Not capture satellites

Hello, for two days my Alpha + does not capture satellites, I have checked cable, antenna and gps and everything is in perfect condition. When connecting to RTK viewer it looks like this.

What can be the motive?.

Have you tried a factory reset?

I already did that action and nothing

Before Alpha+ didn’t capture satellites, did you make any changes to the device settings? Baudrate? Update rate?

Have you tried to send some commands with GNSS VIEWER?

No, just the usual configuration to operate rtk through ntrip with server and alpha + for android

Just hope someone of Polaris Team can help.
I have an Alpha+ with same conditions but it’s because I did test with some settings and doesn’t recognize satellite anymore.
Maybe with GNSS VIEWER you can find that fix

If there is no voltage at center pin of the Alpha+ SMA connector, then it implies short circuit of RF input in earlier usage had occurred, and below 47nH inductor inside had burnt out.

To get it working, can get a 47nH inductor, solder one end directly to the solder joint of SMA connector signal pin, tap a wire on the other end of the 47nH inductor and connect to PX1122R module pin-23 VCC.

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In my case I do not think it is a short circuit problem, because all the GPS lights are working, whether I change to Bluetooh, USB, etc. In addition, the gps is recognized by the PC or the Cellular. I think rather that he lost satellite agenda. (If my English is faulty it is because I am using a translator, I only speak Spanish)

Burnt of of the inductor has nothing to do with the other good working conditions mentioned. Alpha+ simply provides no 3V supply voltage to power the active antenna.

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Did you have checked with different antenna and RF cable?

No, I have not performed tests with other cables, if with other antennas, and it does not improve.

Most likely what @jackson.lee mentions

If so, it would mean for me to cancel the equipment, as I do not have the technical capacity to change said piece. I’ll see if there is any other solution before leaving the team.

Is there any way to check if the 47nH inductor is actually burned out, for example by measuring the voltage at the cable outlet?

Use a multimeter to check if there is 3V between the SMA connector center pin and outer ground connection.

Could you tell me if the points that I mark with red are the junction points where I would have to solder the 47nH inductor

Whichever of the 2 points easier to solder is OK. Important to have one end of the inductor directly soldered there, to provide high impedance path for RF signal.

Hello Jackson, I would like to know if this failure of the Alpha + has been detected as frequent. I have not been able to repair the gps, and I am afraid that when I buy another this failure will be repeated. For what reason could a cut have been created? The gps had no more than 3 months of use.

Some short at the antenna side burning out the Alpha+ internal active antenna bias inductor.

Very few customers have such issue. One customer with poorly made long RF cable connecting between Alpha+ and survey antenna had several occurrence of such issue over time previously. After they changed to better quality RF cable, and the issue was gone.

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Good night, did you manage to do the alpha + repair? I have the same problem