[Elecraft] Tolerances of RF Chokes K2 (6291)

[Vic K2VCO]

edwin.ebert wrote:
> Hello 
> I am building up a K2 with great pleasure.
> Now I have wound the RFC 14 und 16. If I measure the Inductance with an AADE
> (and compare with a second instrument) I get 29 uH for the RFC14 and 78uH
> for the RFC 16. In the Manual are the values 18uH (RFC14) and 47uH (RFC16).
> The deviation is about 50-60%.
> (The number of turns are correct and spread out to 90% of the toroid)
> 
> My question: Why is this difference so big? Is this the tolerance of AL?
> Is it correct that this differences are not crucial for the purpose of this
> rf chokes?

The inductance of a coil wound on a toroid core depends on the frequency 
of measurement, because of the properties of the core material. I don't 
know what frequency the AADE meter uses, but it may not be the same as 
the frequency at which the chokes are spec'd. If the chokes are wound 
properly on the correct cores, they will work properly.
-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco