Re: [time-nuts] Measuring receiver...

[Don Latham]

Yes, very simple for people, very difficult for “machinery”. 
Don
> On Jun 21, 2016, at 7:01 PM, William H. Fite  wrote:
> 
> In the days of my misspent youth, I worked as a telegrapher (one of the
> very last) for a Norwegian shipping line. We sent and received both
> Norwegian and English though few of us were bilingual. Between ships and
> shore stations, there were about forty of us and we all could recognize
> each other's "fists" with near-perfect accuracy. This is not difficult,
> gentlemen, and does not require any esoteric signal analysis. Transmitters
> would be a different story.
> 
> Bill KJ4SLP
> 
> 
> 
> On Tuesday, June 21, 2016, John Ackermann N8UR  > wrote:
> 
>> I've seen references that at least by the latter part of WW2 oscillographs
>> were being used to identify transmitters and/or ops.  It should be possible
>> to deduce chirp, rise time, fall time of signals, all of which characterize
>> the transmitter, as well as element spacing and other characteristics that
>> help identify the operator, from oscilloscope snapshots of the demodulated
>> audio at various sweep speeds.
>> 
>> 
>>> On Jun 21, 2016, at 7:02 PM, Alan Melia > > wrote:
>>> 
>>> TX "fingerprinting" in WWII
>>> You seem to be forgetting that there were very few of the sophisticated
>> digital timing systems were available 75 years ago. Traffic analysis was
>> started early in 1938 or even before. By 1939 we knew all the nets used in
>> Europe and had "Y" ( a corruption of WI, Wireless Intercept )operators
>> monitoring the nets. Many of these were amateurs and they were allocated to
>> specific nets and followed them around as they moved. They became very
>> familiar with the "accents" of operators on their nets, and particularly
>> before 1939 security procedures were very lax and "chatting"
>> common-place.but it was all aural.
>>> 
>>> I suspect serious transmitter parameter logging was not done before the
>> cold war when spectrum analysers, or at least pan-adapters became more
>> readily available. To keep a little OnTopic .you would have difficulty
>> doing this with a BC-221.!! :-)) A crystal clock of this period was at
>> least one fully utilised 6foot 19inch rack (there is one at Grenwich.)
>>> Alan
>>> G3NYK
>>> 
>>> 
>>> Alan
>>> G3NYK
>>> 
>>> - Original Message - From: "jimlux" > >
>>> To: >
>>> Sent: Tuesday, June 21, 2016 10:02 PM
>>> Subject: Re: [time-nuts] Measuring receiver...
>>> 
>>> 
> On 6/21/16 11:28 AM, Brooke Clarke wrote:
> Hi:
> 
> During W.W.II there were secret methods of "fingerprinting" radio
> transmitters and separately the operators.
> I suspect the transmitter fingerprinting involved things like frequency
> accuracy, stability, CW rise and decay time, &Etc. For the operator
>> some
> from of statistics on the timings associated with sending Morse Code.
> But. . .  I haven't seen any papers describing this.  Can anyone point
> me to a paper on this?
 For "human controlled" stuff, e.g. recognizing someone's "fist",
>> there's a huge literature out there on biometric identification looking at
>> things like keyboard and mouse click timing - the timing requirements are
>> pretty slack, and hardly time-nuts level, unless you're looking to do it
>> with mechanical devices constructed from spare twigs and strands of kelp.
 
 There have been a variety of schemes for recognizing individual radios
>> by looking at the frequency vs time as they start up. Likewise, it's pretty
>> easy to distinguish radar magnetrons from each other.  Not a lot of papers
>> about this, but you'll see it in advertising literature, or occasionally in
>> conference pubs (although I can't think of any off hand).  There was
>> someone selling a repeater access control system that was based on the
>> transmitter fingerprint.
 
 But the real reason why you don't see any publications is that this
>> stuff is pretty classic signals intelligence (SIGINT or MASINT) and it is
>> still being used, and is all classified. You're not relying on Betty the
>> receiver operator to recognize the characteristic chirp as the agent's
>> radio is keyed, it's all done by computer now, but the basic idea is the
>> same.  And as with most of this stuff, the basics are well known, but the
>> practical details are not, or, at least, are the proprietary secret sauce
>> in any practical system. (In a significant understatement, Dixon, in
>> "Spread Spectrum Systems" makes some comment about how synch acquisition is
>> the difficult part and won't be described in the book)
 
 You might look at the unclassified proceedings of conferences like
>> MILCOM and find something.  Googling with MASINT might also help.
 
