A source of ceramic forms for winding the chokes is to use the body of an
old high wattage ceramic resistor (~100w). Remove the resistance wire and
you end up with a ceramic form. The operative word is "old".
WWII vintage resistors are good as the outer covering just flakes off when
unrolling the resistance wire leaving a relatively smooth ceramic body. If
you mount the ceramic form on a stand off insullator, the tabs the
resistance wire was connected to can be used to tie off the beginning and
end of the choke winding. (Small ceramic stand-offs are easier to find than
large ceramic forms.)
I've wondered why the resistance wire couldn't remain and not hook the choke
winding to the tabs, or disconnect the resistance wire from the tabs if the
tabs are to be used to anchor the beginning and ending of the choke winding?
Haven't tried it, but can't think of a reason why the resistance wire
couldn't stay on the form. Thoughts from the group.
73,
Mike, K4GMH
At 03:54 PM 10/27/98 -0600, you wrote:
>
>>Now, how do you folks who wind your own accomplish getting the windings to
>>stay where you want. Do you paint them with coil dope before removing the
>>spacing wind? This is my first attempt and I need a little Elmering...
>
>Carl, KM1H, once suggested using a little fingernail polish. I tried
>this on some coils I wound and it works GREAT.
>
>Just put a dab on the wire shortly before where you are going to apply
>the spacing.
>
>However, if you are using a spacing wind, I am guessing that you are
>creating a multi-section choke with supposedly different values of
>inductance per each section. Well, according to some of the Elmers here
>on the list, these sorts of chokes suffer from worse resonances than just
>straight wound, single section chokes. What happens is that the choke
>sections tend to couple to each other.
>
>Try the fingernail polish stuff to hold it though, it works good.
>
>73,
>
>Jon
>KE9NA
>
>
>--------------------------------------------------------------------------
>Jon Ogden
>
>jono@enteract.com
>www.qsl.net/ke9na
>
>"A life lived in fear is a life half lived."
>
>
>--
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>
>
>
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