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best coax

"At 100 feet RG 213 has 1.2 dB loss on 30 mHz
If you get the good quality cable that is..."

100W in, 76W out.

"Aircom Plus has 0.55 dB loss on 30 mHz doble screened as well.
Lowering losses by more as half."

100W in, 88W out.

"Just for fun, Ecoflex 15 has 0.22 dB loss at 30 mHz per 100 feet."

100W in, 95W out.

not enough difference in either scenario to make or break a contact.
must be the radio hobbyists version of "trivial pursuit". it's a waste
of time and money. if you have 100' of 213 with the loss stated above
just increase power input to 132W and you'll have 100W out by the
time it reaches the antenna.

P.S. the PL259 is not a constant (fixed) impedance connector.
 
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are there better or lower loss pl259's than amphenols ? towernewbies you can order coax online from most cb/ham stores . some are pretty high on shipping and (i think) unreasonable for the cost to attach 259's for custom lengths . if you can do some soldering and have a multimeter for testing your work then consider ordering coax without conectors and attach your own . sparkys sells amphenol 259's for less than $2 and his shipping is very very reasonable . he doesnt seem to carry big coax though.....just rg8x . http://www.sparkyscbshack.com/catalog/item/2850813/2347581.htm
lmr400uf can be had @ RF Parts for $1.04 a foot . http://www.rfparts.com/coax.html id go for the stranded center conductor ultra-flex version rather than the solid core . thats just my opinion and we all know what opinions are like............
 
@ freecell

Depends on what you see as trivial pursuit....

As i wrote, most people spend lots of money on an antenna wich electrically is 5/8 or 6/8 and most have the same gain, but prices can be several 100 dollars different if the package and name is right.....

Loss works both ways as i wrote, loss will weaken reception as well.

Most of you guy's are willing to up the power an few watts from an standard box, but seemingly not realising the best gain is in your antenna system.

Translate the losses to stations using 1000 watts, losses then with just 100 feet RG213 are then 10 fold, several 100 watts lost as heat in the cable.
Using the largest cable this is just 50 watts, 150 watts difference

Just was has your priority i think, you can always buy an bigger P.A.
But that will not improve your reception.

That the PL259 connectors weren't guaranteed 50 Ohm is what i already knew for an few decades, it just adds to the losses if you have an bad batch, and the combined losses is what counts.

73

Cor
 
"Translate the losses to stations using 1000 watts, losses then with just 100 feet RG213 are then 10 fold, several 100 watts lost as heat in the cable."

+/- 240W to be more exact. though the amount of power loss increased by a factor of 10 the input power was also increased by the same amount. heating aside, 1.2db. of loss is the same whether we're talking about 100W in and 76W out or 1000W in and 760W out, the resulting power difference is only 1.2db., which i might add is not detectable or perceptible to anyone with normal hearing.
 
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LMR 400 is good stuff
the beginning of what i term the better stuff

the length of your run
and amount willing to spend
as well as willingness to work with the trickier less flexible stuff

factor it all together and chose your poison lol
 
With the price difference of something on the order of $2.00 per foot (just a guess, didn't look it up), that "gain" of maybe 25 watts costs a bit more than I'm willing to pay for it. And since it's very, very seldom that 25 watts power difference would even be noticeable to someone listening to that signal, is it really worth something like $200.00 difference in the cost of the feed line? Not to me, sorry.
As for the 'heating' (losses) of the feed line between that 1.2dB and 0.22dB, it may sound like a 'biggy', but it isn't. Same for the relative amounts of loss in signal being received. Most receivers have much more 'gain'/sensitivity than required to make up for that loss. The 'paper' numbers may seem impressive, but when translated to practical usage, and the human ear, it's just not very reasonable/cost effective. Keep in mind that this is at HF.
- 'Doc

(I'd rather spend that 'extra' $200 on beer, but that's just a personal preference.)
 
Working here from 160 meters up to 23 cm's here, above 30 mHz i use exclusively the 1/2 inch Ecoflex 15 even with the 65 foot runs i need.

