BNC connector

hello ..
working on the 1.3 GHZ .. for a transmitter ..iwant to connect external antenna with the output from the last stage RF amp using BNC connector and cable...
any suggestion on the BNC connector to use..is there different types of bnc that work on different frequency bands ? its 50ohm matched output...

This one claims dc-to 18GHz:
http://www.atlantecrf.com/pdf/Attenuators%20-%20N%2C%20TNC%2C%20BNC%2C%207mm.pdf#search='BNCmax frequency'

Suhner BNC connectors work up to 4 GHz.
Never used over 2 GHz, on that frequencies I prefer N or SMA connector.

Mandi

I agree. BNC is unappropriate for frequency range above 1-2GHz.

Indeed there are BNCs for different frequency ranges:

1. High-quality RF BNCs

2. Low-quality low-frequency ethernet-cheapernet BNCs

It can work up to 4GHz.for higher frequency we use SMA,not BNC

Depends what you are using the BNC connector.
Can be used up to 10 - 12 GHz without any problem, if phase instability is not interesting (e.g. just connect some signal to some other point).
Can be normally used up to 2 GHz when phase stabilty counts (e.g. lower precision VNA), but not very sensitive to random changes.
Cannot be used at all when precision measurement is needed.
g579

is SMA better for 1.3 GHz range ? and for power level 30dBm ? 50 ohm matched ?

Hi,

Please find below a link to the origin and description of the BNC connector (and also some other popular connectors)

hxxp://www.johnsoncomponents.com/webapp/wcs/stores/Johnson/pdfs/RFguide.pdf

rgds,
Al

For sure SMA is much better than BNC, but much more epensive.
A BNC can be found for 0,5 Euro, instad a SMA can cost some 10 Euro.
It is 50 Ohm, it can handle about 50 W at 1,3 GHz ( depends on the company ) and the lekage is very low.
If your application is critical for sure change to SMA, otherwise ( for example WLAN, some small transmitters, etc ) use the BNC without any problem.
The problem with BNC is that the ground connection is not so stable ( overall under vibrations ) as the SMA, because the screen is connected just trough a spring and not threaded as the SMA.

Mandi

Hi AL,

The article above is a very nice and clean summary of RF connectors. I think everybody should read that at the beginning of his/her RF life. Thanks.
g579