Hans Summers <Hans.Summers@...>
I uploaded my BITX20 pictures into the photographs section
I also re-organised in there a little, so that the photos which were at the
top level are now sorted into directories by callsign.
Some notes on my version:
You will see the first picture has the BITX20 in the foreground and my
80/40m homebrew receiver
http://www.hanssummers.com/radio/polyphase/index.htm in the background. The
frequency counter of the receiver (also homebrew, see
http://www.hanssummers.com/radio/sfreq/index.htm ) is hooked up to the
BITX20 VFO on 4.278.16MHz. You can see the same frequency reading on the
BITX20 readout, i.e. 14.2 from the dial + binary 64 + 8 + 4 + 2 + 0.5 =
The other picture shows 14.175MHz. I fitted an on/off switch, tx/rx switch
and frequency counter on/off switch (in case the counter generates an
objectionable birdie or other noise). A greed LED indicates power is on, the
red LED indicates TX.
I included a photo of my simple 2-chip 8 LED binary readout frequency
counter that I installed in the BITX20 front panel. The details of this
counter can be found at http://www.hanssummers.com/radio/sfreq/index.htm .
It costs approx £2.00 in parts.
I constructed my BITX20 as a series of 15 modules. The VFO is built directly
on the main chassis behind the tuning controls. The remaining modules are
each built "ugly" on a 2 x 1 inch piece of PCB stock, mounted at right
angles to the chassis. This method will allow me to experiment easily with
variations on the different modules. If necessary I could easily move all
the modules around because they are just soldered to the base board at
either end of their 2-inch length. This method also provides for some
"automatic" screening between each stage. All the modules except the product
detector/exciter are shown in the "modules" photo subfolder. Sorry for the
low resolution images of the modules. Some of the main pictures were taken
on a friend's camera. if you have an old unwanted digital camera which is
less old than my 640 x 480 resolution dinosaur, you know where to send it
The rig is now awaiting testing and debugging but due to family commitments
there may be some significant delay.
72/3 de Hans G0UPL