Base station to N-trip

[AlanT]

We run our Topcon steering systems off our own RTK base station but have recently put SIM cards in to work on Ntrip for when we get out of range from our base.
Do I need to change the receiver aerial on the tractor?
Am I right in thinking it’s been picking radio waves up from our base but now it has to pick up cell data?
When looking at the phone signal strength on the screen it’s very up and down, anywhere between 2 and 5 bars and it can often loose RTK signal but still has 4 bar strength.
The tractor working next to me keeps its full signal strength all the time but has a Novotel Fendt system in. This did have a different aerial fitted when Fendt changed it to ntrip.

 

[Northern farmer]

Is it the Topcon AGI-4 receiver? You should have a different antenna for cellular frequencies (NTRIP) and for the radio.

 

[Richard Smyth]

I have used mine with the original 450 MHz antennae which worked but not advisable I’ve changed it to a cellular antennae and it’s much better. I’m amazed at where I can get ntrip coverage. It’s reliable up to 100 km from my base station also.

topcon agi4 or Agco ag3000 whatever you want to call it

 

[AlanT]

It’s an AGI-3. Sounds like I need to look for a cellular antenna then.

 

[peachmelba]

I have a X30 with a AGI-4. LH Agro have just done an update ( end of warranty) and my RTK went to being almost unusable. So trying a SIM (GPS) to a mast less than 1 mile away. Was ok but only get 3 bars on X30 screen. So we have changed the antenna to a proper GPS. Its a little better but had use the TopNet signal as more reliable. Even with that i only get a max of 4 bars even with the mast in sight..

Anyone else had issues with Topcon signals recently. Had so many excuses from LH Agro that i am getting a little peeved?

 

[Northern farmer]

I have a X30 with a AGI-4. LH Agro have just done an update ( end of warranty) and my RTK went to being almost unusable. So trying a SIM (GPS) to a mast less than 1 mile away. Was ok but only get 3 bars on X30 screen. So we have changed the antenna to a proper GPS. Its a little better but had use the TopNet signal as more reliable. Even with that i only get a max of 4 bars even with the mast in sight..

Anyone else had issues with Topcon signals recently. Had so many excuses from LH Agro that i am getting a little peeved?

Your terminology is confusing. With "SIM (GPS)" do you actually mean GPRS SIM? Also does "a proper GPS antenna" actually mean a proper GPRS antenna for the AGI-4 modem (radio/GPRS modem)?

I doubt a SW update would make a difference on the GPRS modem sensitivity. The signal strength indication might have changed if any.

Did you previously use RTK corrections via a radio modem or via NTRIP (GPRS)? Is the SIM card for the same cellular network as previously? How old is the AGI-4 modem, is it 2G only or 2G/3G?

 

[peachmelba]

Your terminology is confusing. With "SIM (GPS)" do you actually mean GPRS SIM? Also does "a proper GPS antenna" actually mean a proper GPRS antenna for the AGI-4 modem (radio/GPRS modem)?

I doubt a SW update would make a difference on the GPRS modem sensitivity. The signal strength indication might have changed if any.

Did you previously use RTK corrections via a radio modem or via NTRIP (GPRS)? Is the SIM card for the same cellular network as previously? How old is the AGI-4 modem, is it 2G only or 2G/3G?

Northern Farmer. Yes sorry. You are correct.

Was using RTK with a radio base station correction on a neighbors farm less than 1 mile away. Started getting connection issues ( Position Accuracy error) not just under trees but in patches in the middle of the field. So LH Agro came and updated to latest software. Both on the X30 and the AGI-4. Something to do with the Russian satellites being analogue and not digital...

Issue got worse. So I had a spare data SIM (on EE network) as I have a mast less than 1 mile away that I can see. We used the standard laird antenna (470 mhz) with LH Agro NTRIP login details and disabled 3G so it was on 2G only. Got at max 3 bars on screen. Best signal was about -63 dBm and at worse probably about -105 dBm. It was a little better than the radio RTK but still not great. So we then tried using the TopNet service which was a vast improvement, but still got occasional errors with Position Accuracy. So LH Agro ordered a proper Laird GPRS antenna which was installed. The signal improved to at best about -59 dBm but still had odd issue with Position accuracy.

