Delay through GPS antenna splitter/amplifier -- an answer, and a question
Jason,
Loss in the cable will be in the range of 5 - 7 dB plus connector losses.
Let's say about 10dB max.
Looks OK to me.
Good luck!!!
Rob
----- Original Message -----
From: "Jason Rabel" jason@extremeoverclocking.com
To: "'Discussion of precise time and frequency measurement'"
time-nuts@febo.com
Sent: Monday, March 19, 2007 6:41 PM
Subject: Re: [time-nuts] GPS Signal Strength Through Roof?
Rob,
I was just going to use some RG-58, and if I can mount it in the attic
then
I probably won't need to run more than 15-20ft at most. Loss along the
cable
should be minimal since the run will be short, I just didn't know how much
the roof would block the signal.
Jason
Jason,
I'm using 4 VIC-100s inside, under a flat concrete roof in my single story
office. Tracking 8 satellites on each receiver module on both my CommSync
units. Each one connected to Rx via a coiled up 50 ft length of RG-59.
Yours should work OK. What cable and what length are you planning on
using?
Temp specs on my antennae are -40 to +85C operating which is typical for
this type of product. Don't think it gets that hot in Houston!!
Cheers
Rob K
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Hi,
Just for any UK lurkers, GL also sell in the UK and I've bought from them. There are a few issues,
1 Very poor descriptions a photo of a cardboard box doesn't tell yell you much!
2 Tender only, not an auction, so you really need to know how much you want to pay. There is no way of knowing what the lot finally sold for unless you win it. They do have minimums, sometimes listed, sometimes your bid is just rejected.
3 Viewing is a pain
4 payment and collection deadlines are a pain, all biased to their convenience.
5 Items "disappear" from lots, if you argue they sometimes reappear, sometimes not. If you use a collection agent it's a lucky dip.
6 Items get pulled after you spent time and money viewing them.
7 Lot sizes vary from one worthless metal bracket with a £50 minimum to 10 tons of scrap metal with a couple of nice bits of T&M thrown in. Lot descriptions on size and weight can be inaccurate.
Generally it's hardly worth the bother, I think a few dealers, scrap merchants and people with time on their hands who are local to the Sale site do OK but otherwise I think they need to improve the service.
Robert.
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On Behalf Of Brooke Clarke
Sent: 19 March 2007 17:57
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Government Liquidation
Hi Jason:
I don't recommend GL as a source unless:
- you understand the exact meaning of the Condition Codes, and
- you physically go to the location and preview the lot, and
- you know the product you are looking at, and
- you have the self control to not get into a bidding war (no sniping,
they just extend the closing time), and - you personally pick up the items, and
- you're willing to gamble that you won't have to return any or all of
what you purchased.
If you fail at any step then there's a chance you'll end up with junk,
something else or nothing. Maybe they get some of this stuff from a
dumpster.
With diligence it's possible to overcome the first 5 provisos, but the
last one can be a problem. On more than one occasion GL has mistakenly
sold an item that was not supposed to be sold. In that case the
government (not GL) comes and get the items. If they required an End
User Certificate then you are on the hook to account for all items
including the contact information of any buyers. If you sold an item
your buyer will expect a refund from you. You may expect a refund from
GL, but how long you wait for it is not specified.
The same problem exists with eBay. In my case after purchasing and
receiving a GPS receiver I was contacted by the DOD and they sent a
couple of people to my house to collect the GPS receiver and gave me a
receipt. I got to sign a chain of evidence form to be used at the trial
of the eBay seller on his way to jail. I'm out what I paid. After the
trial I'm free to sue the seller.
Although I'm signed up and have the EUC, I no longer even look at the
auctions with the intent of buying anything. I do use GL to see what's
being sold.
Have Fun,
Brooke Clarke
w/Java http://www.PRC68.com
w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml
http://www.precisionclock.com
Jason Rabel wrote:
This is kind of on the same topic as the government surplus chit-chat...
Just curious but has anyone bought stuff from the website:
????
I just started looking at it last night, they have a ton of stuff and right
now everything has zero bids. I don't know if people all snipe at the last
second or what.
Thoughts / Opinions?
Jason
time-nuts mailing list
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https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Genetix Limited - Queensway, New Milton, Hampshire, BH25 5NN Registered in England No. 2660050 www.genetix.com
Any opinions expressed in this email are those of the individual and not necessarily Genetix Ltd (Genetix) or any company associated with it. This email and any files transmitted with it are confidential and solely for the use of the intended recipient. If you are not the intended recipient or the person responsible for delivering to the intended recipient, be advised that you have received this email in error and that any use is strictly prohibited. If you have received this email in error please notify Genetix by telephone on +44 (0)1425 624600.
