# can I use a passive antenna with the SparkFun GPS-RTK2 Board - ZED-F9P (Qwiic) ? **URL:** \ **Category:** Development Boards\ **Created:** [November 5, 2019, 11:40am UTC](https://community.sparkfun.com/t/can-i-use-a-passive-antenna-with-the-sparkfun-gps-rtk2-board-zed-f9p-qwiic/38158 "2019-11-05T11:40:16Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![foxhound](https://avatars.discourse-cdn.com/v4/letter/f/ea5d25/32.png) [@foxhound](https://community.sparkfun.com/u/foxhound)\ **Post date:** [November 5, 2019, 11:40am UTC](https://community.sparkfun.com/t/can-i-use-a-passive-antenna-with-the-sparkfun-gps-rtk2-board-zed-f9p-qwiic/38158/1 "2019-11-05T11:40:16Z")
Hello I want to make a permanent base station in my roof and I want to use my old GNSS reciever antenna Ashtec promark 100 which I believe is a passive antenna, is it possoble to use it with the SparkFun GPS-RTK2 Board - ZED-F9P (Qwiic)? ---
**Author:** ![El\_Duderino](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/el_duderino/32/6367_2.png) [@El\_Duderino](https://community.sparkfun.com/u/El_Duderino)\ **Post date:** [November 5, 2019, 6:36pm UTC](https://community.sparkfun.com/t/can-i-use-a-passive-antenna-with-the-sparkfun-gps-rtk2-board-zed-f9p-qwiic/38158/2 "2019-11-05T18:36:03Z")
Hi foxhound, Unfortunately, it looks like that, or any passive antenna, will not work with the ZED-F9P. Per the [[ZED-F9P Integration Manual](https://cdn.sparkfun.com/assets/learn_tutorials/8/5/6/ZED-F9P_Integration_Manual.pdf), an active antenna is required. Here is the full quote from the Antenna section (8.3): > u-blox highlights that the use of an active antenna is a pre-requisite for using the ZED-F9P. > > If an active antenna needs to be implemented in an application case, it is recommended > > that an OEM active antenna module is used that meets our specification. To implement the > > required RF circuitry and source the required components to meet group delay specification > > is not a simple process compared to previous L1 only implementation." The [[ZED-F9P Product Page](https://www.sparkfun.com/products/15136) has a few antennas in the “Hookup Accessories” carousel that we have tested that work with the ZED-F9P and this [[white paper](https://cdn.sparkfun.com/assets/learn_tutorials/8/1/4/AntennasForRTK_WhitePaper__UBX-16010559_.pdf) from u-blox goes over using low-cost antennas to get centimeter-level accuracy with them. Lastly, I would recommend reading through our [[Hookup Guide](https://learn.sparkfun.com/tutorials/gps-rtk2-hookup-guide) for the ZED-F9P GPS-RTK2 as that will go over getting started using the board.]([GPS-RTK2 Hookup Guide - SparkFun Learn](https://learn.sparkfun.com/tutorials/gps-rtk2-hookup-guide))]([https://cdn.sparkfun.com/assets/learn\_tutorials/8/1/4/AntennasForRTK\_WhitePaper\_\_UBX-16010559\_.pdf](https://cdn.sparkfun.com/assets/learn_tutorials/8/1/4/AntennasForRTK_WhitePaper__UBX-16010559_.pdf))]([SparkFun GPS-RTK2 Board - ZED-F9P (Qwiic) - GPS-15136 - SparkFun Electronics](https://www.sparkfun.com/products/15136))]([https://cdn.sparkfun.com/assets/learn\_tutorials/8/5/6/ZED-F9P\_Integration\_Manual.pdf](https://cdn.sparkfun.com/assets/learn_tutorials/8/5/6/ZED-F9P_Integration_Manual.pdf)) ---
**Author:** ![foxhound](https://avatars.discourse-cdn.com/v4/letter/f/ea5d25/32.png) [@foxhound](https://community.sparkfun.com/u/foxhound)\ **Post date:** [November 6, 2019, 7:32am UTC](https://community.sparkfun.com/t/can-i-use-a-passive-antenna-with-the-sparkfun-gps-rtk2-board-zed-f9p-qwiic/38158/3 "2019-11-06T07:32:00Z")
Thank you for the reply , SO i have to buy OEM active antenna module , is the center of this antenna precisely specified so I can centred it in a specific known point? ---
**Author:** ![El\_Duderino](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/el_duderino/32/6367_2.png) [@El\_Duderino](https://community.sparkfun.com/u/El_Duderino)\ **Post date:** [November 6, 2019, 7:41pm UTC](https://community.sparkfun.com/t/can-i-use-a-passive-antenna-with-the-sparkfun-gps-rtk2-board-zed-f9p-qwiic/38158/4 "2019-11-06T19:41:15Z")
These three antennas will work just fine with the ZED-F9P: - - [[GNSS Multi-Band Magnetic Mount Antenna - 5m](https://www.sparkfun.com/products/15192) - [[Datasheet](https://cdn.sparkfun.com/assets/1/8/f/f/0/ANN-MB\_DataSheet\_\_UBX-18049862\_.pdf) [/list]- - [[GPS/GNSS Magnetic Mount Antenna - 3m](https://www.sparkfun.com/products/14986) - - [[GPS/GNSS Embedded Antenna - 1m](https://www.sparkfun.com/products/14987) [/list] We do not have datasheets for the 1 and 3m GPS/GNSS Antennas but we do have one for the u-blox antenna I have linked above. The datasheet does not mention a phase center but it does have the radiation pattern listed. With a grounding plate and an RTK lock, you should be able to get centimeter accuracy for your base. If you need higher accuracy, you may want to look for a different antenna that has the phase center listed.]([GPS/GNSS Embedded Antenna - 1m (SMA) - GPS-14987 - SparkFun Electronics](https://www.sparkfun.com/products/14987))]([GPS/GNSS Magnetic Mount Antenna - 3m (SMA) - GPS-14986 - SparkFun Electronics](https://www.sparkfun.com/products/14986))]([https://cdn.sparkfun.com/assets/1/8/f/f/0/ANN-MB\_DataSheet\_\_UBX-18049862\_.pdf](https://cdn.sparkfun.com/assets/1/8/f/f/0/ANN-MB_DataSheet__UBX-18049862_.pdf))]([GNSS L1/L2 Multi-Band Magnetic Mount Antenna - 5m (SMA) - GPS-15192 - SparkFun Electronics](https://www.sparkfun.com/products/15192)) ---
**Author:** ![foxhound](https://avatars.discourse-cdn.com/v4/letter/f/ea5d25/32.png) [@foxhound](https://community.sparkfun.com/u/foxhound)\ **Post date:** [November 6, 2019, 9:18pm UTC](https://community.sparkfun.com/t/can-i-use-a-passive-antenna-with-the-sparkfun-gps-rtk2-board-zed-f9p-qwiic/38158/5 "2019-11-06T21:18:08Z")
ok, thank you!