[TowerTalk] Loading Coils

[john at kk9a.com]

I believe the old B&H coils were made from tinned copper.  Isn't that
coating even less conductive than nickel plated?

As far as aluminum coils go, they may not be good for amplifiers but several
big name antenna companies use them on 40m Yagi elements for loading and
they appear to work well.

John KK9A


Jim VE7RF wrote:


##  nickel plated,  He's joking right ?  Years ago, I replaced the silver
plated copper tubing coil in a hb amp with an IDENTICAL  aluminum tubing
tank coil.  Talk about HOT.

Nickel ?    You may as well douse it with lighter fluid, and toss in the
zippo.
Measure the Q of the nickel plated coil vs the copper coil, or silver
plated copper coil......and you will be in for a rude awakening.

Nickel is worse than phosphor bronze.  I just ran a typ 160m  coil through
K6STI's ' coil'  software....and using copper the Q was 1222.   With
phosphor 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