I recently bought a tri-band (TBJ-1) from Ed Fong. He said RG-8 was fine up to 50 feet; after that, he said LMR400 or better would be necessary. I bought 42.5 feet of the RG-8 and it does appear to be awfully thick for a 10W TYT TD-UV8000D radio. But a 20-25W or more should may be okay for mobile radio used as a home station.
So what do you think? Should I send it back? I don't have a FCC license yet, so I'm uncomfortable transmitting.
Coaxial cable losses go up as length increases. Losses also go up as frequency increases.
RG-8 should work, but you can easily do better. LMR-400 is a good -middle-of-the-road- option.
If your plan is to use 70cm frequently, and you want weak signal performance, I'd step up to LMR-400 or better. If you are just going to be using repeaters that are local to you, RG-8 will be sufficient.
Consider your budget. LMR-400 will be more expensive, LMR-600, even higher cost.
Consider cable routing. LMR-400 is a stiffer cable. It can also put a lot of stress on the antenna connector if you try to connect it directly to the back of the radio. It's recommended to use a short jumper to transition from the heavier cable to the radio.
Consider your grounding/lightning protection. If you are running an antenna outside, or even up in the attic, you should, at minimum, be looking at the National Electric Code.
Consider your long term needs. RG-8 might be fine as a new ham, but as your interests change, you may want something better. Easier to buy the right stuff now rather than pay twice/install twice.
Your choice. RG-8 will work, but it's kind of the minimum you'd want in an application such as yours.
