LMR-400 VS 600 for 200 foot run 20- 10 meters

[AJAT]

I am designing an HF antenna set up. I have an existing tower on my property. I would need about 200 feet coax from the antenna to the shack., I am looking at putting up a 3 element yagi, 20,15,10 meters. I would like to run LMR-600. LMR-400 would be $260 cheaper. Would really notice a difference between the 400 and 600? I am running 100W. I may in the distant future get an amp, but no immediate plans. I would like to not have to run a new cable if/when I decide to get an amp.

 

[mmckenna]

20 meter band, 200 feet:
LMR-400 = 0.9dB loss. 81 watts make it to the antenna.
LMR-600 = 0.57dB loss. 87.6 watts make it to the antenna.

We know that QRP does pretty well with a small amount of power. The 6.6 watt difference is probably not going to be noticeable.

Consider that losses go up as frequency goes up.

10 meter band:
1.3dB loss/74 watts to the antenna
0.8dB loss/83 watts to the antenna

Again, not a huge difference.

If you ever plan on using this coax for VHF or UHF, it might make sense to go with the LMR-600. The LMR-600 will make a difference at 440MHz.

But consider most of the cost (either direct, or through effort) is in the actual installation of said cable. Better to do it once and go all the way than change your mind later and put twice as much labor into this. In other words, if dollars are not a concern…..

 

[mmckenna]

Forgot to add:

Below 30MHz, power ratings are:

LMR-600, up to 5500 watts.
LMR-400, up to 3300 watts.

So, no issues with legal limit amps.

 

[AJAT]

Thanks for the reply. The $260.00 difference does not seem like a lot, but as I start adding up all the extras (Rotator, Rotator cable, connectors, ground rod, water proofing.......) it adds up. I guess once I get my complete list I will decide which route to go, although right now I am leaning toward the 400. My UHF antenna will be much closer to the shack or on roof so no worries there.

Plus my new radio I just bought FTDX10 (Coming Monday, I cant wait )

 

[alcahuete]

I use LMR-400 for pretty much all my HF runs, and then hardline for the VHF/UHF. You aren't going to notice the difference between 400 and 600.

 

[mmckenna]

Yeah, I agree. You probably won't notice the LMR-400 vs. LMR-600 on HF. $260 that could be spent on better things.