[TowerTalk] Loading Coils

[Gary K9GS]

Nickel is also difficult to solder to.73,Gary K9GS
-------- Original message --------From: "jim.thom jim.thom at telus.net" <jim.thom at telus.net> Date: 8/2/25  2:53 PM  (GMT-06:00) To: towertalk at contesting.com Subject: [TowerTalk] Loading Coils Date: Fri, 1 Aug 2025 15:19:10 -0700From: David Gilbert <ab7echo at gmail.com>To: towertalk at contesting.comSubject: Re: [TowerTalk] Loading CoilsNickel has about 4 times worse electrical conductivity compared tocopper, and the skin depth at 30 MHz is about 20 times thinner (about 12microns for copper versus about 0.65 for nickel).? ChatGPT tells me thatstandard nickel plating is roughly 5 to 10 microns thick , and that evenlow cost nickel plating is typically 1 to 2 microns thick.The math agrees with you.I wonder if anyone has made measured comparison of his coils versus asimilar copper one.Dave? ?AB7E##  nickel plated,  He's joking right ?  Years ago, I replaced the silverplated copper tubing coil in a hb amp with an IDENTICAL  aluminum tubingtank coil.  Talk about HOT.Nickel ?    You may as well douse it with lighter fluid, and toss in thezippo.Measure the Q of the nickel plated coil vs the copper coil, or silverplated copper coil......and you will be in for a rude awakening.Nickel is worse than phosphor bronze.  I just ran a typ 160m  coil throughK6STI's ' coil'  software....and using copper the Q was 1222.   Withphosphor bronze, it dropped to 464.....and nickel plated is even worse !  (aluminum was a  Q of 857  using 3003-0 alloy).No doubt he wanted nickel so it was weather resistant.I wind my own copper tubing coils....then silver plate em.Jim  VE7RF______________________________________________________________________________________________TowerTalk mailing listTowerTalk at contesting.comhttp://lists.contesting.com/mailman/listinfo/towertalk