Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old November 10th 05, 10:06 AM
ml
 
Posts: n/a
Default fmt

hi

I noticed the below lately and wonder, being new at this ... how one
would measure it?

is their a step by step guide or just a specific instrument(s) you need

I'd love to learn and try it, but didn't see any posted
''instructions''...
any help appreciated


m


partially cut from the arrl's email
"Returning to the airwaves November 17 at 0245 UTC (Wednesday,
November 16 in US time zones), the 2005 ARRL Frequency Measuring
Test (FMT) once again will call on participants to measure the
frequency of an audio tone modulating the carrier.

''Measuring the tone frequency, as opposed to that of the carrier,
reinforces the understanding of the relationship between carrier
frequency and the actual components of a transmitted signal,''
Engineer and ARRL Contributing Editor Ward Silver, N0AX, says in
''Tune In the 2005 Frequency Measuring Test,'' in November QST (p
54),...www.arrl.org/w1aw/fmt/2005/05fmtsilver.pdf. ''With the carrier
largely suppressed for SSB signals, only the sideband components
remain. A single modulating tone results in a single transmitted
component.'' But, Silver notes, the frequency of the absent carrier
is what the operator sees on the radio's display.

The FMT signals will emanate from Maxim Memorial Station W1AW this
year on 160, 80 and 40 meters. The 20-meter transmission has been
dropped for 2005 because of the generally poor conditions during
evening hours on that band. The frequencies will be 1855, 3990 and
7290 kHz, and all transmissions will be on lower sideband (LSB). The
FMT will replace the W1AW phone bulletin normally transmitted at
0245 UTC on November 17 (November 16 in US time zones).

Participants may utilize either direct or indirect techniques to
determine the tone frequency. ''Direct measurements assume a carrier
frequency and measure the audio tone frequency directly,'' Silver
explains. ''Indirect measurements obtain the transmitted frequency of
the tone component at RF, then compute the difference between the
published carrier frequency and measured frequency.''

Silver advises that since the W1AW exciters are independent units
and not fed with a single local oscillator, participants can expect
the measured tone frequency to differ slightly on each band.

The test itself will consist of three 60-second tone transmissions
on each band, followed by a station identification. The whole test
will run for about 15 minutes and will end with a station ID.

Submitted reports should include the time of reception and the tone
frequency. Those using an indirect measurement method should show
how they calculated the tone frequency. Participants also should
include name, call sign and location in their reports, and they may
submit separate reports for each band. A Certificate of
Participation is available to all entrants.
  #2   Report Post  
Old November 10th 05, 04:33 PM
Richard Clark
 
Posts: n/a
Default fmt

On Thu, 10 Nov 2005 10:06:56 GMT, ml wrote:
I'd love to learn and try it, but didn't see any posted
''instructions''...


Participants may utilize either direct or indirect techniques to
determine the tone frequency. ''Direct measurements assume a carrier
frequency and measure the audio tone frequency directly,'' Silver
explains. ''Indirect measurements obtain the transmitted frequency of
the tone component at RF, then compute the difference between the
published carrier frequency and measured frequency.''


Hi Myles,

You don't see instructions because you are supposed to work this out
for yourself and then report both your results and HOW YOU DID IT.

It should be a slam dunk with a PC sound card being run under an FFT.
However, the skill part is tuning the sideband (and then it remains
only the skill of reading the frequency setting of your rig - any
error is probably going to be there).

73's
Richard Clark, KB7QHC
  #3   Report Post  
Old November 10th 05, 11:12 PM
J. Mc Laughlin
 
Posts: n/a
Default fmt

Years ago, I was faculty advisor of a thesis containing a viable technique
for measuring the carrier of a SSB signal modulated by a human voice when
the carrier was nulled. The student's name, as well as I can remember, was
Day and his first name was something like Louis.

Should be a link to it somewhere.

The scheme took advantage of the nature of the human voice. It required one
to have the means to inject a carrier (which was measured by conventional
means) and to look at the recovered audio on a scope.

The old FMT had one measure CW signals. They were great fun.

73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:
"Richard Clark" wrote in message
...
On Thu, 10 Nov 2005 10:06:56 GMT, ml wrote:
I'd love to learn and try it, but didn't see any posted
''instructions''...


Participants may utilize either direct or indirect techniques to
determine the tone frequency. ''Direct measurements assume a carrier
frequency and measure the audio tone frequency directly,'' Silver
explains. ''Indirect measurements obtain the transmitted frequency of
the tone component at RF, then compute the difference between the
published carrier frequency and measured frequency.''


Hi Myles,

You don't see instructions because you are supposed to work this out
for yourself and then report both your results and HOW YOU DID IT.

It should be a slam dunk with a PC sound card being run under an FFT.
However, the skill part is tuning the sideband (and then it remains
only the skill of reading the frequency setting of your rig - any
error is probably going to be there).

73's
Richard Clark, KB7QHC



  #4   Report Post  
Old November 10th 05, 11:26 PM
J. Mc Laughlin
 
Posts: n/a
Default fmt

Here is the title and author's name:
A method for accurate receiver tuning and precise measurement of the carrier
frequency of voice-modulated, suppressed-carrier, single-sideband radio
signals
Day, Lucius Boyden.

I do not know where it might be read on the WEB. 73 Mac N8TT
--
J. Mc Laughlin; Michigan U.S.A.
Home:
"J. Mc Laughlin" wrote in message
...
Years ago, I was faculty advisor of a thesis containing a viable technique
for measuring the carrier of a SSB signal modulated by a human voice when
the carrier was nulled. The student's name, as well as I can remember,

was
Day and his first name was something like Louis.

Should be a link to it somewhere.

