I currently use a Grass Valley Group 8802 video distribution amp (DA). Yes they start to roll-off the frequency at 6 MHz but the roll-off is gradual and it will certianly pass 10 MHz with no problem. Remember you are not passing multple frequencies or multi-burst, just 10 MHz. Also, these DAs are designed be unity gain and to handle approximately 1 volt p-p so be carefull of clipping if you drive much more than that level or alternatively, pad down the input to a 1 volt level.
From: "time-nuts-requ...@febo.com" <time-nuts-requ...@febo.com> To: time-nuts@febo.com Sent: Tuesday, August 21, 2012 1:00 PM Subject: time-nuts Digest, Vol 97, Issue 63 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than "Re: Contents of time-nuts digest..." Today's Topics: 1. Re: Thunderbolt distribution amplifier needed (Chris Albertson) 2. Re: Thunderbolt distribution amplifier needed (Pete Lancashire) 3. Re: Thunderbolt distribution amplifier needed (paul swed) 4. Re: : L1 GPS timing signal(s) into local time oncomputer(s) (Bill Hawkins) 5. Maker Faire Sept 29 & 30 NY Hall of Science (MITCHELL JANOFF) 6. Re: : L1 GPS timing signal(s) into local time on computer(s) (Hal Murray) ---------------------------------------------------------------------- Message: 1 Date: Tue, 21 Aug 2012 09:54:14 -0700 From: Chris Albertson <albertson.ch...@gmail.com> To: "BD Systems Inc." <bdsy...@yahoo.com>, Discussion of precise time and frequency measurement <time-nuts@febo.com> Subject: Re: [time-nuts] Thunderbolt distribution amplifier needed Message-ID: <cabbxvhtkvh5wixxzoeyo2-nv51ev2vnrsbapaoj851-pyda...@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 I bought a eBay video distribution amp. The bandwidth was not as good as I liked but for some reason the opamps were run off +/- 12 volts. Raising the power to +/- 18V greatly improved the performance of the amp. Many video amp assume the signal to 6MHz bandwidth might not be ideal. But on the other hand some old studio equipment is grossly over engineered and might be very good for 10Mhz distribution. The good news is the today analog video amps are cheap as dirt as no one wants analog video. On Tue, Aug 21, 2012 at 7:17 AM, BD Systems Inc. <bdsy...@yahoo.com> wrote: > Use an analog video distribution amplifier (Grass Valley Group, Leitch, > Ross Video etc). These have between 6 to 8 outputs and will provide a > reference to various test equipment. > > > From: "time-nuts-requ...@febo.com" <time-nuts-requ...@febo.com> > To: time-nuts@febo.com > Sent: Tuesday, August 21, 2012 6:00 AM > Subject: time-nuts Digest, Vol 97, Issue 60 > > Send time-nuts mailing list submissions to > time-nuts@febo.com > > To subscribe or unsubscribe via the World Wide Web, visit > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > or, via email, send a message with subject or body 'help' to > time-nuts-requ...@febo.com > > You can reach the person managing the list at > time-nuts-ow...@febo.com > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of time-nuts digest..." > > > Today's Topics: > > 1. Thunderbolt distribution amplifier needed. (Chris Wilson) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Tue, 21 Aug 2012 11:44:17 +0100 > From: Chris Wilson <ch...@chriswilson.tv> > To: "time-nuts@febo.com" <time-nuts@febo.com> > Subject: [time-nuts] Thunderbolt distribution amplifier needed. > Message-ID: <5746920.20120821114...@chriswilson.tv> > Content-Type: text/plain; charset=windows-1252 > > > > 21/08/2012 11:40 > > Can anyone please link specifically to a suitable distribution amp for > my TB please, either here if it's allowed, or by e-mail to me at > ch...@chriswilson.tv ? Cost is a factor, and I am in the UK. An Ebay > purchase would be painless. I feel it would be really easy for someone > as daft as me to buy something totally unsuitable. I want to run David > Partridge's divider board and have enough 10MHz signalleft to run other > stuff as well, David recommended I run the amp between the TB and his > divider. Cheers. > > -- > Best Regards, > Chris Wilson. > mailto: ch...