Does anyone have more information on the advice below on setting up GPS receiver on a tripod.
It is recommended for integrated antenna/receivers that an extension pole is used to lift the antenna clear of the tripod.
I am curious what the reason for this is?
Thanks
We included a bar so the UHF antenna will clear the tribrach. It somewhat helps radio range to have the UHF antenna clear of the tribrach, even if it clears it on the side.
Those pictures are interesting because they show the UHF antenna extending above the GNSS antenna. You should avoid this, unless you can place the UHF antenna directly to the north of the GNSS antenna.
The UHF antenna will 'break' the path between the SV and the GNSS antenna and plays havoc as SV's rise and set through the path of the antenna. With lots of SV's, it may not always make a difference, but you don't want to cripple your rover with crappy corrections needlessly.
M
Try it without the extender and you'll find out.
First, the radio antenna gets bent over by the tribrach puck.
Second, there isn't room to get an external power cable into the lemo connector with the base of the receiver smashed against the tribrach puck.
>UHF antenna extending above the GNSS antenna. You should avoid this, unless you can place the UHF antenna directly to the north of the GNSS antenna.
Unless you have data showing that it has negligible effect when north, I'd try very hard to keep the UHF antenna clear of the GNSS antenna. I can imagine it affecting the results no matter which side it was on, if above.
Ah I see - I don't have the antenna or external power attached.
I have had used it without the extension before, I was curious what is "wrong" with not using it.
I was reading "GPS antenna" for "radio antenna" in the original article.
I definitely prefer using a 0.25m pole on the fixed height when setting up an R8. Even if you don't need to access any of the ports it's a bad fit without it. It's supposed to be mandatory for our crews but I still come across guys in the field who don't have one...
> Of course nearly anything can prove to be a multi-path hazard (though the profile of that skinny little antenna maybe not so much). If it did, it might be so deep in the typical noise as to not be independently detectable.
Thanks for the response, are you saying that it the multipath would be filtered out by the receiver as noise, or that it wouldn't be able to spot it?
Reason I ask is that I am setting up a base station on the roof of our site cabins. There is already a 2 way radio antenna (for walkie-talkies) mounted on a 2 inch steel tube. This projects above the roof level about 3m. I am planning on putting the GPS antenna just at roof level.
I can mount the GPS antenna about 10m away from the radio antenna so I am hoping that this is far enough away that any multipath caused would be minimal and easily spotted by the receiver.
I am also wondering if the roof of the office (sheet metal) cause multipath and would elevating the GPS antenna help with this?
The antenna will be a Zephyr 2 Geodetic (big one same as the photo I think). The receiver is a Trimble SPS855
brilliant, thanks for the advice
> The RF of the radio antenna... no, it does not typically harm the GNSS side.
According to Javad Ashjaee:
> There is no hard rule. The effect depends on the power of the transmitter. Vertical or horizontal separation is the same. The further you are the effect is less. For 1 watt stay away a few feet. For 45 watt, stay away 20 feet. The further the better.
