FT 991A + Internal GPS receiver 

Thank You! I ordered the same level converter board you used and eBay item # 132475473691 shows the board connections. I also ordered a GPS module GY-NEO-6MV2. I will not open the case of the FT-991A and I'll get 5VDC from a LM7805. I plan on using the radio for POTA. Thanks again! 73 de WA2SST

Thank you, There are many ways to install a receiver, I just found the best position for me.

Hello, GPS receiver connected to pin 11 (input TTL) Transceiver to pin 14 (output RS232) More info in the datasheet.

@@UT4UFA Thank You! I ordered the same level converter board you used and eBay item # 132475473691 shows the board connections. I also ordered a GPS module GY-NEO-6MV2. I will not open the case of the FT-991A and I'll get 5VDC from a LM7805. I plan on using the radio for POTA. Thanks again! 73 de WA2SST

The module is outdated and is pretty hard to find. I most likely suggest finding a more modern version of this.

@@UT4UFA ok thank you. Any suggestions where to look for a module that will work? I just looking for the gps to work on my 991a

@@charlesriley9426 Well, there are many good GPS modules present on a market. You need one with an NMEA data format, TTL or RS232 port, and a data rate of 4800-38400bps. Try the NEO-6M GPS module, and do not forget about TTL to RS232 converter.

Hello, Yes, there's a bit of confusion. I know a several users also attempted to connect a GPS via pin #3 without success. Please carefully read the original Operating Manual (2111A-KS-1), specifically on page 19, in the top right corner: "[GPS/CAT] ② SERIAL OUT/RXD (GPS DATA IN)." So, what does this mean? When using CAT, pin #2 serves as data output. However, if you change the setting in the transceiver (field 028) to utilize an external GPS, pin #2 undergoes a change in its properties, now functioning as a data input. The Yaesu FT-991A is a powerful transceiver with numerous features and flexible settings. Delve into its functionality as thoroughly as possible. By adeptly applying various settings, you can achieve excellent results. 73!

@@UT4UFA TNX for you explenation sorry for my bad english , i have a GY-NEO6MV2 gps module from alie can you thel me witch connextion i must wire to the yaesu ft 991A (i think TX from the gps To pin 2 yaesu) or is it RX To the yaesu the gps is blinking blue everry second , must i reset the tranceiver ?? or must i use a ttl converter ? have a nice day and evening PA0EHJ 73"s

To start, download the datasheet for your GPS receiver. Identify the port type: RS232 or TTL/CMOS to determine if a level converter is necessary. Additionally, take into account the settings on both the transceiver and the GPS receiver. It will take some time , but only then you can determ compatibility.@@janvanderlinde3039

@@UT4UFA Tnx for you reaction pls can you tell me which ( RX or TX ) i must connect from the GPS module TO the 991A pin 2 ? RX OR TX ??? keep strong we think of u and try to help

All details regarding the connecting and assigned RX/TX ports and the remapping of data ports should be available in the datasheet. Any actions you take are at your own risk.@@janvanderlinde3039