BX-240 • 3
© Box 73 Amateurfunkservice GmbH 2017
(Fig. 3). The simplest way to do this is to
make a provisional solder connection us-
ing one solder tag on the switch thus al-
lowing for correct alignment whilst heat-
ing the solder. When it is in the correct
position all the connector tags for the
switch along with the two for the housing
may be soldered.
Display
An LED backlit LCD screen is used to dis-
play measured values. These components
are joined together as a single unit and re-
quire partial soldering. To do this, the dis-
play must be placed on the LED backlight
so that there is no gap. All six connections
of the two 3 pin display contacts must be
soldered to the top of the LED backlight
along with the two outside pins of the 20
pin connector strip (Figs. 6 and 7). It is
advisable to use an appropriate support
under the display when soldering to the
LED backlight unit to fix both compo-
nents in the correct position.
The protective film on the display glass
screen should be removed before assem-
bly.
To finish, the three socket assemblies are
fixed to the contact points on the underside
of the display. The upper edge of each
socket must sit flush with the back of the
Fig. 3: Slider switch soldered in correct posi-
tion
Fig. 4: The three plug connectors for display
connection
Fig. 2: FA -VA4 layout plan with soldered parts