 ___
 time-nuts mailing list -- time-nuts@febo.com 
 To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
 and follow the instructions there.
>

Re: [time-nuts] Measuring receiver...

[William H. Fite]

In the days of my misspent youth, I worked as a telegrapher (one of the
very last) for a Norwegian shipping line. We sent and received both
Norwegian and English though few of us were bilingual. Between ships and
shore stations, there were about forty of us and we all could recognize
each other's "fists" with near-perfect accuracy. This is not difficult,
gentlemen, and does not require any esoteric signal analysis. Transmitters
would be a different story.

Bill KJ4SLP



On Tuesday, June 21, 2016, John Ackermann N8UR  wrote:

> I've seen references that at least by the latter part of WW2 oscillographs
> were being used to identify transmitters and/or ops.  It should be possible
> to deduce chirp, rise time, fall time of signals, all of which characterize
> the transmitter, as well as element spacing and other characteristics that
> help identify the operator, from oscilloscope snapshots of the demodulated
> audio at various sweep speeds.
>
>
> > On Jun 21, 2016, at 7:02 PM, Alan Melia  > wrote:
> >
> > TX "fingerprinting" in WWII
> > You seem to be forgetting that there were very few of the sophisticated
> digital timing systems were available 75 years ago. Traffic analysis was
> started early in 1938 or even before. By 1939 we knew all the nets used in
> Europe and had "Y" ( a corruption of WI, Wireless Intercept )operators
> monitoring the nets. Many of these were amateurs and they were allocated to
> specific nets and followed them around as they moved. They became very
> familiar with the "accents" of operators on their nets, and particularly
> before 1939 security procedures were very lax and "chatting"
> common-place.but it was all aural.
> >
> > I suspect serious transmitter parameter logging was not done before the
> cold war when spectrum analysers, or at least pan-adapters became more
> readily available. To keep a little OnTopic .you would have difficulty
> doing this with a BC-221.!! :-)) A crystal clock of this period was at
> least one fully utilised 6foot 19inch rack (there is one at Grenwich.)
> > Alan
> > G3NYK
> >
> >
> > Alan
> > G3NYK
> >
> > - Original Message - From: "jimlux"  >
> > To: >
> > Sent: Tuesday, June 21, 2016 10:02 PM
> > Subject: Re: [time-nuts] Measuring receiver...
> >
> >
> >>> On 6/21/16 11:28 AM, Brooke Clarke wrote:
> >>> Hi:
> >>>
> >>> During W.W.II there were secret methods of "fingerprinting" radio
> >>> transmitters and separately the operators.
> >>> I suspect the transmitter fingerprinting involved things like frequency
> >>> accuracy, stability, CW rise and decay time, &Etc. For the operator
> some
> >>> from of statistics on the timings associated with sending Morse Code.
> >>> But. . .  I haven't seen any papers describing this.  Can anyone point
> >>> me to a paper on this?
> >> For "human controlled" stuff, e.g. recognizing someone's "fist",
> there's a huge literature out there on biometric identification looking at
> things like keyboard and mouse click timing - the timing requirements are
> pretty slack, and hardly time-nuts level, unless you're looking to do it
> with mechanical devices constructed from spare twigs and strands of kelp.
> >>
> >> There have been a variety of schemes for recognizing individual radios
> by looking at the frequency vs time as they start up. Likewise, it's pretty
> easy to distinguish radar magnetrons from each other.  Not a lot of papers
> about this, but you'll see it in advertising literature, or occasionally in
> conference pubs (although I can't think of any off hand).  There was
> someone selling a repeater access control system that was based on the
> transmitter fingerprint.
> >>
> >> But the real reason why you don't see any publications is that this
> stuff is pretty classic signals intelligence (SIGINT or MASINT) and it is
> still being used, and is all classified. You're not relying on Betty the
> receiver operator to recognize the characteristic chirp as the agent's
> radio is keyed, it's all done by computer now, but the basic idea is the
> same.  And as with most of this stuff, the basics are well known, but the
> practical details are not, or, at least, are the proprietary secret sauce
> in any practical system. (In a significant understatement, Dixon, in
> "Spread Spectrum Systems" makes some comment about how synch acquisition is
> the difficult part and won't be described in the book)
> >>
> >> You might look at the unclassified proceedings of conferences like
> MILCOM and find something.  Googling with MASINT might also help.
> >>
> >> ___
> >> time-nuts mailing list -- time-nuts@febo.com 
> >> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> >> and follow the instructions there.
> >
> > ___
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> > To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> > and follow the instructions there.
>
> __

Re: [time-nuts] Measuring receiver...

