Topband: TRANSFORMER QUESTION

Tom Rauch w8ji at contesting.com
Thu Dec 8 18:54:03 EST 2005


> Anyone tell me what might be going on here?

Typically the 2:1 auto transformers I wind on those cores
have a 1.5:1 VSWR BW up to 30-40 MHz. They are about 1.25 :
1 SWR or less at 15 MHz, and nearly 1.1:1 at 300 kHz.

Did you terminate the transformers when you measured them
Bill, or was this into the antenna?

Were the leads short?

Was it a 7-pass winding around the core window winding loop,
with a tap at the 5th pass? Perhaps the turns ratio is off?

Is it possible you have the wrong mix cores? I've seen the
wrong mix sold by mistake.

73 Tom





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