@chriswilson.tv > > > > > ------------------------------ > > _______________________________________________ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > End of time-nuts Digest, Vol 97, Issue 60 > ***************************************** > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Chris Albertson Redondo Beach, California ------------------------------ Message: 2 Date: Tue, 21 Aug 2012 10:12:27 -0700 From: Pete Lancashire <p...@petelancashire.com> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Cc: "BD Systems Inc." <bdsy...@yahoo.com> Subject: Re: [time-nuts] Thunderbolt distribution amplifier needed Message-ID: <caa-f0u9nkye77osz_9cdogctrkfyksa6iqjyvfg2fljzavc...@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 It all depends on the brand and if 'commercial' or not. A Grass Valley (dont remember the model) tested is 3db down starting around 25 MHz. I have also seen others that have a LP filter option installed on the input module. -pete On Tue, Aug 21, 2012 at 9:54 AM, Chris Albertson <albertson.ch...@gmail.com> wrote: > I bought a eBay video distribution amp. The bandwidth was not as good as > I liked but for some reason the opamps were run off +/- 12 volts. Raising > the power to +/- 18V greatly improved the performance of the amp. Many > video amp assume the signal to 6MHz bandwidth might not be ideal. But on > the other hand some old studio equipment is grossly over engineered and > might be very good for 10Mhz distribution. The good news is the today > analog video amps are cheap as dirt as no one wants analog video. > > > > > On Tue, Aug 21, 2012 at 7:17 AM, BD Systems Inc. <bdsy...@yahoo.com> wrote: > >> Use an analog video distribution amplifier (Grass Valley Group, Leitch, >> Ross Video etc). These have between 6 to 8 outputs and will provide a >> reference to various test equipment. >> >> >> From: "time-nuts-requ...@febo.com" <time-nuts-requ...@febo.com> >> To: time-nuts@febo.com >> Sent: Tuesday, August 21, 2012 6:00 AM >> Subject: time-nuts Digest, Vol 97, Issue 60 >> >> Send time-nuts mailing list submissions to >> time-nuts@febo.com >> >> To subscribe or unsubscribe via the World Wide Web, visit >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> or, via email, send a message with subject or body 'help' to >> time-nuts-requ...@febo.com >> >> You can reach the person managing the list at >> time-nuts-ow...@febo.com >> >> When replying, please edit your Subject line so it is more specific >> than "Re: Contents of time-nuts digest..." >> >> >> Today's Topics: >> >> 1. Thunderbolt distribution amplifier needed. (Chris Wilson) >> >> >> ---------------------------------------------------------------------- >> >> Message: 1 >> Date: Tue, 21 Aug 2012 11:44:17 +0100 >> From: Chris Wilson <ch...@chriswilson.tv> >> To: "time-nuts@febo.com" <time-nuts@febo.com> >> Subject: [time-nuts] Thunderbolt distribution amplifier needed. >> Message-ID: <5746920.20120821114...@chriswilson.tv> >> Content-Type: text/plain; charset=windows-1252 >> >> >> >> 21/08/2012 11:40 >> >> Can anyone please link specifically to a suitable distribution amp for >> my TB please, either here if it's allowed, or by e-mail to me at >> ch...@chriswilson.tv ? Cost is a factor, and I am in the UK. An Ebay >> purchase would be painless. I feel it would be really easy for someone >> as daft as me to buy something totally unsuitable. I want to run David >> Partridge's divider board and have enough 10MHz signalleft to run other >> stuff as well, David recommended I run the amp between the TB and his >> divider. Cheers. >> >> -- >> Best Regards, >> Chris Wilson. >> mailto: ch...@chriswilson.tv >> >> >> >> >> ------------------------------ >> >> _______________________________________________ >> time-nuts mailing list >> time-nuts@febo.com >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> >> End of time-nuts Digest, Vol 97, Issue 60 >> ***************************************** >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > > -- > > Chris Albertson > Redondo Beach, California > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ------------------------------ Message: 3 Date: Tue, 21 Aug 2012 13:20:05 -0400 From: paul swed <paulsw...@gmail.com> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Subject: Re: [time-nuts] Thunderbolt distribution amplifier needed Message-ID: <CAD2JfAjbi0bPxzO6f+=CqvhsJtvNJbid2_bXjWi1U4X2R=r...