Conductivity brass=copper?

[Pro-95]

Subject line says it all.

I've got a boatload of solid brass rods just waiting to become elements of my next antenna project.

So is brass = copper?

brass is usually copper/nickle so my immediate assumption is yes. Or at least close enough for an antenna element.

Btw I have several Yagi-Uda calculators I've downloaded and there is slight differences in calculations so my first Yagi-Uda antenna will be built to be variable. Seems as though if I built one 84 inches long with ~22 elements I could see a theoretical +17Db gain. :shock:

I also may whip together a 865Mhz ground plane while I'm waiting to head into town. Shouldn't take more than an hour and I could hook into my antenna switch to test it out.

 

[DonS]

Depending on its composition, brass is only 25-50% as conductive as copper.

If you're only concerned with electrical conductivity, aluminum would be much better than brass.

Metal       Conductivity (IACS)    Resistivity (n-ohm / m)
----------------------------------------------------------
Copper             100                     16.8
Aluminum          45-50                    26.5
Brass             25-50 (28)               35 (typ)

(the values for brass depend on its composition)

http://www.key-to-metals.com/Article79.htm
http://www.amm.com/index2.htm?/ref/conduct.HTM
http://www.allmeasures.com/Formulae/static/materials/

BTW: brass is an alloy of copper and zinc, not copper and nickel

-Don

 

[ka2mek]

Depending on its composition, brass is only 25-50% as conductive as copper.

If you're only concerned with electrical conductivity, aluminum would be much better than brass.

Metal       Conductivity (IACS)    Resistivity (n-ohm / m)
----------------------------------------------------------
Copper             100                     16.8
Aluminum          45-50                    26.5
Brass             25-50 (28)               35 (typ)

(the values for brass depend on its composition)

http://www.key-to-metals.com/Article79.htm
http://www.amm.com/index2.htm?/ref/conduct.HTM
http://www.allmeasures.com/Formulae/static/materials/

BTW: brass is an alloy of copper and zinc, not copper and nickel

-Don

Und Ya! das is correct Und also da veight iz much less undda not topple over and/or collapse Ya!And Nine da formula ("So is brass = copper?")
is daz nicht!Ya!
73-Robertmeister KA2MEK

 

[Halfpint]

Granted that it's only a Discone antenna but, I've got both an `early' RatShaft one *and* a `replacement' copy that I built after hassling with `falling elements' and trying to get replacements for the RatShaft that I made out of brass. While I had the RatShaft one `whole', which surprisingly enough was for almost a year after *finally* getting some replacment elements, I compared it to my brass `clone' and noted that any differences, if there *were* any they were beyond what I had to measure with, were basically non-existant *except* for the fact that the brass one is *still* up and *not* missing elements. (The hardest part of the project was designing and machining the co-ax connection! I ended up canniballizing an old `N' type connector I dug out of a piece of old surplus gear that I hadn't found a use for because it was a `style' I hadn't, and still haven't, seen before. Pretty much everything else was copied almost directly from the RatShaft antenna. [If I were to do it again there *are* a few things I'd do differently since I've learned a lot more about both antennas and machining since then. {WAN GRIN!}]) I suppose that there are probably antenna aps where brass wouldn't be suitable but they are also probably a bit `beyond' something like a `simple?' Discone or Groundplane? (One other thing... While brass is nice to machine it can be a real bear to bend. You *have* to anneal it at every point you are going to bend it and then make certain that you get the bend right the first time. [Don't ask me *how* I know. Let's just say that it was a real `learning experience?'! {WAN GRIN!}] Copper and alumininum are quite a bit more `forgiving'. Brass, OTOH, when it's done right sure looks great! {GRIN!} )

Just this `Olde Fart's' 2¢ worth. {GRIN!}