I used a dip meter to roughly adjust the individual LC's to the
correct frequency.
Then I connected them together and peaked them.
May be adding the capacitor on one coil, did change also the
resonance frequency of the other resulting in zero throughput?
I would suggest to listen to a signel in the band and then tune the
trimmers to maximum sound.
Good luck,
Chris.
--- In BITX20@..., "David WardenDurkee" <dwarden2@c...>
wrote:
I am adjusting the receive BPF using a sine wave generator and
oscilloscope.
The first of the three sections peaks at about 14.2 Mhz, but the
second peaks at 16 Mhz.
I tried to add 12 pF additional capacitance to lower the resonant
frequency, but the sine wave disappears completely.
Is my problem mutual inductance canceling the 14.2 Mhz signal?
Any ideas or help is appreciated.
Thanks,
Dave