[Brooke Clarke]

Hi Alan:

I've read that prior to 7 Dec 1941 we were able to identify both radio operators (by their "fist") and radios by serial 
number.  So we could tell that Joe was not on his usual ship and by using DF we knew where that ship was located.


--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
The lesser of evils is still evil.

 Original Message 

TX "fingerprinting" in WWII
You seem to be forgetting that there were very few of the sophisticated digital timing systems were available 75 years 
ago. Traffic analysis was started early in 1938 or even before. By 1939 we knew all the nets used in Europe and had 
"Y" ( a corruption of WI, Wireless Intercept )operators monitoring the nets. Many of these were amateurs and they were 
allocated to specific nets and followed them around as they moved. They became very familiar with the "accents" of 
operators on their nets, and particularly before 1939 security procedures were very lax and "chatting" 
common-place.but it was all aural.


I suspect serious transmitter parameter logging was not done before the cold war when spectrum analysers, or at least 
pan-adapters became more readily available. To keep a little OnTopic .you would have difficulty doing this with a 
BC-221.!! :-)) A crystal clock of this period was at least one fully utilised 6foot 19inch rack (there is one at 
Grenwich.)

Alan
G3NYK


Alan
G3NYK

- Original Message - From: "jimlux" 
To: 
Sent: Tuesday, June 21, 2016 10:02 PM
Subject: Re: [time-nuts] Measuring receiver...



On 6/21/16 11:28 AM, Brooke Clarke wrote:

Hi:

During W.W.II there were secret methods of "fingerprinting" radio
transmitters and separately the operators.
I suspect the transmitter fingerprinting involved things like frequency
accuracy, stability, CW rise and decay time, &Etc. For the operator some
from of statistics on the timings associated with sending Morse Code.
But. . .  I haven't seen any papers describing this.  Can anyone point
me to a paper on this?

For "human controlled" stuff, e.g. recognizing someone's "fist", there's a huge literature out there on biometric 
identification looking at things like keyboard and mouse click timing - the timing requirements are pretty slack, and 
hardly time-nuts level, unless you're looking to do it with mechanical devices constructed from spare twigs and 
strands of kelp.


There have been a variety of schemes for recognizing individual radios by looking at the frequency vs time as they 
start up. Likewise, it's pretty easy to distinguish radar magnetrons from each other.  Not a lot of papers about 
this, but you'll see it in advertising literature, or occasionally in conference pubs (although I can't think of any 
off hand).  There was someone selling a repeater access control system that was based on the transmitter fingerprint.


But the real reason why you don't see any publications is that this stuff is pretty classic signals intelligence 
(SIGINT or MASINT) and it is still being used, and is all classified. You're not relying on Betty the receiver 
operator to recognize the characteristic chirp as the agent's radio is keyed, it's all done by computer now, but the 
basic idea is the same.  And as with most of this stuff, the basics are well known, but the practical details are 
not, or, at least, are the proprietary secret sauce in any practical system. (In a significant understatement, Dixon, 
in "Spread Spectrum Systems" makes some comment about how synch acquisition is the difficult part and won't be 
described in the book)


You might look at the unclassified proceedings of conferences like MILCOM and find something.  Googling with MASINT 
might also help.


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Re: [time-nuts] Measuring receiver...

[John Ackermann N8UR]

I've seen references that at least by the latter part of WW2 oscillographs were 
being used to identify transmitters and/or ops.  It should be possible to 
deduce chirp, rise time, fall time of signals, all of which characterize the 
transmitter, as well as element spacing and other characteristics that help 
identify the operator, from oscilloscope snapshots of the demodulated audio at 
various sweep speeds.