If RG213 is your choice fine, i have no problem with that, it's your call.
An small signal that gets extra losses in the coax cannot be retrieved in the reciever whatever gain the frontend has or how good the DSP is, if it is below the noisefloor, it is gone.
27-30 mHz is at the high end of H.F, without skip in these times you need every help to get the stations in, one reason i changed the bandpass switching diodes in the FT 847 to ultra low noise Schottky diodes, adding an extra 6 dB lowering of the noisefloor.

When we're round the peak of the sunspot cycle it is an moot point, agreed, all signals then will be s9+
Even at the bottom of the cycle i work loads of stations on 10 meter, or 12 and 15.

Using an homebrew FD-4 with added 160 meter section you can expext on some bands an swr wich is not perfect, here that is an 1:2.2 as worst case.

Then an good coax does count.

Point i tried to show is that most CB stations will be trying to tweek every watt out of their radio or amp, only to see much wasted in lossy coax, maybe it is enough satisfaction to see your watt meter swing and forgetting you waste 20% of that power in the coax.

RG213 is available in many qualities, since it is not an protected name i see eyewatering cable come on the market with just an few strands of outer shielding etc.

The figures of loss were for good quality cable, in case of the bad quality cable add lots of extra losses.

In SSB an small difference might be the difference of understanding an station or missing it.
Licensed in 1977 be4 that many years on CB and always tinkering wit antenna's etc.

Most H.F contacts are worked with 100 watts, not needing the Heathkit SB-1000.
Even on the "lowly OCF"antenna at 50 feet flattop.
For 10/12/15the Imax 2000 can be used as vertical, got it free, added the ground radials for the different bands and it works just fine.
All fed with the better coax.

Everything above 30 mHz is N connectors.
At the end of the day if you are well informed you make the choice what will do for you.
I see too many CB stations invest large sums of money on an all band transciever and P.A. etc and skimp in the antenna system.
Read up ARRL or RSGB antenna books, Rothammel's antennabook ;)

Just my 2p

It's only justme :D
 
Make an connector on the beam, use for the short cable an more flexable piece of connecting coax.

Using self amalgamating tape i always tape connectors outside to prevent water ingress in connectors/cables even N connectors.

All 6/2/70/23 antenna's have n connnectors to wich the coax is connected.

the 6meter beam and 23 cm beam are homemade, the 11 element flexa yagi for 2 and the 23 element Flexa yagi for 70 both have standard N connectors and an teflon coax balun for 800 watts.
The X510 N from Diamond for 2/70 has an N connector as well.
N connectors for Ecoflex 15 are without need to be soldered.
 
Make sure you waterproof any conection, moist rain etc will ingress in the cable through capillary working and ruin the coax.

Good luck ;)
 
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(y)(y) This has been stated dozens of times on here.
Point i tried to show is that most CB stations will be trying to tweek every watt out of their radio or amp, only to see much wasted in lossy coax, maybe it is enough satisfaction to see your watt meter swing and forgetting you waste 20% of that power in the coax.

Everything above 30 mHz is N connectors. ( I also do the same)
At the end of the day if you are well informed you make the choice what will do for you.
I see too many CB stations invest large (insane) sums of money on an all band transciever and P.A. etc and skimp in the antenna system.
Read up ARRL or RSGB antenna books, Rothammel's antennabook.

i like lmr 400.theres probaly is better but this works great for me and in my budget range

Here is really good advice from a lot of different sources, but the last one says it all. Thanks guys for letting me borrow excerps from your post!!
 
You have seen the light Sir ;)

Everybody makes his/her choice, whatever you think works for you.
I spend about 1800 euro's on my antenna's and feedlines and connectors.

For radio i use the FT847 Collins filters, homemade TXCO, low noise Schottky diode bandswitch, temperature controled fans and some other mods.
Still puts out 100 watts as factory specs, as does the FT100 also modified.

If i need power i can flip the switch from the rebuild SB-1000 Heathkit.
Mostly i only need 100 watts.....
Makes you think, eh?
 
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