time sync by moonbounce
Apparently, they used moonbounce between DSN stations to synchronize to
5 microseconds in 1968. It was easier and cheaper than flying cesium
clocks around. (And the Rb standards weren't good enough).
https://ntrs.nasa.gov/search.jsp?R=19770007245
History of DSN - mostly about politics, history, transmitters and
receivers, but a whole section on timekeeping, phase measurements, etc.
starting around page 133 (The DSN Inherent accuracy project), and the
discovery during Mariner that UTC and UTI were different enough to cause
nav errors.
This is a must read. Could not put it down, JPL, NASA, Eisenhowe,r did learn a lot at the same time fascinating
Bert Kehren
In a message dated 5/22/2020 10:36:53 PM Eastern Standard Time, jimlux@earthlink.net writes:
Apparently, they used moonbounce between DSN stations to synchronize to 5 microseconds in 1968. It was easier and cheaper than flying cesium clocks around. (And the Rb standards weren't good enough).
https://ntrs.nasa.gov/search.jsp?R=19770007245
History of DSN - mostly about politics, history, transmitters and receivers, but a whole section on timekeeping, phase measurements, etc. starting around page 133 (The DSN Inherent accuracy project), and the discovery during Mariner that UTC and UTI were different enough to cause nav errors.
_______________________________________________time-nuts mailing list -- time-nuts@lists.febo.comTo unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.comand follow the instructions there.
Sufficiently interesting that I bought a paper copy through Abebooks. Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices from
reasonable to ridiculous, as is usual for bookstores.
Jeremy
On Sat, May 23, 2020 at 3:47 AM ew via time-nuts time-nuts@lists.febo.com
wrote:
This is a must read. Could not put it down, JPL, NASA, Eisenhowe,r did
learn a lot at the same time fascinating
Bert Kehren
In a message dated 5/22/2020 10:36:53 PM Eastern Standard Time,
jimlux@earthlink.net writes:
Apparently, they used moonbounce between DSN stations to synchronize to 5
microseconds in 1968. It was easier and cheaper than flying cesium clocks
around. (And the Rb standards weren't good enough).
https://ntrs.nasa.gov/search.jsp?R=19770007245
History of DSN - mostly about politics, history, transmitters and
receivers, but a whole section on timekeeping, phase measurements, etc.
starting around page 133 (The DSN Inherent accuracy project), and the
discovery during Mariner that UTC and UTI were different enough to cause
nav errors.
_______________________________________________time-nuts mailing list --
time-nuts@lists.febo.comTo unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.comand follow
the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
--
Jeremy Nichols
Sent from my iPad 6.
You talked me in to it.
Wes N7WS
On 5/23/2020 8:19 AM, Jeremy Nichols wrote:
Sufficiently interesting that I bought a paper copy through Abebooks. Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices from
reasonable to ridiculous, as is usual for bookstores.
Jeremy
On Sat, May 23, 2020 at 3:47 AM ew via time-nuts time-nuts@lists.febo.com
wrote:
This is a must read. Could not put it down, JPL, NASA, Eisenhowe,r did
learn a lot at the same time fascinating
Bert Kehren
In a message dated 5/22/2020 10:36:53 PM Eastern Standard Time,
jimlux@earthlink.net writes:
Apparently, they used moonbounce between DSN stations to synchronize to 5
microseconds in 1968. It was easier and cheaper than flying cesium clocks
around. (And the Rb standards weren't good enough).
https://ntrs.nasa.gov/search.jsp?R=19770007245
History of DSN - mostly about politics, history, transmitters and
receivers, but a whole section on timekeeping, phase measurements, etc.
starting around page 133 (The DSN Inherent accuracy project), and the
discovery during Mariner that UTC and UTI were different enough to cause
nav errors.
_______________________________________________time-nuts mailing list --
time-nuts@lists.febo.comTo unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.comand follow
the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
Mike - M0MLM
On 23/05/2020 17:12, Wes wrote:
You talked me in to it.
Wes N7WS
On 5/23/2020 8:19 AM, Jeremy Nichols wrote:
Sufficiently interesting that I bought a paper copy through Abebooks.
Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices
from
reasonable to ridiculous, as is usual for bookstores.
Jeremy
I think this is available here:
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020033033.pdf and
here:
https://books.google.pl/books?id=vn5TAAAAMAAJ&printsec=frontcover&hl=pl&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false
Best regards,
Adam Kumiszcza
On Sat, May 23, 2020 at 5:20 PM Jeremy Nichols jn6wfo@gmail.com wrote:
Sufficiently interesting that I bought a paper copy through Abebooks. Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices from
reasonable to ridiculous, as is usual for bookstores.
Jeremy
On Sat, May 23, 2020 at 3:47 AM ew via time-nuts <time-nuts@lists.febo.com
wrote:
This is a must read. Could not put it down, JPL, NASA, Eisenhowe,r did
learn a lot at the same time fascinating
Bert Kehren
In a message dated 5/22/2020 10:36:53 PM Eastern Standard Time,
jimlux@earthlink.net writes:
Apparently, they used moonbounce between DSN stations to synchronize to 5
microseconds in 1968. It was easier and cheaper than flying cesium clocks
around. (And the Rb standards weren't good enough).
https://ntrs.nasa.gov/search.jsp?R=19770007245
History of DSN - mostly about politics, history, transmitters and
receivers, but a whole section on timekeeping, phase measurements, etc.
starting around page 133 (The DSN Inherent accuracy project), and the
discovery during Mariner that UTC and UTI were different enough to cause
nav errors.
