PilotAware

British Forum => Technical Support => Topic started by: smunch on March 03, 2019, 03:25:13 pm

Title: GPS Battery?
Post by: smunch on March 03, 2019, 03:25:13 pm

Hello,

I have one of the original Pilot Aware systems with the GPS/Glonass oval shaped dongle.  Recently its taking many minutes to get a fix if the system has not been used for several days.  From reading this forum it sounds like the battery in the dongle is starting to fail. 

Is it possible to replace the battery?

thanks
Steve

Title: Re: GPS Battery?
Post by: Vic on March 03, 2019, 05:02:55 pm

Hi Steve  ..for what it costs, I'd say it isn't really worth it
https://www.ebay.co.uk/itm/VK-172-USB-GPS-Receiver-Ublox-7-Win-7-8-10-Linux-Ras-Pi/192372624724

Here's mine out of interest. (the case gently prises open)

(http://i64.tinypic.com/sq72tw.jpg)


The battery has tags spot welded on which are then soldered down to the PCB.  The cell measures around 4.5 x 1.5mm.

Mine measures a voltage of 1.92 volts suggesting that it too is a 'just about to die' lithium cell!  The PCB has a manufacture date of week 22 in 2015 making that 3 years old.

Title: Re: GPS Battery?
Post by: Vic on March 03, 2019, 06:20:18 pm

Delving deeper, and measuring mine at 3.1v when powered up,  the battery is rechargeable, likely one of these..

https://www.sii.co.jp/en/me/datasheets/ms-rechargeable/ms414ge/

Looking at the spec sheet, the charging current is tiny (<1% charge gain per hour!) and will take approx 200 hours to charge fully.

Perhaps with the relative infrequent 'power on time' these dongles get in our pilotawares, they are simply discharging over a couple of years and never charging up enough when powered for a flight duration.

I'm going to leave mine in a USB port of my PC (it has a  mode where they stay powered when shutdown) for a few days. Suggest you try the same!

Title: Re: GPS Battery?
Post by: smunch on March 03, 2019, 09:48:12 pm

Hi

Thanks,  great information and advice. 
Much appreciated.
Cheers
Steve.

Title: Re: GPS Battery?
Post by: bnmont on March 07, 2019, 08:05:04 pm

I have also suspected the internal battery failing.
Opened dongle up, voltage at Battery 0.08v. On charge 3 days it’s now reading 3V.
Hope satelite acquisition times improve.