Emlid NTRIP Caster: Free and Easy Way to Pass RTK Corrections

Hi Jan-Olov,

The mount point should be the same as the one you used previously. You can check it on the caster page. Please ensure that both your units are connected to the Internet.

4 posts were split to a new topic: U-blox F9P can’t be connected to Internet

Is there any possibility to add some “translation” option of MSM4 messages to legacy RTCM3.0 messages? This could be done by creating another user mountpoint with RTCM3 suffix.
Some COORS offer multiple mountpoints e.g. RTK_MSM4, RTK_RTCM3.0 or VRS_RCTM3.2 etc.
This could be really helpful for users working with older receivers that doesn’t support MSM4 messages.
For more information see here.

1 Like

This has been asked in other threads. In particular message 1008 for Trimble receivers. It is on their list of things to do but no eta on completion.

I am playing with arduino to add the 1008 currently to the output of the M2. I will be using 3DR radios to transmit/receive once completed. If it works, it will be a cost affective manner to do so.

Hi @vgo195,

Thanks for the request and info! We’ll check how we can implement it in the future.

As @jp-drain-sol mentioned, we’re also looking into the possibility to support legacy messages output. Currently, I can’t share any specific dates with you.

A post was split to a new topic: Instrucciones de creación de perfiles ntrip con reach view 3


This is great news for all drone mappers out there. Thanks a lot Emlid !

I have a question :
Do you need to have both base and rover connected to the internet to work with Emlid NTRIP Caster ? Or is it possible to juste have the base connected to the internet broadcasting corrections to the rover (like in a regular RTK Set up) ?

This question is particularly relevant in the case of the M+/M2 unit mounted on a regular Phantom 4 pro. It is sometimes difficult to maintain a stable and continuous wifi connexion to the aircraft during the whole flight, but you can have a radio connexion via the lora antenna.

Thanks again Emlid.


You need internet connectivity for the rover to receive data from the caster.
On a UAV, it could be done with a 3g-4g-5g modem connected to the m+/m2.

1 Like

Thank you for the answer. So you cannot transmit corrections via the radio antenna when using Emlid Caster corrections on your base, correct ?

You can, but then it is not the casted correction, but correction of the local base.

got it ! thanks a lot

Any plans of permitting all users of the caster system a way to tie each mount point together into a large VRS or RTN?

How would you precision in such a setup, where there is no central control?

1 Like

A large VRS or RTN requires a server with high bandwidth depending on how many users there are, and the VRS software. I doubt without a fee it would be doable. If you have a fee, you must also have support personnel to assist with problems. THAT IS A FULL TIME JOB! Have you noticed how many questions there have been since Emlid introduced their caster.

1 Like

Hey Seth,

Thanks for your request! We’ll note it. However, currently, we don’t have such plans.

Hi everybody, greetings from Chile.

I have a question about the caster.

Already bought two emlid RS2 receivers and I’m planning on using one as a base and the other as rover. Already connected the two receivers to the emlid ntrip caster, as base and rover, and the two appears “Online”. Now the question is about my baseline. On my “base” I have a baseline over 7000 km and on my “rover” I have a baseline about 10m (the distance between my base and rover, so that’s ok).

My doubt now is for the first baseline, between my base and the caster itself. It’s fine to have such a giant baseline (over 7000 km)? or should I need to buy an account on a ntrip caster near my area or a ntrip service specific for my country? … I mean, I saw several videos and your tutorials and specifications but in all they say that the baseline should be <100km for RS2 (Placing the base)

Need more info about this please, the corrections that I’m sending to my rover are really correct with a baseline over 7000km?

Thanks in advance for the reply.




7000 km is way too much, for multi frequency RTK 60 km is the limit.


Hi Luis,

From what you described your rover seems to be connected to your base properly and you are getting a correct baseline.

There is no such things as a baseline between your base and caster, caster does not produce any corrections, it just relays what your base is sending to your rover.

What is likely happening is that you have configured Correction Input on your base and you are receiving some correction there and this is why you see this huge baseline. It does not actually affect the operation of your base, but simply disabling Correction Input on your base should make everything look right.

If this doesn’t help, please post screenshots of how you Correction Input and Base Mode are configured on your base.


Hey Igor, thank you very much for the reply. I realized that you are right, by mistake I had the input correction in the base activated. When disabling it, the baseline of more than 7000km disappeared.

Have a nice day!


I see a case for this but it would have to be a select group of Mount Point Casters, this would be to for QA & QC and maintenance/trouble shooting of the positioning data being cast and GNSS system setup by the group of users(volunteers).