> On Jun 21, 2016, at 7:02 PM, Alan Melia  wrote:
> 
> TX "fingerprinting" in WWII
> You seem to be forgetting that there were very few of the sophisticated 
> digital timing systems were available 75 years ago. Traffic analysis was 
> started early in 1938 or even before. By 1939 we knew all the nets used in 
> Europe and had "Y" ( a corruption of WI, Wireless Intercept )operators 
> monitoring the nets. Many of these were amateurs and they were allocated to 
> specific nets and followed them around as they moved. They became very 
> familiar with the "accents" of operators on their nets, and particularly 
> before 1939 security procedures were very lax and "chatting" 
> common-place.but it was all aural.
> 
> I suspect serious transmitter parameter logging was not done before the cold 
> war when spectrum analysers, or at least pan-adapters became more readily 
> available. To keep a little OnTopic .you would have difficulty doing this 
> with a BC-221.!! :-)) A crystal clock of this period was at least one fully 
> utilised 6foot 19inch rack (there is one at Grenwich.)
> Alan
> G3NYK
> 
> 
> Alan
> G3NYK
> 
> - Original Message - From: "jimlux" 
> To: 
> Sent: Tuesday, June 21, 2016 10:02 PM
> Subject: Re: [time-nuts] Measuring receiver...
> 
> 
>>> On 6/21/16 11:28 AM, Brooke Clarke wrote:
>>> Hi:
>>> 
>>> During W.W.II there were secret methods of "fingerprinting" radio
>>> transmitters and separately the operators.
>>> I suspect the transmitter fingerprinting involved things like frequency
>>> accuracy, stability, CW rise and decay time, &Etc. For the operator some
>>> from of statistics on the timings associated with sending Morse Code.
>>> But. . .  I haven't seen any papers describing this.  Can anyone point
>>> me to a paper on this?
>> For "human controlled" stuff, e.g. recognizing someone's "fist", there's a 
>> huge literature out there on biometric identification looking at things like 
>> keyboard and mouse click timing - the timing requirements are pretty slack, 
>> and hardly time-nuts level, unless you're looking to do it with mechanical 
>> devices constructed from spare twigs and strands of kelp.
>> 
>> There have been a variety of schemes for recognizing individual radios by 
>> looking at the frequency vs time as they start up. Likewise, it's pretty 
>> easy to distinguish radar magnetrons from each other.  Not a lot of papers 
>> about this, but you'll see it in advertising literature, or occasionally in 
>> conference pubs (although I can't think of any off hand).  There was someone 
>> selling a repeater access control system that was based on the transmitter 
>> fingerprint.
>> 
>> But the real reason why you don't see any publications is that this stuff is 
>> pretty classic signals intelligence (SIGINT or MASINT) and it is still being 
>> used, and is all classified. You're not relying on Betty the receiver 
>> operator to recognize the characteristic chirp as the agent's radio is 
>> keyed, it's all done by computer now, but the basic idea is the same.  And 
>> as with most of this stuff, the basics are well known, but the practical 
>> details are not, or, at least, are the proprietary secret sauce in any 
>> practical system. (In a significant understatement, Dixon, in "Spread 
>> Spectrum Systems" makes some comment about how synch acquisition is the 
>> difficult part and won't be described in the book)
>> 
>> You might look at the unclassified proceedings of conferences like MILCOM 
>> and find something.  Googling with MASINT might also help.
>> 
>> ___
>> time-nuts mailing list -- time-nuts@febo.com
>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
> 
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> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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Re: [time-nuts] Measuring receiver...

[Graham / KE9H]

This is heavily used in cellular system security and cellular unit
identification and tracking.
Do a google search on patents using the the term "RF fingerprinting" and
you will get quite a few hits.  Mostly recent application to cellular
systems.  You might look at the prior art listings and see if they take you
back somewhere.  Although unlikely any classified methods were patented.