_______________________________________________time-nuts mailing list --
time-nuts@lists.febo.comTo unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.comand
follow
the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
--
Jeremy Nichols
Sent from my iPad 6.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
On 5/23/20 8:19 AM, Jeremy Nichols wrote:
Sufficiently interesting that I bought a paper copy through Abebooks. Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices from
reasonable to ridiculous, as is usual for bookstores.
Different author (The report I pointed to is by William Corliss), but
perhaps the same source material, (at least up to 1975)
it's available as a downloadable pdf, theoretically (although the link
is to the cover page only) - I'll talk to the site owner and get that fixed.
https://descanso.jpl.nasa.gov/history/dsnHistory.html
(there's a version here:
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020033033.pdf)
The second link on the dsnhistory page, to a list of references, is
something you might find interesting.
There's a set of books published by JPL at
https://descanso.jpl.nasa.gov/
Various series.. Some are not particularly time-nutty, but some are -
I'd look for things on radiometric tracking and nav.
Here's a whole series on it:
https://descanso.jpl.nasa.gov/evolution/evolution.html - not much
technical detail in the paper, more a history of what was done when, but
the papers in the references might be useful.
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the DSN,
then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it at
JPL - correcting the pdf/microfilm is probably beyond scope)
Mike - M0MLM
On 23/05/2020 17:12, Wes wrote:
You talked me in to it.
Wes N7WS
On 5/23/2020 8:19 AM, Jeremy Nichols wrote:
Sufficiently interesting that I bought a paper copy through Abebooks.
Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices
from
reasonable to ridiculous, as is usual for bookstores.
Jeremy
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
On 5/23/20 8:19 AM, Jeremy Nichols wrote:
Sufficiently interesting that I bought a paper copy through Abebooks. Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices from
reasonable to ridiculous, as is usual for bookstores.
Jeremy
A good read (there's a morning for you)... Not much technical detail in
the book (it's a history, not a textbook), but there are good
references. An interesting comment in the early part about why there's
not a good set of documents to refer to.
That’s it! And Author Mudgway turns out to be from Sonoma, a town in my
county just a few miles east of me. I wonder if I can get him to sign my
copy when it comes out?
On Sat, May 23, 2020 at 3:52 PM Adam Kumiszcza akumiszcza@gmail.com wrote:
I think this is available here:
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020033033.pdf and
here:
Best regards,
Adam Kumiszcza
On Sat, May 23, 2020 at 5:20 PM Jeremy Nichols jn6wfo@gmail.com wrote:
Sufficiently interesting that I bought a paper copy through Abebooks.
Looks
like a somewhat later version, author given as Douglas Mudgway, title
“ Uplink-Downlink:
A History of the Deep Space Network 1957-1997.” “Oversized,” 674
pages. Abebooks
lists a couple dozen copies in both hardback and paperback at prices from
reasonable to ridiculous, as is usual for bookstores.
Jeremy
On Sat, May 23, 2020 at 3:47 AM ew via time-nuts <
wrote:
This is a must read. Could not put it down, JPL, NASA, Eisenhowe,r did
learn a lot at the same time fascinating
Bert Kehren
In a message dated 5/22/2020 10:36:53 PM Eastern Standard Time,
jimlux@earthlink.net writes:
Apparently, they used moonbounce between DSN stations to synchronize
to 5
microseconds in 1968. It was easier and cheaper than flying cesium
clocks
around. (And the Rb standards weren't good enough).
https://ntrs.nasa.gov/search.jsp?R=19770007245
History of DSN - mostly about politics, history, transmitters and
receivers, but a whole section on timekeeping, phase measurements, etc.
starting around page 133 (The DSN Inherent accuracy project), and the
discovery during Mariner that UTC and UTI were different enough to
cause
nav errors.
_______________________________________________time-nuts mailing list
--
time-nuts@lists.febo.comTo unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.comand
follow
the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
--
Jeremy Nichols
Sent from my iPad 6.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
--
Jeremy Nichols
Sent from my iPad 6.
Hi Jim,
This explains a lot of things. As an old time user of the Moon Bounce
time synchronization in the Madrid Space Complex, I can say that the
system was never popular among the users, it was cumbersome to use and
there were already other systems with better accuracy and availability,
such as VLBI and Loran-C. We used Loran-C as our daily reference
because we had a station at a distance of 650 Km and the signal was very
good, even with an old receiver who needed manual estimation of the
delay the results were very good. Maybe the aliens who designed the
system were not very aware of the humans idiosyncrasies
I think that the idea was good, but the implementation was not so good.
I can summarize the "peculiarities" as I remember them:
-
The transmissions had to be scheduled for a period of common moon
view. The receiving station was manned 7/24 but the transmitting station
(DSS13, if I remember it correctly) had to be manned specially for the
event by a crew probably from Barstow, some 40 miles away. -
Normally there were not provisions for voice communications between
the two end points, so if we did not got correlations we didn't know if
the transmitting station was working ok or even if it was not manned due
to some problem. -
There were not monitoring aids in the receiver, so if we did not have
correlations, we has to climb to the roof, verify the pointing of the
antenna (there were a rifle scope for that), and if it was, tried to
contact DSS13 by phone and pray. -
As you can figure it out, the antenna was not remotely controlled. One
had to climb to the roof, set the moon declination for that day using a
handwheel, slew the hour angle with a switch and select the hour angle
rate with another switch. The moon position and rate was obtained from a
nautical almanac and when the sky was clear we used the above mentioned
rifle scope.
