[Elecraft] Other: Can you run coax inside metal conduit?

[Fred Jensen]

OK. Lived for 38 years in a house started in 1925.  Knob-tube wiring.  
You can run coax in metal conduit but NOT with power wiring.  If the 
load on the coax is unbalanced, RF current will likely flow on the outer 
surface of the shield and metal conduit will probably change the SWR. 
[Because of the "skin effect" that confines alternating current to the 
outer surface of conductors, coax really has three "conductors" ... 
center, inner surface of shield, and outer surface].  I'd be surprised 
if you saw any interactions with or without conduit but it would make a 
run of multiple coax cables a lot neater.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

Jerry Moore wrote on 6/12/2024 10:05 AM:
>
> HIHI, the house was built in 1960 and the feeds are a huge bundle of 
> wires loosely run across the ceiling of the basement INCLUDING a 
> copper water pipe (cringe). I’m in the process of re-routing the water 
> pipe and looking for a safer way to support the wires. Just a ton of 
> work. My intent with the conduit is to keep HF/UHF/VHF around the coax 
> from getting into the electricals or vice versa.
>
> *From:*Fred Jensen <k6dgwnv at gmail.com>
> *Sent:* Wednesday, June 12, 2024 12:16 PM
> *To:* Jerry Moore <jermo at carolinaheli.com>
> *Cc:* Elecraft at mailman.qth.net
> *Subject:* Re: [Elecraft] Other: Can you run coax inside metal conduit?
>
> Yes.  You said "don't ask," but what interactions are you attempting 
> to avoid?
>
> 73,
>
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
> Jerry Moore wrote on 6/12/2024 8:45 AM:
>
>     I have 30' run through my basement and want to eliminate potential interaction between the coax and power wires in the same area (don't ask). Is there any problem running coax for HF through metal coax?
>
>     Thanks in advance.
>
>     Yes, I decided to keep my K3S.
>
>     AE4PB
>
>     Jerry Moore
>
>     ______________________________________________________________
>
>     Elecraft mailing list
>
>     Home:http://mailman.qth.net/mailman/listinfo/elecraft
>
>     Help:http://mailman.qth.net/mmfaq.htm
>
>     Post:mailto:Elecraft at mailman.qth.net
>
>     This list hosted by:http://www.qsl.net
>
>     Please help support this email list:http://www.qsl.net/donate.html
>
>     Message delivered tok6dgwnv at gmail.com <mailto:k6dgwnv at gmail.com>  
>