But still only shows at max 4 bars on reception.

The only issue I also have with NTRIP is that if you loose a signal it takes an age to reconnect.

 

[Northern farmer]

Interesting findings peachmelba. Have you followed the RTK correction signal age indicator? If the age is 1 second or so, all is good irrespective of the signal level (radio or cellular).

I have also observed some odd behaviour with our AGCO branded AGI-4 receivers. I've concluded the issue being trees around my home. My base is at the roof of my garage and it had a perfect free sky view when I installed it. Now the trees around the garage start to block satellite visibility to some extent. I thought the issue was a combination of shadowing at the base and another direction at the field.

Interesting if there is an issue with Glonass (not any big surprise from Russia when their priority on investments is very much on different topics these days). Would be nice to get some more details from the Topcon experts that we have on-board at the forum.

Our Valtra screen and receiver were updated some time ago but I could not get the correct software that was referred to at this forum. I reached pretty high managers at the local service organisation but they were not able to provide the SW that I wanted. It had not been released to the official service tools and they either were too dumb or lazy to find it elsewhere. Have no idea if the later SW would have changed Glonass reception.

One more question, when you say it takes ages to reconnect, is that reconnecting the NTRIP correction signal over GPRS? The Topcon GPRS modem control is crazy. I'm sure the Motorola GPRS module works fine but the way AGI-4 controls it is stupid. It always takes a long (a minute at least) time from switch on to get NTRIP running but sometimes it takes forever (5 minutes, 20 minutes, sometimes need to reboot). Our cellular coverage (2G) is perfect and I never have issues once the connection to the NTRIP caster has been established. It still takes a bit too long to recover RTK fix if trees or buildings temporarily block GNSS satellite visibility but this is perhaps less than 10 seconds.

 

[peachmelba]

Northern Farmer.

No I have not really studied the signal age. Wish they had a module or even a developer mode on the X30 so that they can record exactly what is going on with these signals to see what errors are occurring! Little tricky to try and film whats going on as you are driving over a field...

Yes can take an age to get connected over NTRIP, mind you had some issues with RTK over radio as well. Took 2-3 minutes to even register on the screen. I think TopNet service is better as it uses the EE mast near me where as the LH Agro login uses their mast which is some distance (so I have been told). Logging in to the LH Agro mast is quicker but the signal is not as reliable. If you loose NTRIP connection then yes it an take an age to reconnect and sometimes its just looses it completely and just locks out. Reboot isnt required but can take several minutes until it get itself sorted and you can use the guidance again. Luckily it only happens only about once a day.

Reason for posting on AlanT post was I was surprised that I could not get a full signal showing on the screen even with 3G disabled with the new GPRS antenna. My mobile, which is also on EE never drops below 3 bars and is mostly on full 5 bar LTE all the time. Not sure why you would need 3G or even 4G connection (neighbor has a Novotel which is 4G enable!) as 2G has more than enough speed for the required correction info.

I am sure an GPRS antenna with say 3dBi gain would help. I also see Laird do a Dual Band vehicle antennae (GPSD4503P). Would that work best for both RTK Radio and GPRS?

 

[Richard Smyth]

I find the 3G signal on my varioguide setup rarely gets above 3 bars. Sometimes 4 but not often. I do find it works fine with no bars at 30-40 km from the nearest cell tower in very rolling country. Have a tractor coming at end of year which will have Trimble receiver on it. Will be interesting to see how it goes in comparison.

one problem I have here is 3G is being turned off in 2 years time. 4g is very average.
Are there even 4g radios which fit the agi4

 

[Northern farmer]

I find the 3G signal on my varioguide setup rarely gets above 3 bars. Sometimes 4 but not often. I do find it works fine with no bars at 30-40 km from the nearest cell tower in very rolling country. Have a tractor coming at end of year which will have Trimble receiver on it. Will be interesting to see how it goes in comparison.

one problem I have here is 3G is being turned off in 2 years time. 4g is very average.
Are there even 4g radios which fit the agi4

Do I remember right that 2G was discontinued in Australia soon after 3G got coverage? At my place 2G is the only system with true countrywide coverage, 3G is being discontinued. I have 3G activated on our AGI-4 modem but it connects with 2G. 4G has pretty good coverage but I'm not aware of any AGI-4 radio with 4G support. I'm afraid the only option with 4G is to use the AGI-4 external modem port. Commercial products exist but are quite expensive. A $2 bluetooth receiver and a $5 connector plug should be enough to feed NTRIP data from a cellphone (very rural areas would need a proper modem with a roof antenna).