The receiver was quite dumb, all intelligence was on the transmitter
site. The TX equipment generated a PN code that lasted about 1s, and a
full observation cycle lasted about a minute, I don't remember the exact
figures. The code was sent advanced to take care of the round trip light
time but an additional time bias of 30 us was also introduced which was
the basis of the measurement. The bias was decreased 1us/s, so
theoretically it was received just on time in the second 30.
The receiver generated the same PN using the station timing reference
(from a HP 5065A Rb) and it was correlated with the received code. The
output of the correlator was integrated and sent to a strip chart
recorder. The graph consisted in one trace with a quite noisy ramp and
the other trace with 1PPS from the station reference. Now the weird
thing: after finishing an observation, we put the graph in a desk and
using a drafting rule we draw a straight line that tried to be the "best
fit" to the noisy ramp. Were the line crossed the zero we read the PPS
mark there and counting back to the start of the minute we got the PPS
offset with respect to the transmitting station. Of course we averaged
the values obtained from several minutes, after discarding the noisiest
ones.
Since we didn't had any faith in the system we didn't tried to suggest
improvements or improve it ourselves. A good one could be to use a
computer program to perform the best fit analytically, but this would
mean to type the hundreds of points manually from the graph and we never
tried this. There were not a digital version of the output, we also
could use a digital voltmeter for acquiring it. We suggested or
implemented a lot of improvements to other operational things, but this
contraption was felt as a dead horse from the beginning and its
operational life was short. Later it was replaced with a GPS based one:
2 full height racks filled with equipment and an antenna made from a 10
or 20 gallon hermetic paint drum for housing the front end electronics,
topped with a fiberglass radome about 1 1/2 ' in diameter. It was
painted white, but the cylinder origin was discovered during a
maintenance. It was a beautiful prototype that worked very well during
its shot life.
I don't keep pictures of this equipment, but I have one with the same
antenna used for other purposes.
Sorry for the bandwidth, but the thread brought me old memories.
Best regards,
Ignacio
El 23/05/2020 a las 19:17, jimlux escribió:
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the
DSN, then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it
at JPL - correcting the pdf/microfilm is probably beyond scope)
--
El software de antivirus Avast ha analizado este correo electrónico en busca de virus.
https://www.avast.com/antivirus
I bought a used copy of Uplink-Downlink on Ebay.
Unfortunately the quality is downright bad. Printed on what looks like
bright white copy paper with a laser printer.
All the images and illustrations are rasterized, the text is low
resolution. The photo on the cover shows compression artifacts.
The last page reveals the culprit: "Printed in Great Britain by Amazon.co.uk
"
A quick search shows similar experiences with other print on demand books
from Amazon.
Unfortunately there's no way to tell if a book was printed on demand, most
listings just show the cover image instead of a photo of the actual book.
I will try to return it, if I don't have to cover shipping costs.
Buyer beware...
Wannes
On Mon, May 25, 2020 at 4:46 PM EB4APL eb4apl@gmail.com wrote:
Hi Jim,
This explains a lot of things. As an old time user of the Moon Bounce
time synchronization in the Madrid Space Complex, I can say that the
system was never popular among the users, it was cumbersome to use and
there were already other systems with better accuracy and availability,
such as VLBI and Loran-C. We used Loran-C as our daily reference
because we had a station at a distance of 650 Km and the signal was very
good, even with an old receiver who needed manual estimation of the
delay the results were very good. Maybe the aliens who designed the
system were not very aware of the humans idiosyncrasies
I think that the idea was good, but the implementation was not so good.
I can summarize the "peculiarities" as I remember them:
-
The transmissions had to be scheduled for a period of common moon
view. The receiving station was manned 7/24 but the transmitting station
(DSS13, if I remember it correctly) had to be manned specially for the
event by a crew probably from Barstow, some 40 miles away. -
Normally there were not provisions for voice communications between
the two end points, so if we did not got correlations we didn't know if
the transmitting station was working ok or even if it was not manned due
to some problem. -
There were not monitoring aids in the receiver, so if we did not have
correlations, we has to climb to the roof, verify the pointing of the
antenna (there were a rifle scope for that), and if it was, tried to
contact DSS13 by phone and pray. -
As you can figure it out, the antenna was not remotely controlled. One
had to climb to the roof, set the moon declination for that day using a
handwheel, slew the hour angle with a switch and select the hour angle
rate with another switch. The moon position and rate was obtained from a
nautical almanac and when the sky was clear we used the above mentioned
rifle scope.
The receiver was quite dumb, all intelligence was on the transmitter
site. The TX equipment generated a PN code that lasted about 1s, and a
full observation cycle lasted about a minute, I don't remember the exact
figures. The code was sent advanced to take care of the round trip light
time but an additional time bias of 30 us was also introduced which was
the basis of the measurement. The bias was decreased 1us/s, so
theoretically it was received just on time in the second 30.
The receiver generated the same PN using the station timing reference
(from a HP 5065A Rb) and it was correlated with the received code. The
output of the correlator was integrated and sent to a strip chart
recorder. The graph consisted in one trace with a quite noisy ramp and
the other trace with 1PPS from the station reference. Now the weird
thing: after finishing an observation, we put the graph in a desk and
using a drafting rule we draw a straight line that tried to be the "best
fit" to the noisy ramp. Were the line crossed the zero we read the PPS
mark there and counting back to the start of the minute we got the PPS
offset with respect to the transmitting station. Of course we averaged
the values obtained from several minutes, after discarding the noisiest
ones.
