YouKits TJ2B, Construction Manual

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PTT - Push to talk. Press to transmit.
DC12V - External power socket
5. Miscellaneous
Bias resistor R62 - This resistor depends on the specific power transistor and D18.
The
supplied resistor is 680 ohms
.
LCD Holder - Sink the 2 mounting screws (screen side) as deep as possible. Otherwise
the LCD could not reach the position. If necessary, taper the 2 mounting holes a little so
that the screw heads sink a little. Use a knife or a drill bead to taper, i.e., to tim the eadge
of the mounting hole
.
The material is rather soft.
BFO calibration - There is the possibility that the BFO frequency cannot be adjusted to
8.99840MHz. The highest is 8.9980MHz. Never mind. Use 8.9980MHz as LSB. In this
case, USB frequency should be 400Hz lower, i.e., 9.0008MHz (USB is 2.8kHz apart from
LSB), not 9.0012MHz. Also, the alteration should be made in IFS in the DDS calibration
procedure. IFS should be set to "-2000", instead of "-1600".
EXT PWR Socket - This socket makes pushing-in-the-main board a little difficult, not the
two 220uF caps. However, if correct procedure is followed, pushing in the main board
would be very easy. Try to push the socket inwards when soldering it to the PCB so that it
moves back a little instead of projecting.