Wireless Security Systems

[Robert Macy]

Anybody have experience with wireless security 4+ camera systems ?

Are these systems 'bluetooth' and fight for throughput?

Good ones for outdoor use?

Any URL with a block diagram?

I know, but google returns sales and eBay and Amazon, not information.

 

[Jeff Liebermann]

On Tue, 11 Oct 2011 11:15:58 -0700 (PDT), Robert Macy
<robert.a.macy@gmail.com> wrote:

Anybody have experience with wireless security 4+ camera systems ?

Yep. I bought a loser on eBay and now know what NOT to buy.

Are these systems 'bluetooth' and fight for throughput?

Huh? No Bluegoof in sight. What you're thinking of is 802.11b/g also
known as Wi-Fi. The problem is that 4 active Wi-Fi cameras will
occupy 100% of the available bandwidth in the 2.4GHz band. They will
also trash your 2.4GHz cordless phone, your wireless internet to your
laptop and iPhone. The picture will go nuts when you run the
microwave oven. Wireless cameras are a dumb idea. Use coax cable, or
get a pair of baluns and use CAT5 for the cameras. I switched to CAT5
and am living happily ever after.

Good ones for outdoor use?

Outdoor is always a problem because of temperature and potential water
damage. You can do ok by enclosing the camera in a heated enclosure
(to reduce lens fogging), but a real outdoor camera is always
prefered.

Any URL with a block diagram?

This weeks favorite vendor:
<http://www.securitycamerasdirect.com>

There's not much to it. Just 4-16 cameras, some coax or CAT5, a DVR
box where it all comes together, an ethernet connection to your
network, a local VGA monitor, a mouse, etc. I bought the bare DVR
without a hard disk drive and added my own at considerable savings.

A huge headache is the absolutely worthless software for remote
monitoring and searching the archives. The allegedly "free" software
continues to expire after 30 days, even though the vendor claims that
it's been fixed. The user friendly interface was apparently designed
for non-humans.

Hint: Spend you money on decent cameras. Pay attention to the
resolution spec. For outdoor, you'll need an (expensive) auto iris
lens. There are numerous web sites to help you calculate what size
lens to get. Connect a decent digital camera with a video output to
the DVR and compare the images with a cheap NTSC camera. If you can
actually recognize people on the cheap camera, it's probably ok.
However, it will rarely be as good as the digital camera.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[(PeteCresswell)]

Per Robert Macy:

Anybody have experience with wireless security 4+ camera systems ?

Are these systems 'bluetooth' and fight for throughput?

Good ones for outdoor use?

Any URL with a block diagram?

I know, but google returns sales and eBay and Amazon, not information.

I'm far from an expert - in fact I have been trying to climb the
same learning curve for over a year now.

Having said that....

Look at band width/resolution. My experience so far has been
that wireless cams (WiFi is the only method I've looked at) just
don't return good enough motion or detail to be useful.

Accordingly, I have been focusing on IP cams that work over
hard-wired Ethernet.

For allowing one to view cameras from afar, besides hooking into
the camera's native web page, the only app I have found so far
that seems to do the trick is WebCamXP.

--
PeteCresswell

 

[Jeff Liebermann]

On Tue, 11 Oct 2011 12:52:21 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:

On Tue, 11 Oct 2011 11:15:58 -0700 (PDT), Robert Macy
robert.a.macy@gmail.com> wrote:

Are these systems 'bluetooth' and fight for throughput?

Huh? No Bluegoof in sight. What you're thinking of is 802.11b/g also
known as Wi-Fi. The problem is that 4 active Wi-Fi cameras will
occupy 100% of the available bandwidth in the 2.4GHz band. They will
also trash your 2.4GHz cordless phone, your wireless internet to your
laptop and iPhone. The picture will go nuts when you run the
microwave oven. Wireless cameras are a dumb idea. Use coax cable, or
get a pair of baluns and use CAT5 for the cameras. I switched to CAT5
and am living happily ever after.

That wasn't very clear. Wireless security camera systems do not use
Wi-Fi (802.11). They use conventional NTSC analog transmissions on
approximately 1/4th of the 2.4GHz band. It's not VSB as the signal is
about 12MHz wide. There's no acknowledgements from the receiver, and
there's no listening on the channel to see if it's occupied. Just one
way broadcasting and interference to existing Wi-Fi systems. Sorry
for the muddle.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558