Since we didn't had any faith in the system we didn't tried to suggest
improvements or improve it ourselves. A good one could be to use a
computer program to perform the best fit analytically, but this would
mean to type the hundreds of points manually from the graph and we never
tried this. There were not a digital version of the output, we also
could use a digital voltmeter for acquiring it. We suggested or
implemented a lot of improvements to other operational things, but this
contraption was felt as a dead horse from the beginning and its
operational life was short. Later it was replaced with a GPS based one:
2 full height racks filled with equipment and an antenna made from a 10
or 20 gallon hermetic paint drum for housing the front end electronics,
topped with a fiberglass radome about 1 1/2 ' in diameter. It was
painted white, but the cylinder origin was discovered during a
maintenance. It was a beautiful prototype that worked very well during
its shot life.
I don't keep pictures of this equipment, but I have one with the same
antenna used for other purposes.
Sorry for the bandwidth, but the thread brought me old memories.
Best regards,
Ignacio
El 23/05/2020 a las 19:17, jimlux escribió:
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the
DSN, then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it
at JPL - correcting the pdf/microfilm is probably beyond scope)
--
El software de antivirus Avast ha analizado este correo electrónico en
busca de virus.
https://www.avast.com/antivirus
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
My copy is an original, bought from one of the Abebooks sellers. It’s a
huge book and the type is on the small side; I’m still working my way
through the Introduction. Looks like a lot of good information.
Jeremy
On Mon, Jun 8, 2020 at 5:23 AM Wannes Sels wannes.sels@gmail.com wrote:
I bought a used copy of Uplink-Downlink on Ebay.
Unfortunately the quality is downright bad. Printed on what looks like
bright white copy paper with a laser printer.
All the images and illustrations are rasterized, the text is low
resolution. The photo on the cover shows compression artifacts.
The last page reveals the culprit: "Printed in Great Britain by
Amazon.co.uk
"
A quick search shows similar experiences with other print on demand books
from Amazon.
Unfortunately there's no way to tell if a book was printed on demand, most
listings just show the cover image instead of a photo of the actual book.
I will try to return it, if I don't have to cover shipping costs.
Buyer beware...
Wannes
On Mon, May 25, 2020 at 4:46 PM EB4APL eb4apl@gmail.com wrote:
Hi Jim,
This explains a lot of things. As an old time user of the Moon Bounce
time synchronization in the Madrid Space Complex, I can say that the
system was never popular among the users, it was cumbersome to use and
there were already other systems with better accuracy and availability,
such as VLBI and Loran-C. We used Loran-C as our daily reference
because we had a station at a distance of 650 Km and the signal was very
good, even with an old receiver who needed manual estimation of the
delay the results were very good. Maybe the aliens who designed the
system were not very aware of the humans idiosyncrasies
I think that the idea was good, but the implementation was not so good.
I can summarize the "peculiarities" as I remember them:
-
The transmissions had to be scheduled for a period of common moon
view. The receiving station was manned 7/24 but the transmitting station
(DSS13, if I remember it correctly) had to be manned specially for the
event by a crew probably from Barstow, some 40 miles away. -
Normally there were not provisions for voice communications between
the two end points, so if we did not got correlations we didn't know if
the transmitting station was working ok or even if it was not manned due
to some problem. -
There were not monitoring aids in the receiver, so if we did not have
correlations, we has to climb to the roof, verify the pointing of the
antenna (there were a rifle scope for that), and if it was, tried to
contact DSS13 by phone and pray. -
As you can figure it out, the antenna was not remotely controlled. One
had to climb to the roof, set the moon declination for that day using a
handwheel, slew the hour angle with a switch and select the hour angle
rate with another switch. The moon position and rate was obtained from a
nautical almanac and when the sky was clear we used the above mentioned
rifle scope.
The receiver was quite dumb, all intelligence was on the transmitter
site. The TX equipment generated a PN code that lasted about 1s, and a
full observation cycle lasted about a minute, I don't remember the exact
figures. The code was sent advanced to take care of the round trip light
time but an additional time bias of 30 us was also introduced which was
the basis of the measurement. The bias was decreased 1us/s, so
theoretically it was received just on time in the second 30.
The receiver generated the same PN using the station timing reference
(from a HP 5065A Rb) and it was correlated with the received code. The
output of the correlator was integrated and sent to a strip chart
recorder. The graph consisted in one trace with a quite noisy ramp and
the other trace with 1PPS from the station reference. Now the weird
thing: after finishing an observation, we put the graph in a desk and
using a drafting rule we draw a straight line that tried to be the "best
fit" to the noisy ramp. Were the line crossed the zero we read the PPS
mark there and counting back to the start of the minute we got the PPS
offset with respect to the transmitting station. Of course we averaged
the values obtained from several minutes, after discarding the noisiest
ones.
Since we didn't had any faith in the system we didn't tried to suggest
improvements or improve it ourselves. A good one could be to use a
computer program to perform the best fit analytically, but this would
mean to type the hundreds of points manually from the graph and we never
tried this. There were not a digital version of the output, we also
could use a digital voltmeter for acquiring it. We suggested or
implemented a lot of improvements to other operational things, but this
contraption was felt as a dead horse from the beginning and its
operational life was short. Later it was replaced with a GPS based one:
2 full height racks filled with equipment and an antenna made from a 10
or 20 gallon hermetic paint drum for housing the front end electronics,
topped with a fiberglass radome about 1 1/2 ' in diameter. It was
painted white, but the cylinder origin was discovered during a
maintenance. It was a beautiful prototype that worked very well during
its shot life.
