Topband: Binocular Xfrmr Follow-Up

Mike(W5UC) & Kathy(K5MWH) w5uc at
Fri Oct 19 08:25:52 EDT 2007

Good Morning All:

First, my sincere thanks to the many who responded to my 
dilemma.  Your generous outpouring of information was interesting and 
educational. The most interesting part of it is that you confirmed 
that I had built the xfrmr correctly. With such a tremendous amount 
of information leaning in that direction, yesterday I built a new 
xfrmr on a standard 43 Mix core, and replaced the binocular 
core.  There wasn't much to work with on the band last night, but 
with what there was, I determined that things were back to normal. Success.

THEN, with the supporting data from so many of you, I did an autopsy 
on the binocular core xfrmr. I am surprised, and somewhat embarrassed 
with what I found. I had used some relatively new enameled wire for 
the 3 turn low-Z winding. Then, I used wire from another spool for 
the hi-Z winding because it is a different color. That spool is one 
that I have had for a great many years, and appears to have been my 
undoing. The low-Z wire was the inner winding, but was clean & slick 
when removed, but the hi-Z winding was rough as if it were all 
scratched up. I haven't been able to determine visually if the 
coating is gone in the rough spots, but everything leans in that 
direction. Apparently the enamel has deteriorated to beyond it's 
useful life. I guess that's the price I pay for being a pack rat.

I will rebuild the xfrmr using the same core, but all new wire. 
Again, thanks for all the inputs. Stand by for news.

Mike, W5UC

"age & treachery will overcome youth & skill" 

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