Hi all,

I've got 8 cameras around my pub..  a couple are jittering now and again.
As in the picture will jump down then up by one line of the display.

Any ideas what is causing this ? The cams are connected using BNC and RG59
coax (is this the right stuff) Not all of them jitter and even a test cam
with a short lead and seperate powersupply sometimes jitters.

Doing my head in.. any ideas?

ps. It's a PC based XVision capture card with upto 16 cams.

Coax is a shared networking medium so all cameras transmitting will be 
contending for time on the wire.  I'd suggest connecting the cameras with 
Cat5e (if possible) and RJ45 to an ethernet switch where each device will 
have dedicated network bandwidth.  In effect, it wll give 100Mb/s to each 
camera instead of the 10Mb/s shared between all cameras in your current 
setup.  16 port 10/100 switches aren't too expensive either - 
http://www.ebuyer.com/customer/products/index.html?rb=15428527720&action=c2hvd19wcm9kdWN0X292ZXJ2aWV3&product_uid=54751

Mike


"Doz"  wrote in message 
news:1rwohxt1j1e9s.dzv8cfhxh8g4.dlg@40tude.net...
> Hi all,
>
> I've got 8 cameras around my pub..  a couple are jittering now and again.
> As in the picture will jump down then up by one line of the display.
>
> Any ideas what is causing this ? The cams are connected using BNC and RG59
> coax (is this the right stuff) Not all of them jitter and even a test cam
> with a short lead and seperate powersupply sometimes jitters.
>
> Doing my head in.. any ideas?
>
> ps. It's a PC based XVision capture card with upto 16 cams.

On Sun, 22 Jan 2006 14:30:54 -0000, Mike Powell wrote:

> Coax is a shared networking medium so all cameras transmitting will be 
> contending for time on the wire.  I'd suggest connecting the cameras with 
> Cat5e (if possible) and RJ45 to an ethernet switch where each device will 
> have dedicated network bandwidth.  In effect, it wll give 100Mb/s to each 
> camera instead of the 10Mb/s shared between all cameras in your current 
> setup.  16 port 10/100 switches aren't too expensive either - 
> http://www.ebuyer.com/customer/products/index.html?rb=15428527720&action=c2hvd19wcm9kdWN0X292ZXJ2aWV3&product_uid=54751
> 
> Mike
> 
> 
> "Doz"  wrote in message 
> news:1rwohxt1j1e9s.dzv8cfhxh8g4.dlg@40tude.net...
>> Hi all,
>>
>> I've got 8 cameras around my pub..  a couple are jittering now and again.
>> As in the picture will jump down then up by one line of the display.
>>
>> Any ideas what is causing this ? The cams are connected using BNC and RG59
>> coax (is this the right stuff) Not all of them jitter and even a test cam
>> with a short lead and seperate powersupply sometimes jitters.
>>
>> Doing my head in.. any ideas?
>>
>> ps. It's a PC based XVision capture card with upto 16 cams.

I should of mentioned that the cams hac a coax cable each and are analogue
and not network cams.

On Sun, 22 Jan 2006 14:33:25 GMT, Doz wrote:

> On Sun, 22 Jan 2006 14:30:54 -0000, Mike Powell wrote:
> 
>> Coax is a shared networking medium so all cameras transmitting will be 
>> contending for time on the wire.  I'd suggest connecting the cameras with 
>> Cat5e (if possible) and RJ45 to an ethernet switch where each device will 
>> have dedicated network bandwidth.  In effect, it wll give 100Mb/s to each 
>> camera instead of the 10Mb/s shared between all cameras in your current 
>> setup.  16 port 10/100 switches aren't too expensive either - 
>> http://www.ebuyer.com/customer/products/index.html?rb=15428527720&action=c2hvd19wcm9kdWN0X292ZXJ2aWV3&product_uid=54751
>> 
>> Mike
>> 
>> 
>> "Doz"  wrote in message 
>> news:1rwohxt1j1e9s.dzv8cfhxh8g4.dlg@40tude.net...
>>> Hi all,
>>>
>>> I've got 8 cameras around my pub..  a couple are jittering now and again.
>>> As in the picture will jump down then up by one line of the display.
>>>
>>> Any ideas what is causing this ? The cams are connected using BNC and RG59
>>> coax (is this the right stuff) Not all of them jitter and even a test cam
>>> with a short lead and seperate powersupply sometimes jitters.
>>>
>>> Doing my head in.. any ideas?
>>>
>>> ps. It's a PC based XVision capture card with upto 16 cams.
> 
> I should of mentioned that the cams have a coax cable each and are analogue
> and not network cams.

They are essentially composite video output into RG59 coax then back to the
multiport capture card. 8 Cams and 8 cables.

But when the Coax returns to the PC - it is the common "negative", that all 
the cameras share.  Being wired seperately doesn't change this.  Might be 
worthwhile getting a loan of a monitor and hooking it up to the worst camera 
using a T piece BNC connector, to see if its the cams at fault.

-- 
Regards


M Millar

"Doz"  wrote in message 
news:1jwt8crs6ujo4.1p6vqei2fqavs$.dlg@40tude.net...
> On Sun, 22 Jan 2006 14:30:54 -0000, Mike Powell wrote:
>
>> Coax is a shared networking medium so all cameras transmitting will be
>> contending for time on the wire.  I'd suggest connecting the cameras with
>> Cat5e (if possible) and RJ45 to an ethernet switch where each device will
>> have dedicated network bandwidth.  In effect, it wll give 100Mb/s to each
>> camera instead of the 10Mb/s shared between all cameras in your current
>> setup.  16 port 10/100 switches aren't too expensive either -
>> http://www.ebuyer.com/customer/products/index.html?rb=15428527720&action=c2hvd19wcm9kdWN0X292ZXJ2aWV3&product_uid=54751
>>
>> Mike
>>
>>
>> "Doz"  wrote in message
>> news:1rwohxt1j1e9s.dzv8cfhxh8g4.dlg@40tude.net...
>>> Hi all,
>>>
>>> I've got 8 cameras around my pub..  a couple are jittering now and 
>>> again.
>>> As in the picture will jump down then up by one line of the display.
>>>
>>> Any ideas what is causing this ? The cams are connected using BNC and 
>>> RG59
>>> coax (is this the right stuff) Not all of them jitter and even a test 
>>> cam
>>> with a short lead and seperate powersupply sometimes jitters.
>>>
>>> Doing my head in.. any ideas?
>>>
>>> ps. It's a PC based XVision capture card with upto 16 cams.
>
> I should of mentioned that the cams hac a coax cable each and are analogue
> and not network cams.