The scheme took advantage of the nature of the human voice. It required

one
to have the means to inject a carrier (which was measured by conventional
means) and to look at the recovered audio on a scope.

The old FMT had one measure CW signals. They were great fun.

73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:

"Richard Clark" wrote in message
...
On Thu, 10 Nov 2005 10:06:56 GMT, ml wrote:
I'd love to learn and try it, but didn't see any posted
''instructions''...


Participants may utilize either direct or indirect techniques to
determine the tone frequency. ''Direct measurements assume a carrier
frequency and measure the audio tone frequency directly,'' Silver
explains. ''Indirect measurements obtain the transmitted frequency of
the tone component at RF, then compute the difference between the
published carrier frequency and measured frequency.''


Hi Myles,

You don't see instructions because you are supposed to work this out
for yourself and then report both your results and HOW YOU DID IT.

It should be a slam dunk with a PC sound card being run under an FFT.
However, the skill part is tuning the sideband (and then it remains
only the skill of reading the frequency setting of your rig - any
error is probably going to be there).

73's
Richard Clark, KB7QHC





  #5   Report Post  
Old November 11th 05, 12:41 AM
Richard Clark
 
Posts: n/a
Default fmt

On Thu, 10 Nov 2005 18:26:38 -0500, "J. Mc Laughlin"
wrote:

Here is the title and author's name:
A method for accurate receiver tuning and precise measurement of the carrier
frequency of voice-modulated, suppressed-carrier, single-sideband radio
signals
Day, Lucius Boyden.

I do not know where it might be read on the WEB. 73 Mac N8TT


Hi Mac,

With a name like that, a search against it should have more success
than I have encountered (which is to say none). Wish I could have
done better.

73's
Richard Clark, KB7QHC


  #6   Report Post  
Old November 11th 05, 04:34 AM
J. Mc Laughlin
 
Posts: n/a
Default fmt

Dear Richard:
I too have given it a good try without much success. I think that I gave my
(paper) copy to our library long ago. It probably disappeared is one of
many purges. The Naval Postgraduate School indicates that they have two
paper copies.

I will try to remember details. The scheme worked.

It just occurred to me to check for a Radio Amateur license:
DAY JR, LUCIUS B, W5ZJZ (General)
10306 W IDAHO PL
LAKEWOOD, CO 80232-5019
His age is about right.

73, Mac N8TT
--
J. Mc Laughlin; Michigan U.S.A.
Home:
"Richard Clark" wrote in message
...
On Thu, 10 Nov 2005 18:26:38 -0500, "J. Mc Laughlin"
wrote:

Here is the title and author's name:
A method for accurate receiver tuning and precise measurement of the

carrier
frequency of voice-modulated, suppressed-carrier, single-sideband radio
signals
Day, Lucius Boyden.

I do not know where it might be read on the WEB. 73 Mac N8TT


Hi Mac,

With a name like that, a search against it should have more success
than I have encountered (which is to say none). Wish I could have
done better.

73's
Richard Clark, KB7QHC



  #7   Report Post  
Old November 11th 05, 01:26 AM
Jim Kelley
 
Posts: n/a
Default fmt



J. Mc Laughlin wrote:

Here is the title and author's name:
A method for accurate receiver tuning and precise measurement of the carrier
frequency of voice-modulated, suppressed-carrier, single-sideband radio
signals
Day, Lucius Boyden.

I do not know where it might be read on the WEB. 73 Mac N8TT
--
J. Mc Laughlin; Michigan U.S.A.
Home:


No hits in the UC library system, unfortunately.

jk

"J. Mc Laughlin" wrote in message
...

Years ago, I was faculty advisor of a thesis containing a viable technique
for measuring the carrier of a SSB signal modulated by a human voice when
the carrier was nulled. The student's name, as well as I can remember,


was

Day and his first name was something like Louis.

Should be a link to it somewhere.

The scheme took advantage of the nature of the human voice. It required


one

to have the means to inject a carrier (which was measured by conventional
means) and to look at the recovered audio on a scope.

The old FMT had one measure CW signals. They were great fun.

73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:

"Richard Clark" wrote in message
. ..

On Thu, 10 Nov 2005 10:06:56 GMT, ml wrote:

I'd love to learn and try it, but didn't see any posted
''instructions''...

Participants may utilize either direct or indirect techniques to
determine the tone frequency. ''Direct measurements assume a carrier
frequency and measure the audio tone frequency directly,'' Silver
explains. ''Indirect measurements obtain the transmitted frequency of
the tone component at RF, then compute the difference between the
published carrier frequency and measured frequency.''

Hi Myles,

You don't see instructions because you are supposed to work this out
for yourself and then report both your results and HOW YOU DID IT.

It should be a slam dunk with a PC sound card being run under an FFT.
However, the skill part is tuning the sideband (and then it remains
only the skill of reading the frequency setting of your rig - any
error is probably going to be there).

73's
Richard Clark, KB7QHC






  #9   Report Post  
Old November 12th 05, 03:04 AM
Nick Kennedy
 
Posts: n/a
Default fmt

"J. Mc Laughlin" wrote in message
...
Here is the title and author's name:
A method for accurate receiver tuning and precise measurement of the

carrier
frequency of voice-modulated, suppressed-carrier, single-sideband radio
signals
Day, Lucius Boyden.

I do not know where it might be read on the WEB. 73 Mac N8TT



It sounds similar to a recent article. I see that in the July/August QEX
there was an article called "A Blind Automatic Frequency Control Algorithm
for Single Sideband" by Geissinger. I can't find that issue, so don't know
it used Mr. Day's technique or not.

73--Nick, WA5BDU


Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT +1. The time now is 11:58 AM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017