Hi Chris, thanks for the feedback... the cost is not a concern, is making the run to the peak of the roof worth it as far as the GPS reception / signal is concerned? Where I have a clean view south, is it worth it to run the coax up through the attic and to the peak of the roof so I get a totally clear 360 view to the north? If not, it's much easier to put my mast mount a few feet back on the eve of the roof.
I have the LMR-400 collecting dust and the RG-213 sized N connectors... so I'll just use what I have handy. Max On Fri, Apr 24, 2015 at 8:39 PM, Chris Albertson <[email protected]> wrote: > What is the problem withplaccing the GPS antenna all the way up on the > roof ridge? If you can get an iron pipe and make short mast and place > the GPS Antenna a few feet above the top of the roof. Run the pipe > through the roof into the attic and run the coax cable inside the > pipe. This way the coax is shielded from the weather and sun and you > have a lifetime installation. > > Was the problem the cost of the cable or the loss in that cable? > Don't worry about it. If cost is the problem then use the double > shield Cable TV cable with the swagger-on F connectors. Yes it is 75 > ohm but this is the cable Trimble recommends. If the run is very > long and there is loss, get either a higher gain antenna or an in-line > amplifier. > > You can work around cost and loss in that cable but you can't work > around antenna location. You do NOT need low-loss LMR cable. RG59 > works. > > > > On Fri, Apr 24, 2015 at 5:59 PM, M. George <[email protected]> > wrote: > > Hello Time Nuts! This is my first post, but I have been lurking about > for > > several weeks now... what started out as a project to find a stable time > > reference for a QS1R I have been running 24x7 for years on the NC7J CW > > Skimmer server has taking me down a whole to obsession after finding time > > nuts and GPSDO information. I now have a clean Trimble TBolt and the > > Lucent RFTG-u REF0/1 ready to roll... not to mention a couple of > Raspberry > > Pi 2's with NTP servers on them setup and ready to accept a PPS signal > from > > my new gizmos! I'm following the path that has been traversed many times > > before and I appreciate all the info that I have already gleaned from the > > time nuts list. > > > > Anyway, I didn't get the TBolt for free form China, but it' s a clean > > machine and seems to be settling down nice after running for a few > days... > > > > Another reason for the post here is related to an installation of a GPS > > antenna on my roof. I have a $38 ePay bullet that I'm going to put up > > tomorrow and make a run of solid conductor LMR-400 to the antenna with a > > nice little J-Pole mount. Or potentially 2 runs for 2 GPS antennas. > > > > I'm lucky to have a southern exposure off the back of house with my ham > > shack in the raised basement right in the south west corner of the house > so > > the new GPS antenna project works out well to keep the coax run short as > > possible to the GPS antenna. (see the pics attached or link at the bottom > > of my verbose post here) > > > > I'm shocked at how well a cheapie mushroom GPS antenna is doing close to > > the back of the house on a broom stick at the moment. Anyway, I know > that > > to even think about being a time nut, I need to get a better location for > > the GPS antenna (two really eventually or a splitter). > > > > I have attached a picture of my house and you can pretty much see my > > options. Do I go up and simply put the antenna on the roof close to the > > edge above the rain gutter or do I take it all the way to the peak of the > > roof where you can see a WX station and dual band antenna? > > > > I realize I can calculate the loss in the extra coax, but I'm more > > concerned about the fact that I have a SteppIR BigIR vertical HF antenna > in > > my back yard and I run power / 1KW+ at times on HF (I'm a CW nut!). The > > coax run to the top of the eve is going to be about 30-40 feet of coax > > roughly, if I take it all the way to the peak that's probably another 30 > > feet or so. 70-80 feet max if I go to the roof. > > > > Would a true time-nut need to have the bullet antenna at the peak of the > > root for a true clear view of the horizon even to the north 360 degrees? > > Will it bug me down the road that I didn't just run the bullet / coax up > to > > the peak of the roof down the road, regardless of my concerns about RF > from > > my HF operating potentially getting into the GPS antenna? (I'll probably > > put a voltage limiter on the GPS feed line). The antenna has a nice > direct > > southern view off the eve. > > > > Thoughts for a first time poster and time-nut wanna be? The eve or the > > peak? > > > > Here is a link to the house pic and a few pictures of the TBolt gizmo > that > > arrived from China this week: > http://www.nc7j.com/downloads/NG7M/Time-Nuts/ > > > > I attached the pics too... is that okay on the time nut list? Picture > > attachments? > > > > Max NG7M > > > > > > > > -- > > M. George > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > 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 -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- M. George _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
