Hi all,
I am building the Bitx40 dead bug style. Basically changing the Bitx20 and using a different BPF, VFO frequency and low pass filter. For the BPF I used the design shown on the hfsigs website. Instead of T30-6 I used three T37-6 I had lying around, added 5 extra turns (45 in total) on each toroid which came to 6 uH as well. It turns out the signal peaks at around 7.550 MHz which is too high in frequency.?
What would be the best way to lower the center frequency of this filter? I have the toroids covered in glue so if it is possible by addjusting the capacitor values only. If the filter becomes wider that would not be a problem at all. I use an IF of 10 MHz and a VFO of 17 so there will not be many harmonics in the 40 meter band.
I would appreciate it if someone can point me in the right direction.
Thanks, PH0KKO