--- Graham

==

On Tue, Jun 21, 2016 at 4:02 PM, jimlux  wrote:

> On 6/21/16 11:28 AM, Brooke Clarke wrote:
>
>> Hi:
>>
>> During W.W.II there were secret methods of "fingerprinting" radio
>> transmitters and separately the operators.
>> I suspect the transmitter fingerprinting involved things like frequency
>> accuracy, stability, CW rise and decay time, &Etc. For the operator some
>> from of statistics on the timings associated with sending Morse Code.
>> But. . .  I haven't seen any papers describing this.  Can anyone point
>> me to a paper on this?
>>
>> For "human controlled" stuff, e.g. recognizing someone's "fist", there's
> a huge literature out there on biometric identification looking at things
> like keyboard and mouse click timing - the timing requirements are pretty
> slack, and hardly time-nuts level, unless you're looking to do it with
> mechanical devices constructed from spare twigs and strands of kelp.
>
> There have been a variety of schemes for recognizing individual radios by
> looking at the frequency vs time as they start up. Likewise, it's pretty
> easy to distinguish radar magnetrons from each other.  Not a lot of papers
> about this, but you'll see it in advertising literature, or occasionally in
> conference pubs (although I can't think of any off hand).  There was
> someone selling a repeater access control system that was based on the
> transmitter fingerprint.
>
> But the real reason why you don't see any publications is that this stuff
> is pretty classic signals intelligence (SIGINT or MASINT) and it is still
> being used, and is all classified. You're not relying on Betty the receiver
> operator to recognize the characteristic chirp as the agent's radio is
> keyed, it's all done by computer now, but the basic idea is the same.  And
> as with most of this stuff, the basics are well known, but the practical
> details are not, or, at least, are the proprietary secret sauce in any
> practical system. (In a significant understatement, Dixon, in "Spread
> Spectrum Systems" makes some comment about how synch acquisition is the
> difficult part and won't be described in the book)
>
> You might look at the unclassified proceedings of conferences like MILCOM
> and find something.  Googling with MASINT might also help.
>
>
> ___
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
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Re: [time-nuts] Measuring receiver...

[Alan Melia]

TX "fingerprinting" in WWII
You seem to be forgetting that there were very few of the sophisticated 
digital timing systems were available 75 years ago. Traffic analysis was 
started early in 1938 or even before. By 1939 we knew all the nets used in 
Europe and had "Y" ( a corruption of WI, Wireless Intercept )operators 
monitoring the nets. Many of these were amateurs and they were allocated to 
specific nets and followed them around as they moved. They became very 
familiar with the "accents" of operators on their nets, and particularly 
before 1939 security procedures were very lax and "chatting" 
common-place.but it was all aural.


I suspect serious transmitter parameter logging was not done before the cold 
war when spectrum analysers, or at least pan-adapters became more readily 
available. To keep a little OnTopic .you would have difficulty doing 
this with a BC-221.!! :-)) A crystal clock of this period was at least one 
fully utilised 6foot 19inch rack (there is one at Grenwich.)

Alan
G3NYK


Alan
G3NYK

- Original Message - 
From: "jimlux" 

To: 
Sent: Tuesday, June 21, 2016 10:02 PM
Subject: Re: [time-nuts] Measuring receiver...



On 6/21/16 11:28 AM, Brooke Clarke wrote:

Hi:

During W.W.II there were secret methods of "fingerprinting" radio
transmitters and separately the operators.
I suspect the transmitter fingerprinting involved things like frequency
accuracy, stability, CW rise and decay time, &Etc. For the operator some
from of statistics on the timings associated with sending Morse Code.
But. . .  I haven't seen any papers describing this.  Can anyone point
me to a paper on this?

For "human controlled" stuff, e.g. recognizing someone's "fist", there's a 
huge literature out there on biometric identification looking at things 
like keyboard and mouse click timing - the timing requirements are pretty 
slack, and hardly time-nuts level, unless you're looking to do it with 
mechanical devices constructed from spare twigs and strands of kelp.


There have been a variety of schemes for recognizing individual radios by 
looking at the frequency vs time as they start up. Likewise, it's pretty 
easy to distinguish radar magnetrons from each other.  Not a lot of papers 
about this, but you'll see it in advertising literature, or occasionally 
in conference pubs (although I can't think of any off hand).  There was 
someone selling a repeater access control system that was based on the 
transmitter fingerprint.


