Hi Chris and Julius,
In the experiments with 9MHz filter the crystals turned out to be
about 9.015MHz. With the BFO exactly on 9.005 MHz I get both sides of
the filter and I can determine the centerfrequency of the filter. I
put a picture in the Photo-box (PE2BS). The red one is without
matching impedance, the green one after matching. The filter is not
ready so it's just an exemple of the use of SpectrumAnalyzer.
73
Ruud (PE2BS)
--- In BITX20@..., "vdberghak" <vdberghak@z...> wrote:
Hi Julius,
that is the fun, nothing to adjust in advance, just connect it (I
used two resistors as a signal attunuator)and watch the screen (if
you receive enough noise).
If you do not receive enough noise, you can choose that the peak is
hold, slowly tune over a carrier (can be anything, no requirements
about stability or so)and see the graph.
In fact, using this tool makes it easy to see if the BFO frequency
is correct. If you just click the link in 'Links, software' or
click
on you can see many samples
and an easy explenation.
(If you do not want to connect it and first want to see how it
works, you can use your microphone and hold it in front of the
speaker).
Please keep us informed about the results.
Thanks in advance,
Chris.
--- In BITX20@..., "Wijaya, J." <iyung_w@y...> wrote:
With the software and connecting the output of the AF amp to PC,
i wonder where do we set the BFO to find out the shape of our
filter, assuming that we do not know the center frequency yet, or
setting the BFO is not necessary?
rgds
julius
