Thread: GPS receiver with external antenna?

Laidback:

I think there are levels of DR and that all receivers have som kind of DR.

This unit (Trimble Lassen DR+GPS) require speed, direction (forward/revers) and ignition input and has internal gyro.

For BMW's there might be a difference also from Mk I-II that has this separate receiver and the later NAV computers with integrated receiver so that they have more advanced DR. This BMW receiver (65908385141) lacks that input.

Well, I'm just guessing really.

But it would be great to be able to keep some kind of position even in bigger thunnel systems with lots of exits like "Stockholm Sodra lanken" :-)

---

One more guess about the RXD, RXDN, TXD and TXDN. Soem Trimble devices talk NMEA as well as TSIP (Trimble Standard Interface Protocol)

Mark I and II of BMW does not have DR (in the GPS receiver). If there is one its in the NAV computer which does not help me.

I agree that its not worth while without DR, now that I know that it exist :-) If it hadn't have these technical problems it would have been a cheap way of getting GPS receiver with connection for external antenna.

At the moment I am trying to find a distributor for "Trimble Lassen DR+GPS" in Sweden and hopefully its not to expensive.

Thanks for the thread pointer! I will read it through carefully.

Oj

Heavy reading. I'm exhaused. So I want DR, and what it destills down to as far as I understand is the following:

There is a GPS receiver board RCB-4H at €105

And a possibly newer u-blox unit EVK-5H at €150

There is also a complete kit AEK-4R with gyro at €500 (!!!) which I suspect is built around the RCB-4H?

There is also the Lassen DR+GPS eval kit that I have not yet found a source and price for.

Unfortunately I cannot be able to find the Murata (or any other for that matter) gyro.
Q1-> Is it old?

----

There seems to be a number of pcb's made in the comunity to glue the kit together, but I have not seen one offering to sell one!

And apart from that in this new world that opens up to me there are active and passive antennas. I guess it is just a matter of preamp or not and both should work, only active is better?

----

As this obviously been done before, please spoon feed me:
Q2-> What should I buy from whom? (I do not mind building some glue electronics)

Q3-> Is the best option to get a good grip in the wallet and purchase the AEK-4R?

BR, B-O

Agree!

But then I need a gyro. What do you think of this one?

Epson

This is what I use. No DR but it works great. It doesn't show it in the pictures (or talk about it at all in that particular auction), but it does have a tiny gold MMCX connector on the side of it. I have it mounted in my center console and connected to a 30db gain external antenna. When I travel, I can easily disconnect the antenna, pull the SUG-226 off the hub in my center-console, and then use it with my laptop. I love that thing... super tiny/prtoable, super fast Sirf3 acquisition, and a great internal antenna + external antenna connector.

This also looks interesting.

Thanks for links newb77!

External antenna is requirement so the one you use is not an option for me.

Second one would defenitely been what I would have gone for 3 days ago, but now I've really got interested in the consept of dead reconing.

Laidback: Both kits have got gyro's, but the AEK-4R contains rev 4 of the u-blox and is $500 and the second (Lassen DR+GPS) I cannot source.

So I will probably buy the Epson gyro and the rev 5 u-blox unless any of you see any incompatibility.

I will design hw around it and publish (sell maybe) if successful.

Help appreciated.