I don't keep pictures of this equipment, but I have one with the same
antenna used for other purposes.
Sorry for the bandwidth, but the thread brought me old memories.
Best regards,
Ignacio
El 23/05/2020 a las 19:17, jimlux escribió:
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the
DSN, then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it
at JPL - correcting the pdf/microfilm is probably beyond scope)
--
El software de antivirus Avast ha analizado este correo electrónico en
busca de virus.
https://www.avast.com/antivirus
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
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and follow the instructions there.
--
Jeremy Nichols
Sent from my iPad 6.
Many thanks Wannes for the warning
Jean-Louis
Le 06/06/2020 à 00:43, Wannes Sels a écrit :
I bought a used copy of Uplink-Downlink on Ebay.
Unfortunately the quality is downright bad. Printed on what looks like
bright white copy paper with a laser printer.
All the images and illustrations are rasterized, the text is low
resolution. The photo on the cover shows compression artifacts.
The last page reveals the culprit: "Printed in Great Britain by Amazon.co.uk
"
A quick search shows similar experiences with other print on demand books
from Amazon.
Unfortunately there's no way to tell if a book was printed on demand, most
listings just show the cover image instead of a photo of the actual book.
I will try to return it, if I don't have to cover shipping costs.
Buyer beware...
Wannes
On Mon, May 25, 2020 at 4:46 PM EB4APL eb4apl@gmail.com wrote:
Hi Jim,
This explains a lot of things. As an old time user of the Moon Bounce
time synchronization in the Madrid Space Complex, I can say that the
system was never popular among the users, it was cumbersome to use and
there were already other systems with better accuracy and availability,
such as VLBI and Loran-C. We used Loran-C as our daily reference
because we had a station at a distance of 650 Km and the signal was very
good, even with an old receiver who needed manual estimation of the
delay the results were very good. Maybe the aliens who designed the
system were not very aware of the humans idiosyncrasies
I think that the idea was good, but the implementation was not so good.
I can summarize the "peculiarities" as I remember them:
-
The transmissions had to be scheduled for a period of common moon
view. The receiving station was manned 7/24 but the transmitting station
(DSS13, if I remember it correctly) had to be manned specially for the
event by a crew probably from Barstow, some 40 miles away. -
Normally there were not provisions for voice communications between
the two end points, so if we did not got correlations we didn't know if
the transmitting station was working ok or even if it was not manned due
to some problem. -
There were not monitoring aids in the receiver, so if we did not have
correlations, we has to climb to the roof, verify the pointing of the
antenna (there were a rifle scope for that), and if it was, tried to
contact DSS13 by phone and pray. -
As you can figure it out, the antenna was not remotely controlled. One
had to climb to the roof, set the moon declination for that day using a
handwheel, slew the hour angle with a switch and select the hour angle
rate with another switch. The moon position and rate was obtained from a
nautical almanac and when the sky was clear we used the above mentioned
rifle scope.
The receiver was quite dumb, all intelligence was on the transmitter
site. The TX equipment generated a PN code that lasted about 1s, and a
full observation cycle lasted about a minute, I don't remember the exact
figures. The code was sent advanced to take care of the round trip light
time but an additional time bias of 30 us was also introduced which was
the basis of the measurement. The bias was decreased 1us/s, so
theoretically it was received just on time in the second 30.
The receiver generated the same PN using the station timing reference
(from a HP 5065A Rb) and it was correlated with the received code. The
output of the correlator was integrated and sent to a strip chart
recorder. The graph consisted in one trace with a quite noisy ramp and
the other trace with 1PPS from the station reference. Now the weird
thing: after finishing an observation, we put the graph in a desk and
using a drafting rule we draw a straight line that tried to be the "best
fit" to the noisy ramp. Were the line crossed the zero we read the PPS
mark there and counting back to the start of the minute we got the PPS
offset with respect to the transmitting station. Of course we averaged
the values obtained from several minutes, after discarding the noisiest
ones.
Since we didn't had any faith in the system we didn't tried to suggest
improvements or improve it ourselves. A good one could be to use a
computer program to perform the best fit analytically, but this would
mean to type the hundreds of points manually from the graph and we never
tried this. There were not a digital version of the output, we also
could use a digital voltmeter for acquiring it. We suggested or
implemented a lot of improvements to other operational things, but this
contraption was felt as a dead horse from the beginning and its
operational life was short. Later it was replaced with a GPS based one:
2 full height racks filled with equipment and an antenna made from a 10
or 20 gallon hermetic paint drum for housing the front end electronics,
topped with a fiberglass radome about 1 1/2 ' in diameter. It was
painted white, but the cylinder origin was discovered during a
maintenance. It was a beautiful prototype that worked very well during
its shot life.
I don't keep pictures of this equipment, but I have one with the same
antenna used for other purposes.
Sorry for the bandwidth, but the thread brought me old memories.
Best regards,
Ignacio
El 23/05/2020 a las 19:17, jimlux escribió:
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the
DSN, then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it
at JPL - correcting the pdf/microfilm is probably beyond scope)
--
El software de antivirus Avast ha analizado este correo electrónico en
busca de virus.
https://www.avast.com/antivirus
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
I also bought my copy of "Uplink-Downlink" through Amazon but had better
luck. The cover photo is in color, not quite as sharp as I would have
preferred
but has no apparent compression artifacts.
