Coax Feedline Causing Loading Cap to Arc

[K5UJ]

Well Steve took the words right out of my mouth:  Plain old 213 is FB for in the shack jumpers. Using low loss coax for short runs on the lower end of HF can be an expensive overkill.

213 has 5 KV breakdown potential and the dielectric allows for fairly small bend radius.  I like it because it can seem to get pretty hot before the center migrates which is good for me because I stink at soldering UHF males, but I can put them on 213. 

The hard thing to find these days is good coax switches.  I lucked out and got two Bird 74 Coaxwitchs a few months ago for $75 each.  They needed some cleaning and lubrication but are working FB now. 

[WD8BIL]

Nothin' wrong with 9913 when installed and used right.
I have 4 runs up the tower and a run buried to the shack for 12 years now. The price was right on a 500 ft roll.

Do it right and it'll last a long time. gees!

[ke7trp]

And you prob done care about the 12 DB loss you now have since its been full of water every season    It still works!!! 


C

[Todd, KA1KAQ]

Nothin' wrong with 9913 when installed and used right.
I have 4 runs up the tower and a run buried to the shack for 12 years now. The price was right on a 500 ft roll.

Do it right and it'll last a long time. gees!

True story, Bud! Mine worked fine for years with zero water inside and no issues until I hit it with the mower. This was after I had moved, and had thrown something up quickly. Same as you probably, I got a 500' roll cheap and thought 'why not?' figuring I'd use it for VHF eventually.

Clark, though it's true 9913 has a rep for soaking up water, I'd still bet that in virtually all cases it's caused by improper installation or damage, even slight. Still, I'd not spend money on more of it for my current HF needs. 213 or similar will be the choice, though the 9913 served its purpose both as feedline and teacher for me over the years.

It's pretty bad when a piece of cable can outsmart you, that's all I'll say.

[ke7trp]

I am told its not the connectors. Its the material used on the jacket. It leaches the water in.  The ham club tested this after a bunch of guys said this was all due to not installing the connectors correctly.  They also cut the cable down, made new connectors and tested it again. It was real lossy.  Who the heck knows!  I can only puppet what I read Todd

C

[Todd, KA1KAQ]

I'm not doubting what you're saying at all, Clark. I've seen water in some of the stuff I have, so it does happen. Another section that was up for years had none. It was sealed up well and the connectors went on so tight they nearly wore the skin off my hands. Certainly isn't anything worthy of getting excited about, just something to learn from. 

[KM1H]

The 5KV rating on RG-213 is artificial and was done to suit some military chair warmer and carried over from WW2 RG-8 specs which can get rather ripe with age and become a resistor. Industry runs it at 10-12KV for decades. I use it at a loafing 3800V to the 2M amp and its been there over 25 years with HN connectors at both ends.

Carl

[Todd, KA1KAQ]

I have access to some new AN RG-98/U which I think is the equivalent of or replaced by RG-214. It's currently installed on my 80m dipole and seems to do the job. The dielectric doesn't appear at all discolored, so I'm going to guess it's okay to use. A buddy has a 500' roll from the military.

[W2VW]

Rented a hi-pot tested two summers ago. It came with a probe made out of RG-8 solid dielectric. Worked FB at 40 kv.

The 5KV rating on RG-213 is artificial and was done to suit some military chair warmer and carried over from WW2 RG-8 specs which can get rather ripe with age and become a resistor. Industry runs it at 10-12KV for decades. I use it at a loafing 3800V to the 2M amp and its been there over 25 years with HN connectors at both ends.

Carl