GPS issues on GTA02v4

[Daniel Willmann]

Hello,

On Tue, 4 Mar 2008 09:13:25 +0800
<SHAWN_LIN at fic.com.tw> wrote:

> I am the hardware engineer dedicate to RF parts. After reading your
> statement about this issue, this issue may be caused by bad
> connection of internal GSP antenna. Some tests should be performed on
> your Neo. I will also send you two antennas. One is internal and the
> other one is external. 

thanks for offering that, but no need. I already have an external
antenna here and I have a couple Neos from which I can take internal
antennas.

> 1. Replace the new one on your Neo and check signal quality (In
> open-sky, the TTFF is less than 50s)

> If the result follows my expectation, the reason for this issue may
> be repeat de-assembling to damage the RF cable of the internal GPS
> antenna. 

I already tested another (known good) internal GPS antenna which didn't
work either. My multimeter says the cable on both antennas are okay.

> If not, I think you can do the next test 
> 
> 2. Plug the external antenna in our Neo and check the signal quality 
> 
> If the GPS is normal, I think the RF switch circuit (ESD sensitive)
> is complete break-down. 

Yeah, did that and it got a fix in ~40s, so the GPS chip itself is
working.

> I will send you these two antenna as soon as possible. If any
> question, let’s discuss together. 

If you have an idea what I can do to test the RF switch circuit let me
know. I do have a soldering station and know how to use it. :-)

Regards,
Daniel Willmann
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