Which is a better coax

[Bonkk083]

Which is the better coax for 50 feet and less rg8x, rg58, rg213, I mainly listen to frequencies in the 150's

 

[dave3825]

I will let someone more experienced chime in on the losses between each. I use rg6 as its cheap and achieves what I need it to.

But whatever you do, make sure you rotate it.

Rotating your coax: A guide for newbies

Everyone knows that the coax is the most important part of a scanner antenna system. What many people forget is that, like the tires on your car, you need to rotate the coax from time to time. Spring is the optimum time to rotate the coax for most people, when it is warmer than winter and not...

forums.radioreference.com

 

[prcguy]

Which is the better coax for 50 feet and less rg8x, rg58, rg213, I mainly listen to frequencies in the 150's

RG-213 is the best of the coax mentioned for a 50ft run and by a lot depending on frequency range. For short jumpers under a few feet I would use RG-58 over RG-8X.

 

[Bonkk083]

RG-213 is the best of the coax mentioned for a 50ft run and by a lot depending on frequency range. For short jumpers under a few feet I would use RG-58 over RG-8X.

Is the rg213 thicker than rg11 or rg8x, I forgot to mention lmr 400 on which is better

 

[belvdr]

Here are a couple of handy charts to reference. Both have data that can be used to make a choice.

DX Engineering Coax Specifications

Universal Radio Coax Performance

 

[Bonkk083]

Here are a couple of handy charts to reference. Both have data that can be used to make a choice.

DX Engineering Coax Specifications

Universal Radio Coax Performance

Do you go by the lower db are more kw

 

[belvdr]

Do you go by the lower db are more kw

Depends on if you're receiving or transmitting. If you notice, the longer runs at higher frequencies attenuate (i.e degrade more) and take less power.

For receiving only, you want less attenuation (read less db/100 ft of coax).

 

[Bonkk083]

Depends on if you're receiving or transmitting. If you notice, the longer runs at higher frequencies attenuate (i.e degrade more) and take less power.

For receiving only, you want less attenuation (read less db/100 ft of coax).

Which coax would you prefer that has less loss for receiving 150 mhz range

 

[n5ims]

Do you go by the lower db are more kw

Lower dB (assuming that all are listed against the same reference. For example, dbi shows larger numbers than dbd for the same level. Typically coax loss charts all use the same reference so this isn't a problem. When comparing antennas, you'll typically see the gain listed in either db, dbi, and dbd. The db number doesn't provide a reference so you should assume dbi just to be safe. The dbi number is referenced against a theoretical antenna that doesn't exist in reality but used by engineers as a standard reference. The dbd number is referenced against a standard dipole antenna that can actually be built and used. The dbd number is 2.15 units smaller than the dbi number so it may appear to have more gain when it actually doesn't.

Is the rg213 thicker than rg11 or rg8x, I forgot to mention lmr 400 on which is better

RG8, RG213, RG11, and LMR400 are generally about 1/2" in diameter. RG8x is smaller at about 1/4" in diameter. The specs on all of them are different (even if they are the same diameter) due to other factors. Use a good coax loss chart or calculator when selecting your coax. Be aware that there are several different types of most of these RG type coaxes and you can't assume that one brand's RG8 is the same as another brand's RG8. Also note that even within the same brand, they may have different types of RG8 with different loss or other specs. (Note: I'm using RG8 as an example here and the same goes for other types. Also note that RG8 is vastly different than RG8x so treat them as totally different types of coax.)

 

[belvdr]

Which coax would you prefer that has less loss for receiving 150 mhz range

For 50 feet, I doubt you'll see much of a a difference with any of the coax you mentioned. Typically what I do is use a low-loss cable through the walls and up to a wall jack, like LMR400 or LMR600. From there, I use a smaller, more flexible, patch cable like RG-8 to go from the wall to the radio.

 

[n5ims]

Which coax would you prefer that has less loss for receiving 150 mhz range

That would depend on the length of your run and your installation. For the typical hobbyist with a run between 50 and 100 feet long, a quality brand of LMR-400 would be a good option. This is a fairly cost-effective type of coax for this use and should serve you well. Avoid the off brands though since you may get something that appears to be LMR-400 but is of very poor quality and generally a waste of money. Times Microwave Corporation is one of the go-to brands. I'd avoid most of those on eBay and if the price is much lower than others, you're probably getting some low quality knock off stuff of questionable quality.

