Another feature of the Ubitx which is
not usually found in low power radios is the
comprehensive and well-conceived operator
interface. Ubitx operators can access a host of
menu options simply by depressing the tuning
encoder. These options include a receive
incremental tuning (RIT), dual variable frequency
oscillators, a CW keyer, calibration, and many
others. Most of the menu options have logical
defaults which are easily overridden.
To enter CW mode from single side-band
mode, the operator need only press his CW key.
The Raduino will return to SSB mode when it
senses that the operator has stopped keying.
The Ubitx kit comes with a completely built
and tested main board, Raduino, and all the
peripherals and parts. It doesn’t include a speaker, a
power supply, or an enclosure.
Building the Transceiver
Instructions for building the Ubitx transceiver
are found on
Hfsigs.com. A note to new builders:
The Ubitx build does require soldering. Some prior
experience with kit building and schematic reading
will be very helpful. Ubitx can be assembled by
following the wiring diagrams shown in Figures
9. Or, if the builder prefers, Farhan has placed
more detailed instructions on
As you build Ubitx, be very
careful that the main board
doesn’t get exposed to static
electricity. Even the smallest
charge of static electricity can
destroy a board’s circuitry.
Included with the kit is a
1N4007 diode which is to be
connected across the power
connector to prevent damage
from short circuits and other
spikes in power. Unfortunately,
the 1N4007 diode doesn’t
provide adequate protection.
Every builder should place
a two-amp fast blow fuse in
the positive line of the power
supply. It’s much better to take
the time to add a fuse than to
8. Farhan’s wiring diagram for the Microbitx.
9. Another wiring diagram
for the Microbitx from
September/October 2018 65