Saturday, June 25, 2011

Nagoya NA-771 Tests

I tested today one nagoya NA-771 antenna i have.
A search on the net revealed that the antenna has poor performance on UHF
I used my Anritsu site master antenna analyzer to test the antenna for VSWR at some bands.
Here is a sweep from 100MHz up to 500MHz:
Here is a VHF sweep:
And a UHF one:
Clearly the antenna has very high SWR on the UHF band.

VX-8GR Service manual / Technical supplement

Here is the link to the VX-8GR service manual for download, finally i found something.
I just hope i'll find the VX-8 one.

Please donate 1.000.000 euros cause i'm out. lol

Friday, June 3, 2011

Lenovo X300 freeze problem

I have seen many users complaining about their lenovo X300 laptop.
My friend has one and had the same problem, it wasn't even able to boot windows and froze up.
We decided to open it and check it out. Seems that the problem is on the hardware side rather on software.
The Intel SLAHZ LE82GS965 (it's a VGA-memory controller chip) needs a reflow or a reball. On the picture above you see a snapshot right before the reflow.After that the laptop works like a swiss clock without problems.

Below you can see another board from a Sony VGN-NR series laptop with vga problems, this was also solved by reflowing the Nvidia chip.