1. Messages
  2. Twist in a jiffy! Tip for transformers-Use an electric drill

Re: Twist in a jiffy! Tip for transformers-Use an electric drill #50w

Jim Strohm
 

I like Allison's answer best.

Constructing the toroidal inductors as transmission-line transformers (cf. Jerry Sevick (SK)) makes them somewhat more efficient, assuming the circuit is designed for certain input and output impedances.  

Of course, twisting the windings makes adding or removing turns on one winding much more difficult, and compressing or expanding the windings on the core almost impossible.   However, the descriptions of the various woes suggest that the bigger problem is getting enamel off the wires, not the impedance of the completed inductor / transformer.

Sevick's writings tend to support this,

73
Jim N6OTQ 

On Tue, Jun 21, 2022 at 11:08 AM ajparent1/KB1GMX <kb1gmx@...> wrote:
As someone that was involved with racing and aircraft ownership
I still have my safety wire pliers.  Also a small hand cranked
manual drill.

FYI: two many twists tends to make the wires brittle and I found
around 8 twists is easy to work with.  Two few makes it loose and
looks poor once on the core.  The majik number has a wide
variation as I did it as parallel pairs and triples.  That looks
pretty when using tricolor wire and buys nothing.  So there is a 
fair amount of latitude.   Also wide variations tends to only show
at increasing frequencies (greater than 20mhz).


Allison
-------------------------------
Please reply on list so we can share.
No private email, it goes to a bit bucket due to address harvesting

Join QRPLabs@groups.io to automatically receive all group messages.