The unauthorised use, disclosure, copying or alteration of this message is strictly forbidden. This mail and any attachments have been scanned for viruses prior to leaving Genetix network. Genetix will not be liable for direct, special, indirect or consequential damages as a result of any virus being passed on, or arising from alteration of the contents of this message by a third party.
Thanks for the info. I won't be bothering - my time is precious!!
:-))
Rob (in the UK)
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Robert Atkinson
Sent: 20 March 2007 09:02
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Government Liquidation
Hi,
Just for any UK lurkers, GL also sell in the UK and I've bought from them.
There are a few issues,
1 Very poor descriptions a photo of a cardboard box doesn't tell yell you
much!
2 Tender only, not an auction, so you really need to know how much you want
to pay. There is no way of knowing what the lot finally sold for unless you
win it. They do have minimums, sometimes listed, sometimes your bid is just
rejected.
3 Viewing is a pain
4 payment and collection deadlines are a pain, all biased to their
convenience.
5 Items "disappear" from lots, if you argue they sometimes reappear,
sometimes not. If you use a collection agent it's a lucky dip.
6 Items get pulled after you spent time and money viewing them.
7 Lot sizes vary from one worthless metal bracket with a £50 minimum to 10
tons of scrap metal with a couple of nice bits of T&M thrown in. Lot
descriptions on size and weight can be inaccurate.
Generally it's hardly worth the bother, I think a few dealers, scrap
merchants and people with time on their hands who are local to the Sale site
do OK but otherwise I think they need to improve the service.
Robert.
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Brooke Clarke
Sent: 19 March 2007 17:57
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Government Liquidation
Hi Jason:
I don't recommend GL as a source unless:
- you understand the exact meaning of the Condition Codes, and
- you physically go to the location and preview the lot, and
- you know the product you are looking at, and
- you have the self control to not get into a bidding war (no sniping, they
just extend the closing time), and - you personally pick up the items, and
- you're willing to gamble that you won't have to return any or all of what
you purchased.
If you fail at any step then there's a chance you'll end up with junk,
something else or nothing. Maybe they get some of this stuff from a
dumpster.
With diligence it's possible to overcome the first 5 provisos, but the last
one can be a problem. On more than one occasion GL has mistakenly sold an
item that was not supposed to be sold. In that case the government (not GL)
comes and get the items. If they required an End User Certificate then you
are on the hook to account for all items including the contact information
of any buyers. If you sold an item your buyer will expect a refund from
you. You may expect a refund from GL, but how long you wait for it is not
specified.
The same problem exists with eBay. In my case after purchasing and
receiving a GPS receiver I was contacted by the DOD and they sent a couple
of people to my house to collect the GPS receiver and gave me a receipt. I
got to sign a chain of evidence form to be used at the trial of the eBay
seller on his way to jail. I'm out what I paid. After the trial I'm free
to sue the seller.
Although I'm signed up and have the EUC, I no longer even look at the
auctions with the intent of buying anything. I do use GL to see what's
being sold.
Have Fun,
Brooke Clarke
w/Java http://www.PRC68.com
w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml
http://www.precisionclock.com
Jason Rabel wrote:
This is kind of on the same topic as the government surplus chit-chat...
Just curious but has anyone bought stuff from the website:
????
I just started looking at it last night, they have a ton of stuff and
right now everything has zero bids. I don't know if people all snipe at
the last second or what.
Thoughts / Opinions?
Jason
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Genetix Limited - Queensway, New Milton, Hampshire, BH25 5NN Registered in
England No. 2660050 www.genetix.com
Any opinions expressed in this email are those of the individual and not
necessarily Genetix Ltd (Genetix) or any company associated with it. This
email and any files transmitted with it are confidential and solely for the
use of the intended recipient. If you are not the intended recipient or the
person responsible for delivering to the intended recipient, be advised that
you have received this email in error and that any use is strictly
prohibited. If you have received this email in error please notify Genetix
by telephone on +44 (0)1425 624600.
The unauthorised use, disclosure, copying or alteration of this message is
strictly forbidden. This mail and any attachments have been scanned for
viruses prior to leaving Genetix network. Genetix will not be liable for
direct, special, indirect or consequential damages as a result of any virus
being passed on, or arising from alteration of the contents of this message
by a third party.
