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6uH in BITX40 band pass filter? #bitx40

 

Greetings, I'm about to start building a BITX40 with the dead bug style and I've noticed that the filter passes band indicates 6uH however 40 laps on a toroid T30-6 is 5.76uH, not 6 ... I mention this because in my toroids I have 5.8uH and if I give it one more lap I have 6.2uH. So, which one do I use?
 

?A?
ldrich

?I would use 41 turns to start with.? That way you can easily remove one turn if 41 turns
is too much.?

Arv? K7HKL
_._
?


On Thu, May 24, 2018 at 3:04 PM, Aldrich Sarmiento <aldrich.sarmiento@...> wrote:
Greetings, I'm about to start building a BITX40 with the dead bug style and I've noticed that the filter passes band indicates 6uH however 40 laps on a toroid T30-6 is 5.76uH, not 6 ... I mention this because in my toroids I have 5.8uH and if I give it one more lap I have 6.2uH. So, which one do I use?


 

LIke Arv said.? and if its low or high spreading to closing the turns will move the value some.

All you care is the frequency of resonance.? You can tweak the cap soem to make it work.

Allison
 

My doubt is because the same pass filter of BITX40 should not have 6uH because the scheme says 40 turns on toroid T30-6. Apparently this does not affect you. On the other hand I thought it was a filter with a series tuned circuit but if you put 6uH in series with 100pF you get 6.497Mhz ...
Additionally Allison, this filter does not have variable capacitance.
 

The inductor winding (40T) could be tweaked slightly taking turns little closer o to increase 5.76 to become 6uH.
?

please try with little patience you would succeed.

Regards
MVS Sarma
?

On Fri, May 25, 2018 at 4:02 AM, Aldrich Sarmiento <aldrich.sarmiento@...> wrote:
My doubt is because the same pass filter of BITX40 should not have 6uH because the scheme says 40 turns on toroid T30-6. Apparently this does not affect you. On the other hand I thought it was a filter with a series tuned circuit but if you put 6uH in series with 100pF you get 6.497Mhz ...
Additionally Allison, this filter does not have variable capacitance.

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