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60m filter available

Hans Summers
 


All

Following Andy's design (see pasted below), I have now added a 60m filter to the kit shop?

73 Hans G0UPL
http:/

DESIGN:

Just been playing here with a design for the?60m?band which may be
of use to U2'ers, or Hans if he's requiring a?60m?LPF design.

Take one of the 80m LPF's.

L1 = 23 TURNS (WAS 25)
L2 = 24 TURNS (WAS 27)
L3 = 23 TURNS (WAS 25)

Change C1 and C4 change to 680pf

C2 and C3 remain at 1200pf.

So all you really need in terms of new components are 2 x 680pf caps!

1st harmonic is -58db down
2nd harmonic is -79db down

73 de Andy G0FTD
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