Pretty expensive for what it is. Pasternack wants over $7.50/ ft!! Yes it has double shield but the losses are 4.4dB at 100 MHz. LDF4-50 is cheaper and has less loss id you can put up with it being stiff heliax cable.
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LMR-400 for Ham Radio/cb radio
- Thread starter 1iwilly
- Start date
Pretty expensive for what it is. Pasternack wants over $7.50/ ft!! Yes it has double shield but the losses are 4.4dB at 100 MHz. LDF4-50 is cheaper and has less loss id you can put up with it being stiff heliax cable.
Wow. I gotta say that there is a whole lot of misinformation in some of these comments.
''LMR400 is copper clad aluminum"
"213 has braided shielding which is all you need for cb and hf"
To be absolutely 100% clear. The difference between ANY 213 and ANY 400 is that 400 has the 100% foil shielding as well as the copper braided shielding. It does not matter what type of radio you operate or what band....protecting your signal matters.
You can buy 213 in solid copper conductor, solid copper stranded conductor and copper plated aluminum....And the same goes for any 400 coax. The conductors all have their own characteristics.
''LMR400 is copper clad aluminum"
"213 has braided shielding which is all you need for cb and hf"
To be absolutely 100% clear. The difference between ANY 213 and ANY 400 is that 400 has the 100% foil shielding as well as the copper braided shielding. It does not matter what type of radio you operate or what band....protecting your signal matters.
You can buy 213 in solid copper conductor, solid copper stranded conductor and copper plated aluminum....And the same goes for any 400 coax. The conductors all have their own characteristics.
If the centre conductor changes such as from solid copper to stranded copper or copper plated aluminum then the designation also changes. All three types cannot be called RG-213. Perhaps RG-213 "type". RG-213 has a 13 gauge stranded centre conductor with a copper braid with 95% coverage.
$6.62/foot at Allied for M17/128 RG400. Ill never buy cable anywhere else. These folks are top notch.
https://www.awcwire.com/part.aspx?partname=m17/128-rg400
I'll NEVER buy any cable at $6.62/ft regardless of where it is. LDF4 is MUCH better and cheaper.
I wouldn't either. My point was Allied has lower prices generally. Ill never buy cable from ham/cb supply sites again.
I don't buy expensive ass coax just to use on cb. I use rg 213 and mini 8 and its good enough for me. Remember, cb Is hf and the loss factor is much lower than say, 144 mhz..
I suppose next someone will post "is coax length important?" Let's not go down that rabbit hole.
You get what you pay for... If you live in more harsh weather conditions, it pays in the long run to have better quality coax.... But to each there own
TMS LMR400 has a line loss attenuation of .644 dB./100 feet (3.28 wl) @ 27.385 MHz.. With 100W. input to the line, under IDEAL load conditions, 13.8W. of power is dissipated leaving only 86.2W. to be delivered to the input of the antenna/load. If you're using RG8-X, RG8-M, RG8-U, RG-213 or RF-9914 your line losses via attenuation will be greater, more power will be lost. RF-9913 is compatible with LMR400 with regard to power / transmission line loss.
RF shielding attenuation of RG-213 is only 40 dB., 90dB. for TMS LMR400. RG-213 has almost twice as much loss per foot than LMR400.
RG-213 @ 50 MHz. 1.6 dB. per 100 feet / 30.8% line loss.
LMR400 @ 50 MHz. 0.9 dB. per 100 feet / 18.7% line loss.
https://w4rp.com/ref/coax.html
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LMR400 has only 1.2 dB. loss per 100 feet @ 100 MHz. and not quite as pricey.
RG213 is ideal for HF frequencies below 30 mHz not at VHF at 50 MHz. LMR is designed to be superior over RG213 cable with less losses well above 30 mHz and beyond. I do use it for VFH/UHF where the coax losses increase significantly. 213 would be awful in the GHz region and LMR400 would be an improvement but still be lossy.
The differences in losses below 30 MHz and especially below 10 MHz is in fractions of a dB at 100ft lengths.
It appears your using the a worst case scenario comparing 2 coax types at a frequency where one obviously excels over the other.
Either coax can be used on HF but I prefer 213 for the bare copper core and solid polyethylene dielectric over foam.
LMR uses copper clad, aluminum, and also solid copper dependent on type used. Plus I hate that foil tape shield.
Also 213 has a better outer jacket which is stiffer but seems to hold up better in the drier SW climate where I live.
Those fractions of a dB on HF will never be noticed and basically like I said earlier, if numbers make you feel better, don't stop short of getting the absolute best you can like 7/8th Heliax.
"It appears your using the a worst case scenario comparing 2 coax types at a frequency where one obviously excels over the other."
No, i simply select the feedline based on seeing to it that attenuation from line losses don't eat up all of my precious transmitter power. RG-213 IS the worst case scenario at every frequency when compared to TMS LMR400.
https://www.timesmicrowave.com/DataSheets/CableProducts/LMR-400.pdf
RG-213 @ 50 MHz. 1.6 dB. per 100 feet / 30.8% line loss.
LMR400 @ 50 MHz. 0.9 dB. per 100 feet / 18.7% line loss.
If you (or anyone) can afford to waste 18.7 - 30.8W out of every 100W of input power then by all means, go for it. The above figures were for perfect load conditions referenced to the same line with 0 loss.
Ref: https://www.worldwidedx.com/threads/lmr-400-for-ham-radio-cb-radio.259636/page-3#post-749465
No, i simply select the feedline based on seeing to it that attenuation from line losses don't eat up all of my precious transmitter power. RG-213 IS the worst case scenario at every frequency when compared to TMS LMR400.
https://www.timesmicrowave.com/DataSheets/CableProducts/LMR-400.pdf
RG-213 @ 50 MHz. 1.6 dB. per 100 feet / 30.8% line loss.
LMR400 @ 50 MHz. 0.9 dB. per 100 feet / 18.7% line loss.
If you (or anyone) can afford to waste 18.7 - 30.8W out of every 100W of input power then by all means, go for it. The above figures were for perfect load conditions referenced to the same line with 0 loss.
Ref: https://www.worldwidedx.com/threads/lmr-400-for-ham-radio-cb-radio.259636/page-3#post-749465
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That was my point! Also I was quoting someone who said "lmr-400 is copper clad aluminum". Which yes you can find lmr-400 type coax in cca but he was saying that all lmr-400 is cca.