@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Exactly right on many of the accounts. The oldest DAs may be 6 Mhz but I am not sure you will even find them any longer. The more modern preHDTVs were all easily in the 10-30 Mhz region. Most have eq adjustments so that you could peak for the higher frequency like 10 Mhz. Boy the amps and chassis are cheap these days. Stay clear of more complicated DAs like delay if possible. Just lots of stuff to add noise and lots of little jumpers to change. Picked up 2 trays of GVG 8500 class DAs for $30 each. They are junk actually these days. So most are headed to the dumpsters. Regards Paul On Tue, Aug 21, 2012 at 12:54 PM, Chris Albertson <albertson.ch...@gmail.com > wrote: > I bought a eBay video distribution amp. The bandwidth was not as good as > I liked but for some reason the opamps were run off +/- 12 volts. Raising > the power to +/- 18V greatly improved the performance of the amp. Many > video amp assume the signal to 6MHz bandwidth might not be ideal. But on > the other hand some old studio equipment is grossly over engineered and > might be very good for 10Mhz distribution. The good news is the today > analog video amps are cheap as dirt as no one wants analog video. > > > > > On Tue, Aug 21, 2012 at 7:17 AM, BD Systems Inc. <bdsy...@yahoo.com> > wrote: > > > Use an analog video distribution amplifier (Grass Valley Group, Leitch, > > Ross Video etc). These have between 6 to 8 outputs and will provide a > > reference to various test equipment. > > > > > > From: "time-nuts-requ...@febo.com" <time-nuts-requ...@febo.com> > > To: time-nuts@febo.com > > Sent: Tuesday, August 21, 2012 6:00 AM > > Subject: time-nuts Digest, Vol 97, Issue 60 > > > > Send time-nuts mailing list submissions to > > time-nuts@febo.com > > > > To subscribe or unsubscribe via the World Wide Web, visit > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > or, via email, send a message with subject or body 'help' to > > time-nuts-requ...@febo.com > > > > You can reach the person managing the list at > > time-nuts-ow...@febo.com > > > > When replying, please edit your Subject line so it is more specific > > than "Re: Contents of time-nuts digest..." > > > > > > Today's Topics: > > > > 1. Thunderbolt distribution amplifier needed. (Chris Wilson) > > > > > > ---------------------------------------------------------------------- > > > > Message: 1 > > Date: Tue, 21 Aug 2012 11:44:17 +0100 > > From: Chris Wilson <ch...@chriswilson.tv> > > To: "time-nuts@febo.com" <time-nuts@febo.com> > > Subject: [time-nuts] Thunderbolt distribution amplifier needed. > > Message-ID: <5746920.20120821114...@chriswilson.tv> > > Content-Type: text/plain; charset=windows-1252 > > > > > > > > 21/08/2012 11:40 > > > > Can anyone please link specifically to a suitable distribution amp for > > my TB please, either here if it's allowed, or by e-mail to me at > > ch...@chriswilson.tv ? Cost is a factor, and I am in the UK. An Ebay > > purchase would be painless. I feel it would be really easy for someone > > as daft as me to buy something totally unsuitable. I want to run David > > Partridge's divider board and have enough 10MHz signalleft to run other > > stuff as well, David recommended I run the amp between the TB and his > > divider. Cheers. > > > > -- > > Best Regards, > > Chris Wilson. > > mailto: ch...@chriswilson.tv > > > > > > > > > > ------------------------------ > > > > _______________________________________________ > > time-nuts mailing list > > time-nuts@febo.com > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > End of time-nuts Digest, Vol 97, Issue 60 > > ***************************************** > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > -- > > Chris Albertson > Redondo Beach, California > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ------------------------------ Message: 4 Date: Tue, 21 Aug 2012 13:10:34 -0500 From: "Bill Hawkins" <b...