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"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

Owen,
I believe you are mistaken. The carrier frequency is given. It will be
measured, in Newington, against either a cesium or rubidium standard (don't
remember which), but I don't know if it will actually be _controlled_ by the
standard.. It is only the audio tone which is the unknown.

73, Steve, K,9.D;C'I

"Owen Duffy" wrote in message
...
On Thu, 10 Nov 2005 10:06:56 GMT, ml wrote:

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

This looks like a guessing game / lottery to some extent, since no
information is given on the stability of either the virtual carrier or
the modulating tone (yet you are advised they both may vary) and the
time of measurement (an instant?) is part of the submitted data.

The winner using a sound scientific approach to measurement may
require luck to be not beaten by a less accurate, but closer answer at
some moment.

Owen

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.
--

OK, I found that QEX after much fuming and searching, under some recipes,
bills and phone books in the kitchen ...

Giessinger doesn't refer to Day's work. Among several references is one to
a work by Robert Dick in the Jan/Feb 1999 issue of QEX.

I won't try to paraphrase extensively, since I don't think I understand the
technique well enough to do it properly. It involves analyzing vowel
sounds, which have a fundamental and harmonics of predictable relative
amplitudes. I suppose you find the harmonic peaks and note the error in
their frequency relationship caused by mis-tuning, and there you go. Sounds
simple, if you don't have to actually do it. ;^)

I can see where it would be pretty straightforward (relatively) with music,
but doing this with voice is impressive to me.

Apparently similar techniques are now being used in high end rigs like the
IC-7800.

73--Nick, WA5BDU

"J. Mc Laughlin" wrote in message
...
Dear Nick: Fascinating. When you find the QEX article please report
back.
73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:
"Nick Kennedy" wrote in message
news:BWcdf.2375$ih5.1677@dukeread11...
"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