Portable RTK Receiver/Base for $799

[Pheasant Surprise]

Just seen some banner ads on here for Emlid Reach RS portable receiver.

...yeah, yeh I know its still only single L1 frequency, and bit limited spec, but look out boys and girls that price point is looking attractive....

#RTK_for_the_masses

 

[Northern farmer]

Add AgOpenGPS software for that and it makes a total of $799.

I guess the lack of L2 (and others) makes no big difference if you are operating close to your own base? Does it still affect time to RTK fix?

 

[Pheasant Surprise]

Have you tried AgOpenGPS yet? Keep meaning to put it on a tablet and give it a go.

Not sure about what time to fix would be real world with one of these - or absolute accuracy - won't obviously be as good as L1/L2 but getting L2 on a box appears to at least double the asking price.

 

[Robt]

Have you not bought one yet? This is getting as long as forage traders car buying

 

[Pheasant Surprise]

Have you not bought one yet? This is getting as long as forage traders car buying

Haha. No I'm all good - bless FT. I wouldn't be able to sum up the patience for that.

 

[Clive]

Just seen some banner ads on here for Emlid Reach RS portable receiver.

...yeah, yeh I know its still only single L1 frequency, and bit limited spec, but look out boys and girls that price point is looking attractive....

#RTK_for_the_masses

that ad has been one of the most clicked on TFF ever - clearly has caught the attention of a few ...................... including me as it does seem incredible value ???

 

[Pheasant Surprise]

that ad has been one of the most clicked on TFF ever - clearly has caught the attention of a few ...................... including me as it does seem incredible value ???

Yes it's not really up there with the best portable receivers from Trimble or Topcon, but it is roughly 10% of their asking price, so yeah not surprised it's getting plenty of click throughs.

 

[Clive]

Yes it's not really up there with the best portable receivers from Trimble or Topcon, but it is roughly 10% of their asking price, so yeah not surprised it's getting plenty of click throughs.

surely RTK is RTK ? only catch I could see is you would need x2 receivers to make it work to that level of accuracy but even x2 is way cheaper than existing solutions ?

 

[Pheasant Surprise]

surely RTK is RTK ? only catch I could see is you would need x2 receivers to make it work to that level of accuracy but even x2 is way cheaper than existing solutions ?

That's a really good question and I guess the biggest difference you would see would be what is level of accuracy degradation when you go past a certain distance (whatever that may be) from your base, and how messed up is my position going to be in cloudy or unfavourable weather (ionospheric affects of the signal) which L1/L2 receivers can resolve but L1 only receivers can't.

It's a cost / benefit tradeoff.

 

[Northern farmer]

surely RTK is RTK ? only catch I could see is you would need x2 receivers to make it work to that level of accuracy but even x2 is way cheaper than existing solutions ?

Do you mean x2 because of one receiver for the RTK base and the other one for the tractor while some other options may come close "with one receiver only"? Here it would be x2 in the worst case. If the farm had several tractors equipped, a single base would still be sufficient.

It could be more than x2 if the max range makes a difference (for a farm that has fields very far away, I guess further than 10 or 20 km away from the base).

 

[Clive]

Do you mean x2 because of one receiver for the RTK base and the other one for the tractor while some other options may come close "with one receiver only"? Here it would be x2 in the worst case. If the farm had several tractors equipped, a single base would still be sufficient.

It could be more than x2 if the max range makes a difference (for a farm that has fields very far away, I guess further than 10 or 20 km away from the base).

Yes my understanding would be you would need a base and then another RTK receiver / radio on each tractor

thats the same for all brands though


its seems like value - would love to hear from a user (if there are any in the UK yet ?) They are HK based but seem genuine (i.e. they paid their bill for the ads quickly)

 

[Robert Ramsay]

I am afraid that having 2 L1 receivers will not duplicate the accuracy of an L1/L2 receiver. The L2 signal is a substantially different and I believe higher frequency signal and it is this one that supplies the accuracy.

