Skin depth for 60 Hz is 8 mm. So that would yield a wire of 16 mm diameter before the skin effect would start to be a factor. Pretty large wire.
From: Bill Prince Sent: Tuesday, November 03, 2015 7:00 PM To: [email protected] Subject: Re: [AFMUG] using heliax for DC power up tower? Doesn't something like 90% of the current flow through the surface of copper wire? If that's true, a heliax of X diameter should flow 90% of a solid copper wire of the same diameter. bp <part15sbs{at}gmail{dot}com> On 11/3/2015 12:44 PM, Chuck McCown wrote: Depends on the size of the heliax. The larger stuff has a tube as center conductor. In any event just calculate the cross sectional area of the copper of the center conductor and you can compare that with a wire gauge chart. From: Adam Moffett Sent: Tuesday, November 03, 2015 1:08 PM To: [email protected] Subject: Re: [AFMUG] using heliax for DC power up tower? For equivalent wire gauge would you just compare the center conductor diameter to a wire gauge chart? On 11/2/2015 6:51 PM, Chuck McCown wrote: It is pretty easy to insert and remove power from a coax that also has RF on it too. Just a choke coil and capacitor at both ends. If you want details give me the frequency and what kind of power and I will design it for you. From: Jaime Solorza Sent: Monday, November 02, 2015 4:49 PM To: Animal Farm Subject: Re: [AFMUG] using heliax for DC power up tower? Yep .we used. LMR 400 to power custom made receive amps for WMux radios we modified long time ago. Jaime Solorza On Nov 2, 2015 3:51 PM, "Chuck McCown" <[email protected]> wrote: Just make sure if you hook it up to 120 VAC main current you don’t put the hot wire on the outer conductor of the coax... From: Ty Featherling Sent: Monday, November 02, 2015 3:43 PM To: [email protected] Subject: Re: [AFMUG] using heliax for DC power up tower? Thanks all, great solution Josh! -Ty -Ty On Mon, Nov 2, 2015 at 4:38 PM, Chuck McCown <[email protected]> wrote: You can run DC or AC over it. Think of it this way, 1000 watt ham radio puts 223 volts AC (at RF frequencies) on the coax and everything is just fine. All CATV systems put 60 or 90 volts AC on the line to power the amps. From: Ty Featherling Sent: Monday, November 02, 2015 2:09 PM To: [email protected] Subject: [AFMUG] using heliax for DC power up tower? Any reason I couldn't use 1/4" heliax I already have in place up a tower to run power to a POE switch? This is the stuff: https://www.tessco.com/products/displayProductInfo.do?sku=469162 -Ty
