BCB
Reject Filter
This design
for an effective Broadcast Band Reject filter came from an
old
commercially made Antenna Multicoupler. I used it in the
Active
Multicoupler I built and it worked well. (See the
KO6BB Multicoupler
elsewhere)
Unlike the usual Low Pass Filter (LPF) this one will pass signals both
below and above the Mediumwave Broadcast Band, allowing Longwave and
Shortwave reception while eliminating Intermodulation problems from
strong Broadcast stations.
The unit should be built in a metal
shielded box and connected between the antenna and
the receiver with 50 Ohm coax cable.
The input/output impedance is 50 Ohms.
COMPONENT VALUES
L1,
L3 12.2uH
L2
4.65uH
C1,
C5 2000pF
C3
6200pF
C4
22pF
Melt
Some Solder!
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