The text inside is of good quality- nop complaints in this department.
However, the photos inside are of poor quality. They are screen-printed,
with
the screen elements as big as basketballs, and in general any text within
the
photo-proper is completely unreadable. But the captions are just fine.
I've been unable to find any publisher's info, just a note on the back
dustcover
stating "Made in the USA; Coppell, TX; 30 May 2020". It arrived at my home
in Kerrville, TX three days later, so I presume that the copy was custom
printed
just for me.
Dana
On Mon, Jun 8, 2020 at 7:23 AM Wannes Sels wannes.sels@gmail.com wrote:
I bought a used copy of Uplink-Downlink on Ebay.
Unfortunately the quality is downright bad. Printed on what looks like
bright white copy paper with a laser printer.
All the images and illustrations are rasterized, the text is low
resolution. The photo on the cover shows compression artifacts.
The last page reveals the culprit: "Printed in Great Britain by
Amazon.co.uk
"
A quick search shows similar experiences with other print on demand books
from Amazon.
Unfortunately there's no way to tell if a book was printed on demand, most
listings just show the cover image instead of a photo of the actual book.
I will try to return it, if I don't have to cover shipping costs.
Buyer beware...
Wannes
On Mon, May 25, 2020 at 4:46 PM EB4APL eb4apl@gmail.com wrote:
Hi Jim,
This explains a lot of things. As an old time user of the Moon Bounce
time synchronization in the Madrid Space Complex, I can say that the
system was never popular among the users, it was cumbersome to use and
there were already other systems with better accuracy and availability,
such as VLBI and Loran-C. We used Loran-C as our daily reference
because we had a station at a distance of 650 Km and the signal was very
good, even with an old receiver who needed manual estimation of the
delay the results were very good. Maybe the aliens who designed the
system were not very aware of the humans idiosyncrasies
I think that the idea was good, but the implementation was not so good.
I can summarize the "peculiarities" as I remember them:
-
The transmissions had to be scheduled for a period of common moon
view. The receiving station was manned 7/24 but the transmitting station
(DSS13, if I remember it correctly) had to be manned specially for the
event by a crew probably from Barstow, some 40 miles away. -
Normally there were not provisions for voice communications between
the two end points, so if we did not got correlations we didn't know if
the transmitting station was working ok or even if it was not manned due
to some problem. -
There were not monitoring aids in the receiver, so if we did not have
correlations, we has to climb to the roof, verify the pointing of the
antenna (there were a rifle scope for that), and if it was, tried to
contact DSS13 by phone and pray. -
As you can figure it out, the antenna was not remotely controlled. One
had to climb to the roof, set the moon declination for that day using a
handwheel, slew the hour angle with a switch and select the hour angle
rate with another switch. The moon position and rate was obtained from a
nautical almanac and when the sky was clear we used the above mentioned
rifle scope.
The receiver was quite dumb, all intelligence was on the transmitter
site. The TX equipment generated a PN code that lasted about 1s, and a
full observation cycle lasted about a minute, I don't remember the exact
figures. The code was sent advanced to take care of the round trip light
time but an additional time bias of 30 us was also introduced which was
the basis of the measurement. The bias was decreased 1us/s, so
theoretically it was received just on time in the second 30.
The receiver generated the same PN using the station timing reference
(from a HP 5065A Rb) and it was correlated with the received code. The
output of the correlator was integrated and sent to a strip chart
recorder. The graph consisted in one trace with a quite noisy ramp and
the other trace with 1PPS from the station reference. Now the weird
thing: after finishing an observation, we put the graph in a desk and
using a drafting rule we draw a straight line that tried to be the "best
fit" to the noisy ramp. Were the line crossed the zero we read the PPS
mark there and counting back to the start of the minute we got the PPS
offset with respect to the transmitting station. Of course we averaged
the values obtained from several minutes, after discarding the noisiest
ones.
Since we didn't had any faith in the system we didn't tried to suggest
improvements or improve it ourselves. A good one could be to use a
computer program to perform the best fit analytically, but this would
mean to type the hundreds of points manually from the graph and we never
tried this. There were not a digital version of the output, we also
could use a digital voltmeter for acquiring it. We suggested or
implemented a lot of improvements to other operational things, but this
contraption was felt as a dead horse from the beginning and its
operational life was short. Later it was replaced with a GPS based one:
2 full height racks filled with equipment and an antenna made from a 10
or 20 gallon hermetic paint drum for housing the front end electronics,
topped with a fiberglass radome about 1 1/2 ' in diameter. It was
painted white, but the cylinder origin was discovered during a
maintenance. It was a beautiful prototype that worked very well during
its shot life.
I don't keep pictures of this equipment, but I have one with the same
antenna used for other purposes.
Sorry for the bandwidth, but the thread brought me old memories.
Best regards,
Ignacio
El 23/05/2020 a las 19:17, jimlux escribió:
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the
DSN, then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it
at JPL - correcting the pdf/microfilm is probably beyond scope)
--
El software de antivirus Avast ha analizado este correo electrónico en
busca de virus.
https://www.avast.com/antivirus
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
On 6/5/20 3:43 PM, Wannes Sels wrote:
I bought a used copy of Uplink-Downlink on Ebay.
