FYI - GPS

[VK3KYY]

The JumpStar GPS is the old module.

I doubt TYT are manufacturing the UV380 / RT-3S with the GPS module in it any more.

However there will be a lot of radios in warehouses and at distributers which are effectively old stock.

Moving the antenna to face upwards helps, but is not an easy job

[SA0BUX]

The JumpStar GPS is the old module.

I doubt TYT are manufacturing the UV380 / RT-3S with the GPS module in it any more.

However there will be a lot of radios in warehouses and at distributers which are effectively old stock.

Moving the antenna to face upwards helps, but is not an easy job

I took a peek on https://retevis.com and it seems that RT3S with GPS is produced as it is out of stock and will come back in December.

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[EU1AEQ]

I have 2 radio stations: RT3S with GPS and 380UV without GPS. In RT3S I replaced the antenna, the amplifier, replaced the module with ATGM336H-5N-71. There are no special changes in the speed of satellite detection. It works very slowly. Finds up to about 9 satellites. In 380UV I put an external module with an active antenna. Satellites are detected in a minute. Shows more than 20 satellites. In both cases, the antenna is on the side. Something is wrong in the circuit diagram of models with GPS.

[ca3imf]

Hello guys

Im having a big issue with the gps, yesterday for some reason the gps stopped working without receive a signal in the full day, I flashed the firmware again to the lastest one and now I cant activate de gps in a RT3S. I dont know whats going on, the top knob is like blocked in that particular option.

[VK3KYY]

Hello guys

Im having a big issue with the gps, yesterday for some reason the gps stopped working without receive a signal in the full day, I flashed the firmware again to the lastest one and now I cant activate de gps in a RT3S. I dont know whats going on, the top knob is like blocked in that particular option.

Sounds like the GPS module is not working.

The only way to confirm this would be to open the radio and connect to the Serial / RS232 data signal from the module, to confirm whether it was outputting any data

[KB8YKF]

I have two Retevis RT3S units now. One was purchased November 20th from Amazon in USA and has a manufacture date of July 2023. The manufacture date is on a security (warranty) sticker covering a screw in the battery compartment.

The other was purchased November 28th directly from retevis.com website and has a manufacture date of October 2023.

Neither would do a cold start inside from 1st floor of a two story house with aluminum siding. So I brought them outside and they each saw a satellite immediately after turning them on. Within a minute they each had a few satellites and knew their location. In the photo below, the Oct 2023 unit had one more satellite and a little better signal strength.

But I brought them indoors and the July model immediately lost its location, but the October model continued acquiring more satellites! It seems to have a more sensitive GPS receiver.

I'd take it apart but still on the fence about destroying warranty stickers!

[OE1MWW]

Neither would do a cold start inside from 1st floor of a two story house with aluminum siding.

It's a amzing that people from the US very often refer about GPS 'indors' and 'outdoors'. Indoors, if you live in a wooden house,
maybe, GPS is possible. But you can't cheat physics. Shielded is shielded. Most buildings in Europe, if not all of them, are made
of concrete walls with steel arming. Indoor GPS reception is therefore an illusion, common knowledge..

Btw., this has been reported here a while ago - the 'newer' versions of RT-3S (so as mine, one of 3 RT-3S) has a better (more sensitive)
GPS receiver and an another CPU.

Wolfgang
OE1MWW

[KB8YKF]

Btw., this has been reported here a while ago - the 'newer' versions of RT-3S (so as mine, one of 3 RT-3S) has a better (more sensitive)
GPS receiver and an another CPU.

This was the point of my post, I thought a radio I bought exactly 30 days ago made as recently as July would be 'newer' but it was not. Both have the clone TYT CPU. I read those same reports and thought I'd get an updated model. It seems whatever change is VERY recent.

I would suggest that if someone wants a version with updated GPS receiver the best chance is to go right to the manufacturer until old stock in warehouses is turned over, and there is no way of knowing when that will be.

[KB8YKF]

One last test, this time I did a cold start from indoors - didn't venture outside. I assumed neither unit could acquire a signal inside, why my first test I briefly took them both outside for initial acquisition. But it turns out the newer unit CAN get a signal from an indoor cold start, as long as I'm not impatient and give it some time. This photo was taken 15 minutes after turning on both units. So it seems the unit I ordered directly from Retevis versus Amazon clearly has a better GPS receiver setup. It got up to 11 satellites after I took the photo.

[VK3KYY]

It should be noted that atmospheric conditions and also the position of the GPS satellites can effect acquisition times

E.g. the GPS in my car has its antenna at the front of the dashboard, and some days when it's raining or thick cloud, I have to drive for a few minutes before the GPS gets a 3D fix