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Posted By: stan security - 03/20/02 12:46 AM
Well today i looked at a job to replace a piecs of coax cable for a security camera . MY question is can i use replace the BNC connectors with regular coax connectors ?
Will this be bad?
Posted By: NJwirenut Re: security - 03/20/02 02:09 AM
What exactly are "regular coax connectors"? Do you mean "F" connectors like you see on CATV equipment? "UHF" connectors like you see on ham radio gear? "TNC"s like mobile phones use? "N" connectors like satellite TV and test equipment use? "RCA" plugs ala cheap consumer video equipment?

BNC's are pretty much the standard for CCTV and datacom stuff. Nice constant impedance, easy to mate/demate, and even somewhat weather-resistant when mated. Widely available, in crimp-on (recommended), solder clamp, and twist-on (avoid these) versions.

I guess you could use different connectors for video, but you will need adapters to connect to the cameras, monitors, switchers, etc., which will all have BNCs on them. By the time you buy the adapters, you might as well have used the proper plugs to begin with. If you use some kind of non-standard connector, whoever is working on the system after you will be cursing you under their breath when they have to change something out in the future. [Linked Image]

Whatever you use, you will need a connector and cable with a 75 ohm impedance, in order to get a decent picture with minimum distortion.

[This message has been edited by NJwirenut (edited 03-19-2002).]
Posted By: hal9000 Re: security - 03/20/02 04:10 AM
Right-on Wirenut. This guy knows his video. And I will agree twist on BNC's are junk.
Posted By: mamills Re: security - 03/20/02 06:44 PM
Stan:
I agree with Wirenut and Hal. If you need to replace the BNC connector, do so with a good quality BNC crimp-on type. Try to stay away from adaptors if at all possible. Any time you have to insert an adaptor in a video or audio circuit, you introduce a potential "weak spot" which will eventually cause trouble.

Mike (mamills)
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