and the
Tbolts own
internal filtered GPS signal and not on an external quiet Reference as is the
more common practice,
Does the longer time constant actually make a better frequency standard
Depends how much of a hurry you are in to measure your freq.
A longer TC on the TBolt makes it have a lot less Phase noise
and Freq noise at low Tau and gate times under 100 seconds.
At longer times of 1000 sec + it does
Yes, once I'd enabled the oscillator graph (in LH) and it virtually
obliterated
everything else I could see why it was normally off:-)
If you then do g o 100 Rtn and z o 150 Rtn that fixes that issue and
make the Osc plot very useful.
..
I'm seeing all the plots other than the frequency deviation.
Osc plot defaults to off,
g o turns in on
Push spare bar for the help screen
ws
*
I've been running the Windows version of Lady Heather tp make some
comparisons between Thunderbolts and Mini-Ts, she cracks her whip
After
g o Rtn to turn the Osc Freq plot on
Can set the plot scale factors for better readability
so that the Osc freq plot does not obscure the other plots:
m o Esc 100 Rtn Sets Osc Freq to 100 ppt/div
m p Esc 10 RtnSet Phase PPS to 10 ns/div
Another way to find the 'Dac Gain' that does not take any external Test
instruments,
Just Lady Heather or the TboltMon S/W program
Part of Original Message -
From: WB6BNQ
12) Make sure the Dac gain is correct, mine is -3.4, not the -5Hz/
volt default
How did you determine
John
I have had my TAPR Tbolt for a couple of months now so my sample size of one
and experience is rather limited.
I have found MANY reasons why my unit did and still does sometimes behave like
yours.
Sorry for the long answer to your long post, But
There is NO single one item that magically
Bill
- Original Message -
From: WB6BNQ
WarrenS wrote:
8) Do not put any pressure on the case top or bottom, put some rubber feet
under it in the 4 corners.
What do you mean by pressure ? Can you explain the pressure issue ?
If you squeeze the case or set something on top
the comments and feedback
ws
***
WarrenS wrote:
ws reply to Bruce's comments
That calibration is linear over than a 1 Hz (1e-7) offset range.
Whilst that may be true for your OCXO, this is certainly
not true for every ocxo one may wish to measure
John
Thanks, helpful and constructive points,
I'll try and comment on them all.
Ordinarily two oscillators won't track that well in
response to shared environmental conditions alone.
And I'm well aware of that.
I started by measuring their interactions, each both on their own independent
.
Are we having Fun now?
ws
**
- Original Message -
From: Bruce Griffiths bruce.griffi...@xtra.co.nz
To: WarrenS warrensjmail-...@yahoo.com; Discussion of precise time and
frequency measurement time-nuts@febo.com
Sent: Saturday, October 03, 2009 1:15 PM
Subject: Re: [time-nuts
can be
phase locked to the other.
This isn't always possible, for example, if one wishes to evaluate the
stability of an offset oscillator this technique cant be used.
Bruce
*
WarrenS wrote:
I have been using a simple low cost, high performance alternate solution
to the standard Dual
noise
level.
ws
***
From: Bruce Griffiths bruce.griffi...@xtra.co.nz
WarrenS wrote:
Bruce
Yes, there are a few disadvantages using this simple low
cost configuration along with all of its advantages.
You can not get everything for nothing, but you can get
higher
and Osc's
internal EFC offset.
The EFC range being used during a measurement period is typically less than
1/1000 of its range.
ws
- Original Message -
From: Bruce Griffiths bruce.griffi...@xtra.co.nz
To: WarrenS warrensjmail-...@yahoo.com; Discussion of precise time
tau expert's advice sought
Basically my question is that is the correct bandwidth to use when taking 1 sec
and above tau data?
What I want to know is how to record raw 1 second phase data to use for
calculating 1 sec and above tau.
Should I including in the data the results of every high freq
Nigel
Um is right,
One of us is missing something, I wonder which one, I think I know.
He has a good bypass cap across all that, The RF is not going to see the diodes.
ws
---
Um
Not really a very good idea, we're talking about two silicon diodes in
series with
I should of added
Yes, It's normal for phase measurement to be 3 counts OR anything else
depending on the frequency you are measuring.
The unit measures Time delay to 1ns, and calculates Phase which can be any
number depending on Freq.
Use Time interval not phase to see what the noise is.
TBolt Nuts
To keep My TBolt's temperature constant so that the environment has minimal
effect on it,
I use an aquarium temperature controller (modified to have low hysteresis)
connected to a low wattage light bulb, placed in a box with the TBolt.
It works OK and keeps the TBolt's temperature
. Even put a little LED on it to indicate
state.
Don
WarrenS
TBolt Nuts
To keep My TBolt's temperature constant so that the environment has
minimal effect on it,
I use an aquarium temperature controller (modified to have low hysteresis)
connected to a low wattage light bulb, placed in a box
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