 

[ManuelMorales]

I am afraid that having 2 L1 receivers will not duplicate the accuracy of an L1/L2 receiver. The L2 signal is a substantially different and I believe higher frequency signal and it is this one that supplies the accuracy.

There is no difference in accuracy between l1 and l1/l2.

l1 limitations are:
1. Time to get fix (few minutes vs few seconds)
2. Baseline (10 km vs 100 km)

 

[Pheasant Surprise]

There is no difference in accuracy between l1 and l1/l2.

l1 limitations are:
1. Time to get fix (few minutes vs few seconds)
2. Baseline (10 km vs 100 km)

Unless your a surveyor in the outback long baselines (100km) are academic. What is far more important is atmospheric effects (tropospheric delay) which degrades the level of precision. L1/L2 receivers can compensate for this but L1 only receivers cannot.

I've only ever used L1/L2 (various makes) of receiver so I can't categorically say how much worse an L1 only receiver would be in the real world.

Have you actually used an L1 only receiver in Ag and how did you get on?

 

[ManuelMorales]

Unless your a surveyor in the outback long baselines (100km) are academic. What is far more important is atmospheric effects (tropospheric delay) which degrades the level of precision. L1/L2 receivers can compensate for this but L1 only receivers cannot.

I've only ever used L1/L2 (various makes) of receiver so I can't categorically say how much worse an L1 only receiver would be in the real world.

Have you actually used an L1 only receiver in Ag and how did you get on?

I am in agricultural drone mapping with small Emlid units (recently got hands on AgOpenGPS) but the performance should be the same for the big. So within the baseline of 10km atmospheric effects won't affect the accuracy.

https://emlid.com/reach-rs-field-tests/
https://emlid.com/reach-rs-for-precision-farming-machineryguide/

 

[Badshot]

I asked if it would work with the main ag GPS screens. . I got this reply,


Thank you for your interest to Reach RS!

Reach RS may output the position in different formats including popular in the industry NMEA 0183. You can output the position using Bluetooth, TCP or RS232 port of Reach RS. Please check out the docs entry for more information.

I can't say for all the screens and devices but it seems it should work with ones supporting position input via BT or RS232.

Please let me know if you have further questions!


Best Regards,
Dmitriy Ershov
Emlid Ltd

Anyone care to put that in English?

 

[Pheasant Surprise]

I am in agricultural drone mapping with small Emlid units (recently got hands on AgOpenGPS) but the performance should be the same for the big. So within the baseline of 10km atmospheric effects won't affect the accuracy.

https://emlid.com/reach-rs-field-tests/
https://emlid.com/reach-rs-for-precision-farming-machineryguide/

Have you compared repeatability performance with an L1/L2 receiver? I fear there will be a difference, how big is debatable.

If you don't need proper year in year out RTK repeatability then you might be fine - depends on your expectations.

 

[Pheasant Surprise]

Anyone care to put that in English?

They use standard NMEA 0183 connection using serial port (or bluetooth, etc etc) to your device. Like any box that needs GPS data input/output does now.

 

[Badshot]

They use standard NMEA 0183 connection using serial port (or bluetooth, etc etc) to your device. Like any box that needs GPS data input/output does now.

So it should work with the main brands then.
The rtk receiver in my trimble (cnh) 750 screen would pick it up?

 

[Pheasant Surprise]

So it should work with the main brands then.
The rtk receiver in my trimble (cnh) 750 screen would pick it up?

Apologies I misunderstood. I thought you wanted to connect the Emlid receiver to a control box needing a GPs position/speed input. Can't really see what directly connecting both the Emlid and CFX receivers together on the tractor would achieve

What sort of thing did you have in mind?

You could potentially set one of these up an Emlid as a portable base and have it send RTCM type corrections to your CFX (although your CFX would need to be unlocked for RTK) - it should in theory work but you'd need to be a guinea pig. You'd also need to get some compatible radios at both ends. The Emlid has a built in radio, but looks like it's aimed at the US market and doesn't use our usual 450-470 MHz spectrum.

The other way would be to get two Emlid receivers; set one up as a base again and the other set up in the tractor as the rover, independant of any other receiver.