Also note that LMR-400 is a pretty stiff coax and it's generally best to use a short jumper between the coax run and your radio, especially if your radio uses SMA connectors or is a hand-held radio design. You'll break your antenna connector due to the strain from the stiff and heavy coax. A short jumper of RG-58 (3 to 6 feet long) will help save your radio without adding much additional loss.

 

[Edelweiss]

Let me offer some real heretic advice, 75 Ohm satellite coax! Very low loss, low cost and don't worry about the "impedance mismatch", god knows what your radio's input impedance is anyway. Need to find some F connector "adaptors" on ebay You may laugh.... , think what you want! I mean LMR400 is nice, fat and expensive but you don't transmit. I bet you won't notice the difference - other than what's left in your wallet!

 

[Bonkk083]

For 50 feet, I doubt you'll see much of a a difference with any of the coax you mentioned. Typically what I do is use a low-loss cable through the walls and up to a wall jack, like LMR400 or LMR600. From there, I use a smaller, more flexible, patch cable like RG-8 to go from the wall to the radio.

I have used radioshack 50 feet rg58 in the past it did pretty good, are they any need to get an more expensive coax to tell the difference

 

[belvdr]

I have used radioshack 50 feet rg58 in the past it did pretty good, are they any need to get an more expensive coax to tell the difference

If that's what you're currently using and don't notice any issues, I wouldn't worry about it.

 

[belvdr]

Let me offer some real heretic advice, 75 Ohm satellite coax! Very low loss, low cost and don't worry about the "impedance mismatch", god knows what your radio's input impedance is anyway. Need to find some F connector "adaptors" on ebay You may laugh.... , think what you want! I mean LMR400 is nice, fat and expensive but you don't transmit. I bet you won't notice the difference - other than what's left in your wallet!

That's probably RG-6. It'll work fine, but I'm not sure I would call it low loss. There are better options, especially for long runs and/or if you have weak signals.

 

[Bonkk083]

If that's what you're currently using and don't notice any issues, I wouldn't worr

If I ever needed to replace the rg58 what should I go with

 

[belvdr]

If I ever needed to replace the rg58 what should I go with

RG-8

 

[mmckenna]

If I ever needed to replace the rg58 what should I go with

The best you can afford, depending on your own reality. No one can tell you unless you give us a ton of details, especially about your budget.

Best thing to do is start plugging in information on this page right here:

Coax Calculator

Look at how the dB loss changes. More expensive/larger coax will have less loss. Less loss means more signal will get from your antenna to your radio.
But, don't get hung up on numbers. Seriously. You won't notice a 1dB difference. And the only place this really comes into play is if you are really trying to suck in weak signal stuff.

Larger coax = less loss. Less loss = more signal to your radio.
Larger coax = more money. Larger coax = harder to install.
Larger coax also puts a lot of strain on antenna connectors, so unless you are using a small diameter cable, you need to figure in using a short whip of smaller/more flexible cable.

For 50 feet, I would not get hung up on this too much. Unless you have a huge antenna system and something much more sensitive than a consumer scanner, you'll just be chasing numbers.

 

[KB4MSZ]

But whatever you do, make sure you rotate it.

Here we go....

 

[Edelweiss]

I barely notice, if not in direct comparison, a 6 dB difference.... I'd say impossible to make any judgement in a non-lab fluctuating short term signal world of e.g. the airbands... Also of course depends on many other things eg. how big is the signal in the first place ... As with any hobby spend as much as you like as long as you can justify it to yourself... Feels good to have nice coax, I admit! But you're not a pro where you need to meet requirements... Find a scanner with a calibrated RSSI... good luck! Compare with your nearest ATIS perhaps, preferably UHF or ideally a steady FM signal or a dead carrier, maybe a 70 cm amateur beacon or repeater carrier. What's more important than the couple of dBs is to make sure you have not got a rotten antenna, rotten connectors or worst, water in the coax... Avoid "UHF" connectors at all cost!