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Hi I am new to this group, my background; electronics, amateur radio
and clocks.
I am developing a free pendulum and to analyse its operation I
compare it to WWV
on 5 or 10 MHz, the only available radio frequency standard on air in
Australia.
To examine the phase drift and jitter I compare it with a 1MHz rock
in an oven.
I have a HP 5328A which is not stable. It is marked as having option 010
but when I look inside there is only one crystal, 10mhz, which looks
like an el cheapo,
and no sign of an oven.
Can anyone tell me what option 010 looks like?
I intend to buy a $20, better than average, 10mhz rock and put it in
an oven.
Any advice would be appreciated,
Neville Michie
Here is a link to a photo of an HP 10811
http://www.slack.com/images/TE/HP10811A.jpg
Jamie
--- Neville Michie namichie@gmail.com wrote:
Hi I am new to this group, my background;
electronics, amateur radio
and clocks.
I am developing a free pendulum and to analyse its
operation I
compare it to WWV
on 5 or 10 MHz, the only available radio frequency
standard on air in
Australia.
To examine the phase drift and jitter I compare it
with a 1MHz rock
in an oven.
I have a HP 5328A which is not stable. It is marked
as having option 010
but when I look inside there is only one crystal,
10mhz, which looks
like an el cheapo,
and no sign of an oven.
Can anyone tell me what option 010 looks like?
I intend to buy a $20, better than average, 10mhz
rock and put it in
an oven.
Any advice would be appreciated,
Neville Michie
time-nuts mailing list
time-nuts@febo.com
Fedora Core 4 Linux
8:00? 8:25? 8:40? Find a flick in no time
with the Yahoo! Search movie showtime shortcut.
http://tools.search.yahoo.com/shortcuts/#news
It looks like this
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280095458978
If it doesn't look very similar to this, buy this one and have done with it!
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Neville Michie
Sent: Tuesday, March 20, 2007 7:28 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Hello
Hi I am new to this group, my background; electronics, amateur radio
and clocks.
I am developing a free pendulum and to analyse its operation I
compare it to WWV
on 5 or 10 MHz, the only available radio frequency standard on air in
Australia.
To examine the phase drift and jitter I compare it with a 1MHz rock
in an oven.
I have a HP 5328A which is not stable. It is marked as having option 010
but when I look inside there is only one crystal, 10mhz, which looks
like an el cheapo,
and no sign of an oven.
Can anyone tell me what option 010 looks like?
I intend to buy a $20, better than average, 10mhz rock and put it in
an oven.
Any advice would be appreciated,
Neville Michie
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Neville,
I am old to this group. I remember when we could go for days
without a message. My background is BSME in 1960, lifetime
interest in electronics and computing (tho I don't write code
anymore) applied to chemical process control. Always interested
in precision time, intensified after a visit to Greenwich and
the British Science Museum's exhibit on clocks.
The Shortt pendulum was of great interest - what could 70 years
of relentlessly advancing technology have to improve on it?
That is a top priority, behind consulting commitments, financial
management, home maintenance, building computers and looking for
business. Which is to say, I've bought things but haven't had any
time to do anything with them, like the Invar rod.
Many years later, I've been able to buy much more than I've been
able to do. My dear and patient wife wants to know when she will
be able to move about the basement again. We approach 70 now, so
it's not like we'll be searching for alternative partners.
But I digress. My research has shown that a free pendulum would be
doing well to approach 10E-8 in accuracy. The folks on this list
are going for 10E-12.
Can you afford a GPS disciplined receiver, like the HP Z3801? That
is all the accuracy you will ever need, better that 10E-10. Crystals
(undisciplined) do not go that low. Satellites do fly over Oz, no?
I no longer think that I will assemble a vacuum pump, tube, zero-loss
pivot, and electrostatic detection and excitation mechanisms in my
lifetime. Especially since I live 100 meters from a low-speed freight
railroad track. Pity, really. Too soon old, too late smart.
Hope I haven't depressed you.
Best regards,
Bill Hawkins
P.S. Visited Melbourne and Sydney, crossing the bridge on foot, in the
mid 80's. Went to Healsville in a 60 MPH wind, unforgettable. Joeys not
just standing around. Got back from a rainy visit to the Fairy Penguins,
no lights in the bathroom or shower, called the desk, "No worries, mate.
The electrician will set it straight in the morning."
