Best type of coax?

[HomerBB]

I'm not dropping a C-note on a $10 run of coax on any HF installation.
I will run RG6 before I spend for high dollar coax with similar attenuation at the low power I run. In fact, until this Wednesday, that's exactly what I've been running for months on my multiband wire. I moved it, shortened the run, and put it on RG8X.

Walmart.com 100' RG6 $9.97
Walmart.com 80' RG213 $105.90

>10× the price for 0.1 db difference @50 mhz.

I purposely chose Walmart to illustrate same source lower pricing. Before you go off on low quality Walmart remember the *.com is a drop shipping source just like Amazon.

 

[bob85]

I once ran a long run of rg58 laying on the ground to my antenna as a get me on the air at a new location with the only coax I had at the time,

From memory I measured 100w in for 38w at the antenna, not good so i cut a little off & ended up with 42w at the antenna,

I had no decent coax but I had mains cable so I moved my base amp to the bottom of the mast & turned the radio power up to get full output from the amplifier,

that gave me a little more than 98% of my power to the antenna,


The 58% loss on RX made no difference to what I could hear on 27mhz compared to coax with half the loss of rg213,

on UHF its a different story,
I could hear nothing but my own transmissions from a UHF handie when I put a commercial 4 stack uhf dipole at the end of that same long run of rg58.

 

[freecell]

"I doubt you'd notice it on the S meter as it's not even half a S point."

what i notice would blow your mind.

 

[codeman]

I get a new to me tube amplifier and was having problems with cb shop jumpers. So I asked a local licensed ham what he thought I should use so I went with lmr 240 jumpers. No problems since.

https://www.hamradio.com/detail.cfm?pid=H0-011966

 

[r carl]

I get a new to me tube amplifier and was having problems with cb shop jumpers. So I asked a local licensed ham what he thought I should use so I went with lmr 240 jumpers. No problems since.

https://www.hamradio.com/detail.cfm?pid=H0-011966

What kind of problems were you having?

 

[codeman]

What kind of problems were you having?

It was strange, but when I would key up I would not get any output. Changed a jumper and it was good, then it happened again. So I upgraded the coax and all is fine.

 

[r carl]

It was strange, but when I would key up I would not get any output. Changed a jumper and it was good, then it happened again. So I upgraded the coax and all is fine.

Could of there been a break in the center conductor?

 

[codeman]

Could of there been a break in the center conductor?

Probably so. I went through three of the "cheap" jumpers. All seems good now.

 

[Cam Tetzlaff]

LMR-400 or "equivalent" for feed line and LMR-240 or "equivalent" for all jumpers if it's a base setup.

LMR-240 for mobile setup.

This is what I have done for my two base stations and my mobile set up. I specifically went this route for the additional shielding that 400 and 240 has. Shielding is everything.

 

[Slowmover]

LMR-400 or "equivalent" for feed line and LMR-240 or "equivalent" for all jumpers if it's a base setup.

LMR-240 for mobile setup.

This is what I have done for my two base stations and my mobile set up. I specifically went this route for the additional shielding that 400 and 240 has. Shielding is everything.

In this case, routing is everything.

 

[Cam Tetzlaff]

In this case, routing is everything.

Yes, that too!

 

[Slowmover]

Yes, that too!

I apologize if it came off the wrong way.

Big truck installation means maybe a few feet “outside” from truck cab to west coast mirror arms. Highly-flexible (tight bends or wraps) with FME ends will be easiest assuming pre-made.

DIY, I’d look into what’s desired for an antenna feed-point choke. And a choke before the radio. (Noise treatment at each end of coax; three points on a cophase harness).

Ought to be a way to test the idea beforehand. A single line to one arm, then with & without toroids or other.

 

[Cam Tetzlaff]

I apologize if it came off the wrong way.

Big truck installation means maybe a few feet “outside” from truck cab to west coast mirror arms. Highly-flexible (tight bends or wraps) with FME ends will be easiest assuming pre-made.

DIY, I’d look into what’s desired for an antenna feed-point choke. And a choke before the radio. (Noise treatment at each end of coax; three points on a cophase harness).

Ought to be a way to test the idea beforehand. A single line to one arm, then with & without toroids or other.

All good man! I didn't take it bad.

 

[freecell]

bob85,

"From memory I measured 100w in for 38w at the antenna, not good so i cut a little off & ended up with 42w at the antenna."

@ 38W, feedline loss due to attenuation = 4.202 dB..
@ 42W, feedline loss due to attenuation = 3.767 dB..

 

[Smokinone]

I've been happy with my 9913F for the base antenna, a MFJ Super Penetrator. I use the mini-8 for jumpers in the house. I have some RG400 on the way, so I may make some jumpers from that and see what if any difference it will make.