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If you look inside a decent quality modem you'll
see two blue capacitor looking parts soldered on the board. These varistors
protect the modem from electrical surges coming in from the phone line. If you
look at the boards on the SB outdoor radios no such varistors exist. So, I ask
why not? If SB units had these would they be much better at dissipating static
charges in the ethernet before damaging the radio?
We've had terrible problems with induced charges in
the ethernet that runs from the outdoor unit to the indoors. We've seen the
ethernet side of ABO's and APPO's blow out. We've seen the WAN port of routers
blow out and we've seen the charge travel through the router and zap the NIC's
in the PC as well. So, for those of you who are new to installs and live in
areas where electrical storms exist, you have no choice but to come up with a
grounding solution. This is a very big deal not just because of the need to
prevent equipment damage but also because a good grounding system can increase
the WISP's cost to do an install by a couple of hundred dollars if you consider
both parts and labor. The problem is if you use SB equipment, there is no
provision on SB radios to facilitate setting up a decent grounding system. In
fact, because the ethernet that comes with the unit is unshielded, it can be
argued the SB outdoor radios are improperly designed to address the 'induced
charges in the ethernet' problem.
I know the subject of 'grounding' has been beaten
to death on this list but there seems to be many opinions on the correct way to
do grounding and it is not really obvious to us as to the best way to
go....and SB offers very little help and advice on this. You can go broke
buying coax lightning protectors and ethernet surge protectors and shielded CAT5
and on and on.
Clearly, putting the radio outside complicates the
grounding situation. This negates the advantage of the outdoor radio. So, SB it
is in your best interest, if you want to sell lots of outdoor units, to really
solve this problem. I hear you are going to sell a beefed up PowerShot
w/lightning protection but it will cost extra (bad idea). It is in your best
interest that your units don't get easily zapped as is the case now.
These are the things I know of that can be done or
need to be implemented in the outdoor radios:
1. Redesign the radio with an internal connection
system for CAT5 (maybe a punch down block...I dunno).
2. Metalize the radio enclosure.
3. Publish an installation spec that leaves no
doubt as to what constitutes a proper grounding system.
4. Improve the design of the ethernet circuity so
that it is more resistant to static, such as the use of varistors.
Regards,
Bobby Bounds
Airwave Internet
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