But the real reason why you don't see any publications is that this stuff 
is pretty classic signals intelligence (SIGINT or MASINT) and it is still 
being used, and is all classified. You're not relying on Betty the 
receiver operator to recognize the characteristic chirp as the agent's 
radio is keyed, it's all done by computer now, but the basic idea is the 
same.  And as with most of this stuff, the basics are well known, but the 
practical details are not, or, at least, are the proprietary secret sauce 
in any practical system. (In a significant understatement, Dixon, in 
"Spread Spectrum Systems" makes some comment about how synch acquisition 
is the difficult part and won't be described in the book)


You might look at the unclassified proceedings of conferences like MILCOM 
and find something.  Googling with MASINT might also help.


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Re: [time-nuts] Pages on 5650-option-58

[Peter Reilley]

Jim;

I found this;

https://www.febo.com/pipermail/time-nuts/2008-June/031663.html

and this;

http://www.leapsecond.com/museum/fei5650a/


Pete.


On 6/21/2016 1:02 PM, James Robbins wrote:

Hello Bill,

  


I was reading an old note by you on Time-Nuts (April 7, 2013) where you
refer to a .zip file of materials on the 5650 rubidium oscillators.  There
was a link to the zip folder

(http://pages.suddenlink.net/stevewingate/cryptic1/for alec on
5650-option-58.zip
 ) which doesn't work any longer.  Would you have an alternative
link to the material.  I am soing some work with FE-5650A and FE-5658A
oscillators.

  


Many thanks.

  


Jim Robbins

N1JR

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Re: [time-nuts] Measuring receiver...

[jimlux]

On 6/21/16 11:28 AM, Brooke Clarke wrote:

Hi:

During W.W.II there were secret methods of "fingerprinting" radio
transmitters and separately the operators.
I suspect the transmitter fingerprinting involved things like frequency
accuracy, stability, CW rise and decay time, &Etc. For the operator some
from of statistics on the timings associated with sending Morse Code.
But. . .  I haven't seen any papers describing this.  Can anyone point
me to a paper on this?

For "human controlled" stuff, e.g. recognizing someone's "fist", there's 
a huge literature out there on biometric identification looking at 
things like keyboard and mouse click timing - the timing requirements 
are pretty slack, and hardly time-nuts level, unless you're looking to 
do it with mechanical devices constructed from spare twigs and strands 
of kelp.


There have been a variety of schemes for recognizing individual radios 
by looking at the frequency vs time as they start up. Likewise, it's 
pretty easy to distinguish radar magnetrons from each other.  Not a lot 
of papers about this, but you'll see it in advertising literature, or 
occasionally in conference pubs (although I can't think of any off 
hand).  There was someone selling a repeater access control system that 
was based on the transmitter fingerprint.


But the real reason why you don't see any publications is that this 
stuff is pretty classic signals intelligence (SIGINT or MASINT) and it 
is still being used, and is all classified. You're not relying on Betty 
the receiver operator to recognize the characteristic chirp as the 
agent's radio is keyed, it's all done by computer now, but the basic 
idea is the same.  And as with most of this stuff, the basics are well 
known, but the practical details are not, or, at least, are the 
proprietary secret sauce in any practical system. (In a significant 
understatement, Dixon, in "Spread Spectrum Systems" makes some comment 
about how synch acquisition is the difficult part and won't be described 
in the book)


You might look at the unclassified proceedings of conferences like 
MILCOM and find something.  Googling with MASINT might also help.


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Re: [time-nuts] Measuring receiver...

[Brooke Clarke]

Hi:

During W.W.II there were secret methods of "fingerprinting" radio transmitters 
and separately the operators.
I suspect the transmitter fingerprinting involved things like frequency accuracy, stability, CW rise and decay time, 
&Etc. For the operator some from of statistics on the timings associated with sending Morse Code.  But. . .  I haven't 
seen any papers describing this.  Can anyone point me to a paper on this?


--
Have Fun,

Brooke Clarke, N6GCE
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
The lesser of evils is still evil.

 Original Message 

Nick,

Welcome to the world of FMT-Nuttery where we strive to make absurdly accurate 
off-air frequency measurements.

I regularly participate in the FMT's.  The "measuring receiver" I use is a HP-3586B "Selective Level Meter".  While 
the 3586 series of receivers will only give you 0.1 Hz resolution, there are simple methods to use them to get down to 
1 mHz (milliHertz) resolution, or better.  You'll quickly find out that you're limited by propagation between the FMT 
transmitter and your receive location.


