On Tue, March 21, 2017 10:50 am, John R Pierce wrote:
> On 3/21/2017 5:02 AM, ken wrote:
>>>
>> Those have worked for me as well. Their range, however, is a third or
>> half as much as a normal wifi device.
>>
>
> in general, the back of a server, buried under all the cables, and right
> up against the metal box is a lousy place for an RF antenna...
Agree. But it is even worse: iron is the worst case to have near GHz
frequency antenna: it is conductor, but not the good one, hence it will
eat up RF dissipating RF energy... Be it aluminum or copper, they will be
just reflecting RF, thus creating funny ("interference") radiation
pattern, but they will not dissipate RF energy. Similar "bad environment"
for RF antennae was found in macbook titanium: antenna openings were in
plastic frame, the last for better paint adhesion was metallized, first
layer of metal film deposited on plastic is usually nickel, which is
magnetic (with poor magnetic quality at 2.4 GHz), and poorly conductive.
That is why macbook titanium had worst WiFi one ever had seen in laptops.
Valeri
>
> --
> john r pierce, recycling bits in santa cruz
>
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> https://lists.centos.org/mailman/listinfo/centos
>
++++++++++++++++++++++++++++++++++++++++
Valeri Galtsev
Sr System Administrator
Department of Astronomy and Astrophysics
Kavli Institute for Cosmological Physics
University of Chicago
Phone: 773-702-4247
++++++++++++++++++++++++++++++++++++++++