On Sat, 01 Mar 1997 21:52:36 -0700 Jess Gypin <jessqrp@concentric.net>
writes:
>Hi All,
Hi Jess,
> Would it really matter that much if I wound the
>toroids with 24 instead of 26?
No. Bigger than about 18 gauge and you have a problem with
getting all the turns through the core. Smaller than 32 gauge and it's
pretty easy to break the wire (and the Q is a little lower). In between
it will not make a bit of difference. I would use the thicker of the
two you have for purely mechanical considerations- it's stronger.
And contrary to what's been put forth on the list previously,
insulated wire can also be used. The insulation won't make a whit of
difference. Yes, it will lower the inductance per turn by an
infinitisimal amount. Yes, it will change the distributed capacitance by a tiny amount. Neither effect will have any dire consequences. The
larger diameter of the insulated wire will make it tough to get all the
turns on. Finally, Radio shack sells wire-wrap wire. Silver plated
28g (?30) wire with thin teflon insulation- it would do fine. But they also sell enameled (magnet) wire (22,26 & 28, I think 3 spools in a pak).
One more note. You will increase the distributed capacitance
more by getting the beginning of the winding too close to the end of the
winding. So in general you try to have some space between the beginning
and end of the winding, but it doesn't matter all that much. However,
using really large diameter wire will force you to scruntch ALL the
wires together in the middle of the core, including several turns at
both the beginning and the end. That will increase distributed
capacitance more- perhaps enough to actually make a difference when you go to resonate the thing with an external capacitor, although I doubt it.
Someone was bound to mention this; thought I'd pre-empt them. If
anyone has actual data, I'd be curious about the magnitude of that
effect.
73, ; D DWink@Juno.com Dan Winkler N7IVR Seattle, WA
----------whom the gods would destroy, they first make proud ----------
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