2 • BX-240
© Box 73 Amateurfunkservice GmbH 2017
For construction, the following tools and
equipment will be required.
– Temperature regulated 60 … 80 W sol-
dering iron with a fine (pencil) tip, 0.5 …
1 mm solder with flux,
– 100 W soldering iron with flat (chisel)
tip,
– Electronics side cutters,
– Flat nose pliers,
– Slot screwdriver,
– Cross head (Phillips) screwdriver.
– Two 1.5 V batteries type AA for power
supply.
Before mounting the board the contents of
the kit should be checked against the parts
list provided.
n
Mounting the board
Fig. 2 shows the layout plan with the few
components still to be soldered.
These are
to be mounted exclusively on the upper
side
where the six pin mounting strip for
the programmable interface is already lo-
cated.
First of all the sliding switch S4 should be
mounted on the face of the board. It should
rest with its underside on the circuit board
with the slider able to move horizontally
Table 1: Technical data
Frequency range 0.1 … 100 MHz
(1 Hz resolution)
Accuracy ≤ 2 % (
f
≤ 50 MHz)
Measurements Complete impedance
values
Measurement range
s
≤ 100,
limits
*
Z
≤ 1000 Ohms
Input 50 Ohms, BNC
Output voltage Peak to peak = 1 V
at 50 Ohms
Power supply 2
¥
1.5 V AA batteries
Current drain 49 mA
**
(110 mA)
Case dimensions 137 mm
¥
90 mm
¥
25 mm (L
¥
W
¥
H)
Weight 290 g, incl. batteries
*
out of limits less accurate results
**
Average value without illumination at
100 MHz and 50 Ohms load resistance, peak
value shown in brackets.
Fig. 1: View of a finished FA -VA4
in a switched off state.
Building instructions
