Hi Juanjo,
Which band are you designing it for? 4.915 is too low for 14MHz
SSB and sets
the VFO tuning quite high and prone to QSY/QRH (drifting). As I
have read
over there, for SSB IFs over 8MHz are better and set the VFO on
lower and
more stable frequencies.
There are more reasons for making the filter in the range 10 to 12
MHz, one for example is that lower IF x-tal ladder filters are
difficult for SSB, for CW they seems to be great.
My BITX will be for the 18 MHz band so my LO will be in the 13 MHz.
I will try a VXO, covering the whole phone band.
Crystals between 8 and 12MHz are easy to get here
in Europe,
They are also cheap available by one of the group members but (as
mentioned by one of the other group members) some persons have a
kind of brain damage that force us to use what we have. Spending
hours to get some used parts from an old PCB cost ofcourse more then
buying new but now I can say: 'I build this transceiver from scrap
and components that I had collected in the past'.
An other point of view; by using these alternatives, you learn a lot
about parameters and the circuit!
(If I do not get it working the way I want to, may be I will go to
the 10 MHz IF ;-) ).
I am not building the BITX, but I am enjoying this list and
learning about
I appreciate your comments, as mentioned above, search in your junk
box and build your own tranceiver based on the BITX20.
Chris, PA3CRX