Unfortunately the quality is downright bad. Printed on what looks like
bright white copy paper with a laser printer.
All the images and illustrations are rasterized, the text is low
resolution. The photo on the cover shows compression artifacts.
The pdf on the NASA site is of similar quality, and probably what the
"print to order" version is printed from.
I don't know where one would go about getting a copy of the GPO printed
version - perhaps a used book dealer.
Conceivably, someone could get a good copy from a library that happens
to have it and spend the time to scan it.
The last page reveals the culprit: "Printed in Great Britain by Amazon.co.uk
"
A quick search shows similar experiences with other print on demand books
from Amazon.
Unfortunately there's no way to tell if a book was printed on demand, most
listings just show the cover image instead of a photo of the actual book.
I will try to return it, if I don't have to cover shipping costs.
Buyer beware...
Wannes
On Mon, May 25, 2020 at 4:46 PM EB4APL eb4apl@gmail.com wrote:
Hi Jim,
This explains a lot of things. As an old time user of the Moon Bounce
time synchronization in the Madrid Space Complex, I can say that the
system was never popular among the users, it was cumbersome to use and
there were already other systems with better accuracy and availability,
such as VLBI and Loran-C. We used Loran-C as our daily reference
because we had a station at a distance of 650 Km and the signal was very
good, even with an old receiver who needed manual estimation of the
delay the results were very good. Maybe the aliens who designed the
system were not very aware of the humans idiosyncrasies
I think that the idea was good, but the implementation was not so good.
I can summarize the "peculiarities" as I remember them:
-
The transmissions had to be scheduled for a period of common moon
view. The receiving station was manned 7/24 but the transmitting station
(DSS13, if I remember it correctly) had to be manned specially for the
event by a crew probably from Barstow, some 40 miles away. -
Normally there were not provisions for voice communications between
the two end points, so if we did not got correlations we didn't know if
the transmitting station was working ok or even if it was not manned due
to some problem. -
There were not monitoring aids in the receiver, so if we did not have
correlations, we has to climb to the roof, verify the pointing of the
antenna (there were a rifle scope for that), and if it was, tried to
contact DSS13 by phone and pray. -
As you can figure it out, the antenna was not remotely controlled. One
had to climb to the roof, set the moon declination for that day using a
handwheel, slew the hour angle with a switch and select the hour angle
rate with another switch. The moon position and rate was obtained from a
nautical almanac and when the sky was clear we used the above mentioned
rifle scope.
The receiver was quite dumb, all intelligence was on the transmitter
site. The TX equipment generated a PN code that lasted about 1s, and a
full observation cycle lasted about a minute, I don't remember the exact
figures. The code was sent advanced to take care of the round trip light
time but an additional time bias of 30 us was also introduced which was
the basis of the measurement. The bias was decreased 1us/s, so
theoretically it was received just on time in the second 30.
The receiver generated the same PN using the station timing reference
(from a HP 5065A Rb) and it was correlated with the received code. The
output of the correlator was integrated and sent to a strip chart
recorder. The graph consisted in one trace with a quite noisy ramp and
the other trace with 1PPS from the station reference. Now the weird
thing: after finishing an observation, we put the graph in a desk and
using a drafting rule we draw a straight line that tried to be the "best
fit" to the noisy ramp. Were the line crossed the zero we read the PPS
mark there and counting back to the start of the minute we got the PPS
offset with respect to the transmitting station. Of course we averaged
the values obtained from several minutes, after discarding the noisiest
ones.
Since we didn't had any faith in the system we didn't tried to suggest
improvements or improve it ourselves. A good one could be to use a
computer program to perform the best fit analytically, but this would
mean to type the hundreds of points manually from the graph and we never
tried this. There were not a digital version of the output, we also
could use a digital voltmeter for acquiring it. We suggested or
implemented a lot of improvements to other operational things, but this
contraption was felt as a dead horse from the beginning and its
operational life was short. Later it was replaced with a GPS based one:
2 full height racks filled with equipment and an antenna made from a 10
or 20 gallon hermetic paint drum for housing the front end electronics,
topped with a fiberglass radome about 1 1/2 ' in diameter. It was
painted white, but the cylinder origin was discovered during a
maintenance. It was a beautiful prototype that worked very well during
its shot life.
I don't keep pictures of this equipment, but I have one with the same
antenna used for other purposes.
Sorry for the bandwidth, but the thread brought me old memories.
Best regards,
Ignacio
El 23/05/2020 a las 19:17, jimlux escribió:
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the
DSN, then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it
at JPL - correcting the pdf/microfilm is probably beyond scope)
--
El software de antivirus Avast ha analizado este correo electrónico en
busca de virus.
https://www.avast.com/antivirus
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
A quick search shows similar experiences with other print on demand books
from Amazon.
Off topic:
A closely related division within the company I worked for made ultrahigh speed printers
Paper reels were maybe 2 m in diameter
Connections between the computers and printer were fiber (copper was too slow).
Printer, computer, and paper fill a _very_ large room (250 sq m?).
I don’t know if they cost more than USD 1M.
On a factory tour, I learned that virtually all amazon books (at least in US), other than,
say, the latest #1 best seller in hard cover, are printed on demand.
As is virtually all customized mail (e.g. financial statements, etc.)
(Obviously) a poor scan will result in a poor print on demand book.
But the print on demand process itself is amazing — ‘you wouldn’t even know’.
