60
Circuit 35:
LM antenna amplifier for antennas with short wires
Setup information
Install the two transistors and the four resistors as shown in
Fig. 2.35.
Then install the three ceramic capaci-
tors. The six jumper wires come next. Check the placement on the board again and only then connect the
battery. Connect the circuit input to a short-wire antenna. The output is connected to the antenna input of
an LW – MW radio receiver – but only if you are familiar with the relevant safety guidelines on working with
devices that are to be connected to the mains as per VDE and know how to observe them
Components required:
1 x 2N3904 transistor,
1 x J111 FET transistor,
1 x 1 M
Ω
resistor,
1 x 56 k
Ω
resistor,
1 x 6.8 k
Ω
resistor,
1 x 470
Ω
resistor,
2 x 100 nF ceramic capaci-
tors, 1 x 10 nF ceramic
capacitor, 1 x breadboard,
1 x 9V battery with clip
connector
Fig. 2.35:
LM antenna amplifier
for antennas with short wires
Experiment
If everything is wired correctly, the circuit will amplify the low receiving voltage of the wire antenna in LW
and MW ranges. You should be able to receive several remote stations during the day in addition to the
local station on medium wave. Despite or better due to the complex IP radio and DAB+ systems, the uncom-
plicated and genuinely mobile MW reception seems to be experiencing some sort of comeback.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.35.
Summary of Contents for ELECTRONICS EXPERIMENTS BOX
Page 4: ......
Page 265: ...267 Fig 3 56 Cir cuit 56 Audio limiter Fig 3 57 Circuit 57 Amplifier for a storm detector...
Page 269: ...271 Fig 3 64 Circuit 64 Stabilizer for 1 9 V Fig 3 65 Circuit 65 Stabilizer for 2 5 V...
Page 275: ...277 Fig 3 80 Circuit 80 Quiztimer 30 seconds Fig 3 81 Circuit 81 Handy diode tester...
Page 315: ...317 Fig 3 179 Circuit 179 HF generator 150 kHz Fig 3 180 Circuit 180 HF generator 420 kHz...
