Re: ubitx LPF #bitx20help #bitx40help #ubitx #bitx40 #ubitx-help

hickmodawg@...
 

Why not use the online calculators to get an estimate of the number of turns we need, and then use an inexpensive meter to fine-tune the number and arrangement of windings before installing the toroid on the board?  I got a cheap LC100-A meter on EBay that measures inductance and I was a little shocked to see how the inductance values of my toroids changed just from moving the windings closer or farther apart, not just from adding or subtracting winds.  It seems to me, that the size and composition of the toroid, and the spacing of the windings may have an effect on the resulting inductance, not just the number of windings.  I’m really still quite new to this, but, I’m wondering, why not use a meter before installing our toroids onto the board?  Is it because these cheap meters are very inaccurate?
Martin, AJ6CL

Join BITX20@groups.io to automatically receive all group messages.