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Neville Michie
Sent: Tuesday, March 20, 2007 7:28 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Hello
Hi I am new to this group, my background; electronics, amateur radio and
clocks.
I am developing a free pendulum and to analyse its operation I compare
it to WWV on 5 or 10 MHz, the only available radio frequency standard on
air in Australia.
To examine the phase drift and jitter I compare it with a 1MHz rock in
an oven.
I have a HP 5328A which is not stable. It is marked as having option 010
but when I look inside there is only one crystal, 10mhz, which looks
like an el cheapo, and no sign of an oven.
Can anyone tell me what option 010 looks like?
I intend to buy a $20, better than average, 10mhz rock and put it in an
oven.
Any advice would be appreciated,
Neville Michie
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Hello!
It looks like this
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280095458978
If it doesn't look very similar to this, buy this one and have done with it!
I have got some HP units with that kind of oscillator instead of the
'original' HP unit... I wonder if this was an aftermarket cheaper option
(my guess) or if HP ever provided it (don't think so!)
Regards,
JOSE
73 EB5AGV / EC5AAU - JOSE V. GAVILA
La Canyada - Valencia (SPAIN) - Loc: IM99SM
Vintage Radio: http://jvgavila.com
Vintage Test Equipment: http://jvgavila.com/testeq.htm
European Boatanchors List: http://groups.yahoo.com/group/euro_ba_swap
The Shortt pendulum was of great interest - what could 70 years
of relentlessly advancing technology have to improve on it?
That is a top priority, behind consulting commitments, financial
management, home maintenance, building computers and looking for
business. Which is to say, I've bought things but haven't had any
time to do anything with them, like the Invar rod.
I would be interested if others of you time-nuts are also
involved with pendulum clocks. At the surface it might
seem odd that with today's technology that anyone would
want to spend time with pendulum clocks. But there are
several hundred guys around the world who are spending
a great deal of time working on modern pendulum clocks.
The history, science, and technology of these things is
far, far deeper than you might think. Here I can make a
plug for Jim's website:
http://www.clockvault.com/heritage/index.htm
and also have a look at Bill's amazing creations:
http://www.precisionclocks.com/
I really like my cesium clocks, but you've got to admit
these old (Riefler and Shortt) and new (Q1 and Q2)
are much better eye candy and old HP or FTS clock.
Many years later, I've been able to buy much more than I've been
able to do. My dear and patient wife wants to know when she will
be able to move about the basement again. We approach 70 now, so
it's not like we'll be searching for alternative partners.
But I digress. My research has shown that a free pendulum would be
doing well to approach 10E-8 in accuracy. The folks on this list
are going for 10E-12.
Right, the best ADEV you can do with a pendulum clock
is about 5e-9 for a tau on the order of days. I should send
you the plots.
I no longer think that I will assemble a vacuum pump, tube, zero-loss
pivot, and electrostatic detection and excitation mechanisms in my
lifetime. Especially since I live 100 meters from a low-speed freight
railroad track. Pity, really. Too soon old, too late smart.
Yes, others working with pendulums have also discovered
that they end up making crude thermometers, barometers,
or seismometers instead of a good clock. Still, not a reason
to give up. But you know you have a world-class pendulum
clock when, after having solved every other perturbation, you
can see the effects of lunar tides in your data (as your good
pendulum clock demonstrates it is also a fair gravimeter).
Tom Van Baak wrote:
The Shortt pendulum was of great interest - what could 70 years
of relentlessly advancing technology have to improve on it?
That is a top priority, behind consulting commitments, financial
management, home maintenance, building computers and looking for
business. Which is to say, I've bought things but haven't had any
time to do anything with them, like the Invar rod.
I would be interested if others of you time-nuts are also
involved with pendulum clocks. At the surface it might
seem odd that with today's technology that anyone would
want to spend time with pendulum clocks. But there are
several hundred guys around the world who are spending
a great deal of time working on modern pendulum clocks.
The history, science, and technology of these things is
far, far deeper than you might think. Here I can make a
plug for Jim's website:
http://www.clockvault.com/heritage/index.htm
and also have a look at Bill's amazing creations:
http://www.precisionclocks.com/
I really like my cesium clocks, but you've got to admit
these old (Riefler and Shortt) and new (Q1 and Q2)
are much better eye candy and old HP or FTS clock.
Stuff snipped
There was a series of articles in The Home Shop Machinist starting in the
September/October 2000 issue that described construction of a Free
Pendulum clock
I think I can find all of the articles if some one wants them
Bill K7NOM (not really nutty about time)