FYI - GPS

[SP9TA]

Hello all. I don't know how you guys accomplished this, but whatever I try, this GPS barely works at my place.
Factory, in the flat by the window, facing the GPS antenna towards the sky 0 satellites.
As above, but without the RT3s enclosure, so that the antenna is exposed: 2-3 satellites, no fix even after half an hour. On an outside window sill sometimes manages to catch a fix on 3 satellites but rarely. In an enclosure never .
Outside with exposed sky fix minimum 2 minutes 30 seconds and sometimes 10 minutes still no fix. Without the enclosure it works significantly better, then the first satellite appears very quickly, but it is very far from what you show on screens or videos. The maximum I have seen outside is 5 satellites and here you show screenshots with 16 satellites.
I bought these antennas on Amazon, but from the link https://www.amazon.pl/dp/B0BSFDHKFY, because the one previously given was not available, and I did the following tests:
- I replaced the antenna itself, without its pcb, being careful that the new one makes good ground contact on the Retevis PCB. - It works just as poorly as the factory one
- I replaced the amplifier with an AL5 - no improvement, same thing
Seeing no change, I bypassed the circuitry on the RT3s board and connected the second antenna from the set without changing it, as an active antenna, directly under the GPS module (pin 11 RF_IN via a capacitor what is to that pin on the RT3s PCB), and VCC via a 47nH choke from pin 14 (VCC_RF) - also no change, same thing.
Perhaps these GPS modules differ in sensitivity? My module is the Jumpstar JS-H210 F67. What else could I do?

[VK3KYY]

The GPS in my RT3S is also very insensitive

I didn't try replacing the antenna yet.

But I did also buy some very tiny GPS modules with separate antennas, which I am waiting to arrive.

Possibly you would need to install a replacement GPS

[ik2tif]

Good morning everyone,

I installed the mod on my Retevis RT3S (no GPS) as instructed by CU7AAZ and I thank him.
Everything works very well, acquires satellites very quickly.
While assembling the board, I broke the inductance as indicated by the red arrow, but I don't know the value.
The radio still works, and I don't know what this missing component is for.
Can someone help me ? is there a electric diagram of the radio?
I take this opportunity to thank all the authors of OpenMDUV380 for this amazing firmware.
Thank you

Fabio IK2TIF

[CU7AAZ]

Good morning everyone,

I installed the mod on my Retevis RT3S (no GPS) as instructed by CU7AAZ and I thank him.
Everything works very well, acquires satellites very quickly.
While assembling the board, I broke the inductance as indicated by the red arrow, but I don't know the value.
The radio still works, and I don't know what this missing component is for.
Can someone help me ? is there a electric diagram of the radio?
I take this opportunity to thank all the authors of OpenMDUV380 for this amazing firmware.
Thank you

Fabio IK2TIF

Hi,

Value inductor is 10nH

https://pt.aliexpress.com/item/10050030 ... pt=glo2bra

the same happened to me

best 73s

Cu7AAZ

[ik2tif]

Many thanks for the information my friend.

Have a nice day.

73's

Fabio IK2TIF

[CU7AAZ]

No problem my Friend.
It's a pleasure to help with something.
Feel free to ask if you have any questions about the mod.
By the way, which mod did you do?
Soon I will publish some more information about installing the GPS module. I forgot some details, and I will also add information about the backup battery that comes with the module.
Best 73s
CU7AAZ

[ik2tif]

Hello,

I made the mods as you indicated in GPS2 file. (with aliexpress gps module and amplified antenna)

I would like to know what the inductance I broke is for, what is its purpose.


have a nice weekend

IK2TIF

[EU1AEQ]

What is the feature of mounting the board? How to avoid inductance breakdown? Ordered a GPS kit. I will try to install it.

[CU7AAZ]

The inductor broke due to the attempt to leave the module on the right side.
Conclusion, the GPS module must be on the left side. As low as possible, remove as much plastic as you can.

GPS mod 2
https://drive.google.com/file/d/1VrMJm0 ... sp=sharing

73s
CU7AAZ

[EU1AEQ]

GPS mod 2
https://drive.google.com/file/d/1VrMJm0 ... sp=sharing

CU7AAZ

The link is corrupted. Are there any changes in the mod 2 file?