What are the difference between RG178 and RG316, do I really need to bother when it comes to pigtails? A qualified guess would be that the more expensive RG316 cable has less cable loss.

Hi ...

Considering a 1 meter long pigtail, 178 will introduce 2.6dB loss and 316 around 1.5dB at 3GHz. They´re silver plated, single braid, stranded inner conductor.

Both cables are ok untill 3GHz despite of some catalogs exibits loss figures till 5 or 6GHz.


Regards

This calculator provided by Times Microwave should help you when deciding what cable to use.

http://www.timesmicrowave.com/cgi-bin/calculate.pl

As Mramos pointed out, the amount of signal loss (attenuation) depends on the frequency being used.

Using the calculator with a frequency of 5745mhz you would see 2.1 dB of loss on the RG174 (similar to RG178) and 2.0 dB of loss on the RG316.

Installing the right cable in the beginning is very important and one of the best ways to insure a good quality link.

Remember that every 3 dB increase in signal strength is a doubling of signal.

If you're using anything but 2.4 or 900mhz you might consider LMR195, LMR 200, or LMR 240. Loss on the LMR 240 is less than half of the RG316 and it's better suited for outdoor environments....and the connectors are much easier to put on if your making the cable in house.

Hope that helps.

Thanks for the explanation, RG178 has a lot of loss comparing to the other cables.