Best,
Scott W7SLS
My 2001 copy of Uplink-Downlink was printed by GPO and is 674 pages of
10-point type. I would not want to scan it! Anyway, it was only $25 from an
Abebooks seller including tax and shipping and is in near-new condition
including a plastic-wrapped dust jacket.
Jeremy
On Mon, Jun 8, 2020 at 1:01 PM jimlux jimlux@earthlink.net wrote:
On 6/5/20 3:43 PM, Wannes Sels wrote:
I bought a used copy of Uplink-Downlink on Ebay.
Unfortunately the quality is downright bad. Printed on what looks like
bright white copy paper with a laser printer.
All the images and illustrations are rasterized, the text is low
resolution. The photo on the cover shows compression artifacts.
The pdf on the NASA site is of similar quality, and probably what the
"print to order" version is printed from.
I don't know where one would go about getting a copy of the GPO printed
version - perhaps a used book dealer.
Conceivably, someone could get a good copy from a library that happens
to have it and spend the time to scan it.
The last page reveals the culprit: "Printed in Great Britain by
Amazon.co.uk
"
A quick search shows similar experiences with other print on demand books
from Amazon.
Unfortunately there's no way to tell if a book was printed on demand,
most
listings just show the cover image instead of a photo of the actual book.
I will try to return it, if I don't have to cover shipping costs.
Buyer beware...
Wannes
On Mon, May 25, 2020 at 4:46 PM EB4APL eb4apl@gmail.com wrote:
Hi Jim,
This explains a lot of things. As an old time user of the Moon Bounce
time synchronization in the Madrid Space Complex, I can say that the
system was never popular among the users, it was cumbersome to use and
there were already other systems with better accuracy and availability,
such as VLBI and Loran-C. We used Loran-C as our daily reference
because we had a station at a distance of 650 Km and the signal was very
good, even with an old receiver who needed manual estimation of the
delay the results were very good. Maybe the aliens who designed the
system were not very aware of the humans idiosyncrasies
I think that the idea was good, but the implementation was not so good.
I can summarize the "peculiarities" as I remember them:
-
The transmissions had to be scheduled for a period of common moon
view. The receiving station was manned 7/24 but the transmitting station
(DSS13, if I remember it correctly) had to be manned specially for the
event by a crew probably from Barstow, some 40 miles away. -
Normally there were not provisions for voice communications between
the two end points, so if we did not got correlations we didn't know if
the transmitting station was working ok or even if it was not manned due
to some problem. -
There were not monitoring aids in the receiver, so if we did not have
correlations, we has to climb to the roof, verify the pointing of the
antenna (there were a rifle scope for that), and if it was, tried to
contact DSS13 by phone and pray. -
As you can figure it out, the antenna was not remotely controlled. One
had to climb to the roof, set the moon declination for that day using a
handwheel, slew the hour angle with a switch and select the hour angle
rate with another switch. The moon position and rate was obtained from a
nautical almanac and when the sky was clear we used the above mentioned
rifle scope.
The receiver was quite dumb, all intelligence was on the transmitter
site. The TX equipment generated a PN code that lasted about 1s, and a
full observation cycle lasted about a minute, I don't remember the exact
figures. The code was sent advanced to take care of the round trip light
time but an additional time bias of 30 us was also introduced which was
the basis of the measurement. The bias was decreased 1us/s, so
theoretically it was received just on time in the second 30.
The receiver generated the same PN using the station timing reference
(from a HP 5065A Rb) and it was correlated with the received code. The
output of the correlator was integrated and sent to a strip chart
recorder. The graph consisted in one trace with a quite noisy ramp and
the other trace with 1PPS from the station reference. Now the weird
thing: after finishing an observation, we put the graph in a desk and
using a drafting rule we draw a straight line that tried to be the "best
fit" to the noisy ramp. Were the line crossed the zero we read the PPS
mark there and counting back to the start of the minute we got the PPS
offset with respect to the transmitting station. Of course we averaged
the values obtained from several minutes, after discarding the noisiest
ones.
Since we didn't had any faith in the system we didn't tried to suggest
improvements or improve it ourselves. A good one could be to use a
computer program to perform the best fit analytically, but this would
mean to type the hundreds of points manually from the graph and we never
tried this. There were not a digital version of the output, we also
could use a digital voltmeter for acquiring it. We suggested or
implemented a lot of improvements to other operational things, but this
contraption was felt as a dead horse from the beginning and its
operational life was short. Later it was replaced with a GPS based one:
2 full height racks filled with equipment and an antenna made from a 10
or 20 gallon hermetic paint drum for housing the front end electronics,
topped with a fiberglass radome about 1 1/2 ' in diameter. It was
painted white, but the cylinder origin was discovered during a
maintenance. It was a beautiful prototype that worked very well during
its shot life.
I don't keep pictures of this equipment, but I have one with the same
antenna used for other purposes.
Sorry for the bandwidth, but the thread brought me old memories.
Best regards,
Ignacio
El 23/05/2020 a las 19:17, jimlux escribió:
On 5/23/20 9:18 AM, Mike Millen wrote:
Probably a good idea... there are two page 19s and no page 20 in the
pdf. :-(
That's the page where the aliens came and told us how to build the
DSN, then the story resumes with 26m antenna design and operation.
(If anyone's interested, I can probably ask the librarians to find it
at JPL - correcting the pdf/microfilm is probably beyond scope)
--
El software de antivirus Avast ha analizado este correo electrónico en
busca de virus.
https://www.avast.com/antivirus
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.