 

[Richard Smyth]

Do I remember right that 2G was discontinued in Australia soon after 3G got coverage? At my place 2G is the only system with true countrywide coverage, 3G is being discontinued. I have 3G activated on our AGI-4 modem but it connects with 2G. 4G has pretty good coverage but I'm not aware of any AGI-4 radio with 4G support. I'm afraid the only option with 4G is to use the AGI-4 external modem port. Commercial products exist but are quite expensive. A $2 bluetooth receiver and a $5 connector plug should be enough to feed NTRIP data from a cellphone (very rural areas would need a proper modem with a roof antenna).

thats correct. I can’t remember when it was switched off but it was a long time ago now.

i can’t get away by sending data from my phone it will have to be a external modem with antennae.

what about Trimble receivers. New tractor is coming with Trimble 382 receiver and hoping it will have a 4g radio. Hopefully the 4g service gets an upgrade prior to needing it. Other option is to switch carriers as Optus don’t have a 3G switch off date yet but are also not as good coverage as telstra. Close though

 

[Ian01]

Use a roaming SIM, signal strength is that of the network provider and has no relevance to proximity to the base

 

[Eddy6170]

I have used mine with the original 450 MHz antennae which worked but not advisable I’ve changed it to a cellular antennae and it’s much better. I’m amazed at where I can get ntrip coverage. It’s reliable up to 100 km from my base station also.

topcon agi4 or Agco ag3000 whatever you want to call it

I know this is a while ago now but what antenna did you get for it please having alot of trouble with our ntrip rtk on our agi4....

 

[Eddy6170]

I have used mine with the original 450 MHz antennae which worked but not advisable I’ve changed it to a cellular antennae and it’s much better. I’m amazed at where I can get ntrip coverage. It’s reliable up to 100 km from my base station also.

topcon agi4 or Agco ag3000 whatever you want to call it

I know this is a while ago now but what antenna did you get for it please having alot of trouble with our ntrip rtk on our agi4....

 

[Northern farmer]

Not asking me but I'd say google for a GSM/UMTS high gain antenna with a TNC connector. Plenty to select from.

Would be good to know what sort of NTRIP problems have you faced? Is it cellular connectivity or something else?

 

[Eddy6170]

Not asking me but I'd say google for a GSM/UMTS high gain antenna with a TNC connector. Plenty to select from.

Would be good to know what sort of NTRIP problems have you faced? Is it cellular connectivity or something else?

I don't really know tbh. I'm starting to think it is the agi4 receivers as we have two of them one with an internal modem roaming sim the other lh agro external modem. Both play up but more do the one with internal modem. I have tried a test signal from rtkf farming as i m getting a little tired of lh agros excuses and service. It seems alot better but still dropping out. It was terrible this morning drilling. Didn't miss a beat this afternoon. Any thoughts would be great.

 

[Richard Smyth]

I know this is a while ago now but what antenna did you get for it please having alot of trouble with our ntrip rtk on our agi4....

It’s a rfi branded antennae. Apparently they are by far the best anyennae manufacturers

 

[Eddy6170]

It’s a rfi branded antennae. Apparently they are by far the best anyennae manufacturers

Where did you get it from please? I can't seem to find one within the 450mhz frequency.

 

[Richard Smyth]

Where did you get it from please? I can't seem to find one within the 450mhz frequency.

Any cb dealer supply them down here in Australia.

RFI 3G/4G High Gain Omnidirectional Antenna CD7195

www.gprsmodems.co.uk

This stockist in the uk seems to have them. I have a cdr7195b