@iaxs.net> To: "'Discussion of precise time and frequency measurement'" <time-nuts@febo.com> Subject: Re: [time-nuts] : L1 GPS timing signal(s) into local time oncomputer(s) Message-ID: <AD2ABF12D68C4AFBA3309199259D50DE@cyrus> Content-Type: text/plain; charset="us-ascii" The importance of cable delay depends on what you are doing with the time. If you are taking data in remote locations with different GPS receivers, then cable delay is necessary to correlate the results in time. See the recent mail on FTL neutrinos. If you are being NTP Stratum 0 to one network (please don't assert NTP Stratum 0 to the Internet with a rig put together from eBay parts), then the cable delay is a miniscule phase shift between you and reality. Bill Hawkins -----Original Message----- From: Sarah White Sent: Tuesday, August 21, 2012 11:53 AM Wow. Okay. The user manual actual considers this cable delay to be worth mention? I can see why the trimble thunderbolt is a favorite among time nuts <3 I'm sold. ------------------------------ Message: 5 Date: Tue, 21 Aug 2012 11:27:35 -0700 (PDT) From: MITCHELL JANOFF <majan...@verizon.net> To: "time-nuts@febo.com" <time-nuts@febo.com> Subject: [time-nuts] Maker Faire Sept 29 & 30 NY Hall of Science Message-ID: <1345573655.14099.yahoomail...@web84508.mail.ne1.yahoo.com> Content-Type: text/plain; charset=iso-8859-1 I'm working on a "Time-Nuts" based exhibit at the 2012 MakerFaire in NYC (http://makerfaire.com/newyork/2012/). The idea is the history of time distribution with a focus on modern timekeeping (1900 to the present). It is a non-commercial booth, focused on education, and?demonstrating micro-processing technology and timekeeping. I plan to bring a couple of atomic clocks, various WWV and WWVB receivers,?an oscilloscope and GPS devices?that I've connected to microprocessors to display the time and also synchronize clocks from the Self Winding Clock Company of NY. My application has been accepted and I'm now working on the actual exhibit. If there is anyone in the NYC area that would like to collaborate on this project, please contact me via email. Any suggestions for the exhibit are appreciated.? ? Thanks.? ------------------------------ Message: 6 Date: Tue, 21 Aug 2012 12:00:00 -0700 From: Hal Murray <hmur...@megapathdsl.net> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Subject: Re: [time-nuts] : L1 GPS timing signal(s) into local time on computer(s) Message-ID: <20120821190000.96d0c800...@ip-64-139-1-69.sjc.megapath.net> Content-Type: text/plain; charset=us-ascii kuze...@gmail.com said: > ... I would presume that the fixed location used for above calculations > would be relative to the position of the antenna? A side effect of figuring out where you are is figuring out when you are there. There are 4 unknowns: X, Y, Z, T, so you need 4 equations. You get one equation from each satellite so you need 4 satellites. If you assume you are on the surface of the earth, you can get away with only 3 satellites. Yes, that tells you where the antenna is located. If you know where you are, you only need 1 satellite to get the time. > I read somewhere that even compensating for the length of the > antenna cabling is important? > Wow. Okay. The user manual actual considers this cable delay to be worth > mention? Sure. The speed of light in air/vacuum is 1 ft/ns. Coax (and fiber) is slower. Junk coax is roughly half as fast. Good coax (foam) is roughly 2/3rds as fast. So it's easy to get 100 ns but unlikely to get more than a microsecond on an amateur budget. Whether that is important for you depends upon your application and the length of the antenna cable. With a modern not super-expensive scope, it's easy to see 1 ns offsets, so cable lengths could be important on something as simple as comparing the PPS outputs from 2 GPS systems. Don't forget to consider the lengths of other cables in your setup. I remember getting an interesting lesson in this area many years ago. We had a couple of scope probes with long cables. I was using one long one and one normal one and looking at high speed digital signals. The offset was enough to confuse me. -- These are my opinions. I hate spam. ------------------------------ _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts End of time-nuts Digest, Vol 97, Issue 63 ***************************************** _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.