Rather than go into a long dissertation here on how to do this, here's a link to the write-up for my preferred FMT 
Methodology - K6OQK FMT Methodology.


See:  http://www.k5cm.com/k6oqk%20fmt%20new.htm

You're probably already familiar with Connie, K5CM's website for all things FMT, but in case you're not, take a look 
at: www.k5cm.com


I'll be glad to answer any questions you have.  You can either ask here or send 
me a direct e-mail at: b...@att.net.

Burt, K6OQK


From: Nick Sayer 

I'm considering taking a shot at the next ARRL frequency measurement contest.

The assumption going in is that the signal is CW, with at least a half minute or so of just solid "on" at one point or 
another and that reception is reasonably good.


I've got a good TIA and excellent references, but that's the easy part, it seems to me. It seems to me that what I 
really need to do is make a synthesized heterodyne receiver that can present an accurately tuned RF band pass - say, 
10 kHz wide with the synthesizer set for
5 kHz steps - to the TIA, with some manually tunable high-pass and low-pass filtering to isolate the signal of 
interest. If the mixer got its LO from a synthesizer with a GPSDO reference, it seems to me that you could then 
measure the frequency of the signal of interest (now an audio frequency, so you can listen to it too) with the TIA 
(also getting the GPSDO reference) and then do simple math to arrive at the actual RF frequency.


Anybody have any thoughts?

Burt I. Weiner Associates
Broadcast Technical Services
Glendale, California  U.S.A.
b...@att.net
www.biwa.cc
K6OQK
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Re: [time-nuts] Pages on 5650-option-58

[James Robbins]

Hello Bill,

 

I was reading an old note by you on Time-Nuts (April 7, 2013) where you
refer to a .zip file of materials on the 5650 rubidium oscillators.  There
was a link to the zip folder 

(http://pages.suddenlink.net/stevewingate/cryptic1/for alec on
5650-option-58.zip
 ) which doesn't work any longer.  Would you have an alternative
link to the material.  I am soing some work with FE-5650A and FE-5658A
oscillators.

 

Many thanks.

 

Jim Robbins

N1JR

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[time-nuts] Measuring receiver...

[Burt I. Weiner]

Nick,

Welcome to the world of FMT-Nuttery where we strive to make absurdly 
accurate off-air frequency measurements.


I regularly participate in the FMT's.  The "measuring receiver" I use 
is a HP-3586B "Selective Level Meter".  While the 3586 series of 
receivers will only give you 0.1 Hz resolution, there are simple 
methods to use them to get down to 1 mHz (milliHertz) resolution, or 
better.  You'll quickly find out that you're limited by propagation 
between the FMT transmitter and your receive location.


Rather than go into a long dissertation here on how to do this, 
here's a link to the write-up for my preferred FMT Methodology - 
K6OQK FMT Methodology.


See:  http://www.k5cm.com/k6oqk%20fmt%20new.htm

You're probably already familiar with Connie, K5CM's website for all 
things FMT, but in case you're not, take a look at:  www.k5cm.com


I'll be glad to answer any questions you have.  You can either ask 
here or send me a direct e-mail at: b...@att.net.


Burt, K6OQK


From: Nick Sayer 

I'm considering taking a shot at the next ARRL frequency measurement contest.

The assumption going in is that the signal is CW, with at least a 
half minute or so of just solid "on" at one point or another and that 
reception is reasonably good.


I've got a good TIA and excellent references, but that's the easy 
part, it seems to me. It seems to me that what I really need to do is 
make a synthesized heterodyne receiver that can present an accurately 
tuned RF band pass - say, 10 kHz wide with the synthesizer set for
5 kHz steps - to the TIA, with some manually tunable high-pass and 
low-pass filtering to isolate the signal of interest. If the mixer 
got its LO from a synthesizer with a GPSDO reference, it seems to me 
that you could then measure the frequency of the signal of interest 
(now an audio frequency, so you can listen to it too) with the TIA 
(also getting the GPSDO reference) and then do simple math to arrive 
at the actual RF frequency.


Anybody have any thoughts?

Burt I. Weiner Associates
Broadcast Technical Services
Glendale, California  U.S.A.
b...@att.net
www.biwa.cc
K6OQK 


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