Twisted pair cable difference with pictures

[vincenttor 0]

Well i am using Network cables instead of coax cable.

 

I have learned my lessons by buying cheap cable , the cables like 305meter for 80 euro.

i guess the problem is that they are made from aluminum with a copper coating.

 

I discovered it when i got image loss and problems when using it for the computer network.

what i did is take a multi/volt meter and i measured the cable resistance.

 

for example i used the orange pair and added them together on the end of the cable ( 300meter)

the value i got was high over 150 Ohm.

then i got the blue pair and measured, still the same cable and length.

the value i got was 40 Ohm.

and so on, this should be all the same or a bit difference.

 

then i bought a Belden Cat5e cable and it was allot better.

per accident i bought a FTP cable that means a cat5e cable but shielded with aluminum foil and from another brand.

the image difference was allot better compared to the old one.

 

i do not got images of the difference in France were i discovered it but today i changed my cables from 2 cams allready with the AMP tyco cat5 FTP cable.

you can see some difference in details

 

 

 

 

I did used the bnc-ftp adapters to get 75 Ohm instead of the 100 Ohm

the camera i used for testing is a cheap PTZ cam from ebay with 27x zoom.

plan is to change the cam for a better one with a higher LUX rate like 0.001 or something.

image is also captured with a Usb-Av in adapter instead of a DVR

 

So all i want to say with this is do not save money on the cable if you want to keep the best image possible

 

will change the cable next weekend from the samsung cam i use that has a better resolution to see the difference there and do some more tests with zooming on objects

[rory 0]

One is using Motion Jpeg in Firefox, the other using Javascript.

Neither will be good enough quality to really make a comparison.

 

Can you do it again but this time use the client software, or even the activeX in IE?

Thanks

 

But going by the 2 images above, although the Amco is when the sun is out, it still looks sharper. BTW the baluns also decide what kind of video picture you get in the end.

[Soundy 1]

for example i used the orange pair and added them together on the end of the cable ( 300meter)

the value i got was high over 150 Ohm.

then i got the blue pair and measured, still the same cable and length.

the value i got was 40 Ohm.

and so on, this should be all the same or a bit difference.

It's not really a valid comparison, as you're measuring only DC resistance, and video signals are going to be more affected by the capacitance of the wire pair.

 

then i bought a Belden Cat5e cable and it was allot better.

per accident i bought a FTP cable that means a cat5e cable but shielded with aluminum foil and from another brand.

the image difference was allot better compared to the old one.

I think you mean STP - shielded twisted pair (as opposed to the more common UTP - unshielded twisted pair).

 

So all i want to say with this is do not save money on the cable if you want to keep the best image possible

That's always a factor, although as rory mentions, design and build quality of the baluns can have a effect on the final image quality as well.

 

And FWIW, you don't have to use twisted-pair wire with baluns. I've run video and power over plain station wire (un-twisted, 22/4 wire), and I've used various types of speaker wire with baluns as well.

[vincenttor 0]

@rory:

 

i changed the javascript to motion jpeg but it did not do anything because the computer was allready offline

so the images are both taken with the javascript part.

 

i can not do a comparison anymore with the DVR card this is because i do not have the old wire anymore there.

 

@soundy,

 

no id did mean infact FTP cable

STands for : Foiled Twisted Pair

you also got Sftp and that is that the pairs are also foiled and the whole cable.

 

Did not knew about the measuring i thought it would be the problem.

it did gave problems with the internet and image.

but still isnt it strange, the same cable length , but the pairs all give a different Ohm value

( i am a DIY'r so i didnt knew about this)

 

 

with the next camera's i will use the DVR software and make a screenshot to compare then take a screen with the new cable.

 

thanks for the tip btw with the baluns, i understood that those meant if you only used network cable

[fa chris 0]

Copper coated aluminum wire? Sounds like a major fire hazard waiting to happen to me...

 

Outside of service poles, aluminum wiring is illegal in most places over here in the US.

[tomcctv 187]

I have learned my lessons by buying cheap cable , the cables like 305meter for 80 euro.

 

 

 

change your supplier if you think 80 euro is cheap thats £70 or $112 for 305m you should be getting two good drums for that money

[vincenttor 0]

Sorry for the late reply had allot of work to do.

 

Well here we have bad cables then for that money, ive called with 5 company's that sold the cheaper sorts and most of m did not knew if they were all copper or aluminum with copper layer.

no test rapports or something.

 

Today i wanted to test the camera and the composite adapter i used with the previous tests does not work anymore

goodbye test results...

 

So sorry but this topic can be closed or deleted.