75 ohm cable with 50 ohm BNC connectors
75 ohm cable with 50 ohm BNC connectors
(OP)
I am wondering if there is a large impact with using a 50 ohm BNC with a 75 ohm cable. We are using this with about a 50kHz signal. Is the dB drop going to be anything to worry about???
Thanks in advance for your help.
Thanks in advance for your help.





RE: 75 ohm cable with 50 ohm BNC connectors
But 50 kHz is so low that you're not likely to notice the reflections over any reasonable length of cable.
That's why nobody worries about the characteristic impedance of audio connectors. 50 kHz is nearly audio.
RE: 75 ohm cable with 50 ohm BNC connectors
One way to make RG-59 or RG-6 cable fit onto a BNC is to use the normal F-connectors (easy) and then F-to-BNC adapters (easy).
RE: 75 ohm cable with 50 ohm BNC connectors
You're probably going to have trouble with the center conductor if you are using crimp BNC connectors. It's thinner in 75 ohms and may not attach correctly.
If you are soldering the connectors it's not much of an issue.
RE: 75 ohm cable with 50 ohm BNC connectors
Plugging a 50R jack into a 75R socket expands the centre receptacle too much & it is unreliable thereafter with 75R jacks.
RE: 75 ohm cable with 50 ohm BNC connectors
RE: 75 ohm cable with 50 ohm BNC connectors
http://www.gigatronix.com/pdf/BNCz50Vsz75.pdf
Here are a couple of tidbits:
"The BNC connector was designed as a 50 ohm connector for military applications and requires a modification to the interface to create a 75 ohm connector. To achieve this the dielectric is either entirely removed or reduced to a very thin wall..."
"The use of 50 ohm connectors on 75 ohm cable with analog
signals has little or no distortion effect at frequencies below 600MHz"