Homemade Base Station antenna type

I recently built a working base station using a Mosiac X5 board and a Trimble AG25 antenna. I’ve been delivering NTRIP corrections to a Pro 700/372 and a Trimble FMX successfully for the past month. Yesterday I moved the system to its pernament location and at the same time changed the antenna to an Ardusimple calibrated antenna. It may also be a better antenna? If I tell the X5 it is using the Ardusimpe antenna I do not get corrections on my tractors. If I change it back to the trimble or none it works. Why is this?

Please tell us more about your base setup. My understanding is that X5 does not have an internal NTRIP caster, is that right? If so, which caster are you using?

I thought it could be an incompatible antenna phantom voltage but X5 seems to be able to provide 3 to 5.5 Volts and the Ardusimple calibrated antenna accepts 3 to 12. Perhaps X5 does not recognise the antenna type and switches phantom voltage off to be safe.

Do you mean the rovers do not receive any corrections or do you mean they do not reach RTK fix?

Which RTCM messages do you send from the base, I think the old RTCM1008 incompatibility issue should not matter with MSM messages, I did not check which FMX and Pro 700/372 support.

By the way, would be interesting to know how you decided to purchase X5, are your rovers triple band?

My base setup is extremely simple. It sits on a post 125 ft south of my shop building in an grassy yard. I buried ethernet cable to the location from my shop where there is a POE switch and fiber internet service. At the post is the antenna and a box that has the X5 board along with a POE power/data splitter. The splitter outputs 5v to a USB-C cable. The X5 board also has the Ardusimple Ethernet Shield on it to accept the network connection. I’m outputting an RTCM 3 stream to RTK2GO with messages 1006, 1008, 1033, 1074, 1084, and 1230. My rovers are a Trimble FMX, Pro700/372, and a CaseIH Vector Pro.

Even though I’m telling it I’m using a Trimble Antenna at the moment, I’m really using the Ardusimple antenna. That setting/field is to make sure the correct calibration files with phase centers and offset are used.

I don’t think you need that antenna calibration data for 1 cm accuracy. Not sure if the Trimble data makes it worse than no calibration data at all.

Is the Case GNSS receiver made by Trimble too? Sounds like an issue with the RTCM 1008 content even if I thought you would not need it with MSM messages. Can you use the “ADVNULLANTENNA” definition that we mostly use with RTKBase and F9P receivers when feeding corrections to Trimble receivers?

I’m not familiar with Trimble but there are many real experts onboard who will hopefully help you soon.