nadajnik 400mW

Technické údaje

Napájení: 12-14 V stabilizované, 100 mA
Vf výkon: 400 mW
Impedance: 50-75 ohmů
Frekvence: 87,5-108 MHz
Modulace: FM širokopásmová

Schéma zapojení

Seznam součástek

Kondenzátory:

C1, C2, C12 - 100 pF keramický
C3, C5 - 0,22 uF elektrolytický
C4 - 1,8 nF keramický
C7, C18 - 100 nF mini keramický
C8, C9 - 10 pF keramický
C10 - 47 pF keramický
C11 - 8,2 pF keramický
C13, C16, C17, C19 - 1 nF keramický
C14 - trimr 60 pF
C15 - trimr 35 pF
C20 - 470 uF
D1 - BB409, KB109G, BB109G, BBY31
T1 - BC547C (BC548C, BC547B)
T2 - BFR91A (BFR96)
T3 - BFR96

  Parts:

1x BH1417 - Stereo PLL Transmitter IC (Case SOP22)
1x 7.68 MHz Crystal
1x MPSA13 - NPN Darlington Transistor
1x 2.5 Turns Variable Coil
1x MV2109 - Varicap Diode
1x 4-DIP Switch
ANT - 30 cm of copper wire

1x 22K Resistor
7x 10K Resistor
1x 5.1K Resistor
2x 3.3K Resistor
1x 100 Ohm Resistor

1x 100uF Capacitor
3x 10uF Capacitor
2x 1uF Capacitor

1x 47nF Capacitor
3x 2.2nF Capacitor
1x 1nF Capacitor
1x 330pF Capacitor
2x 150pF Capacitor
1x 33pF Capacitor
2x 27pF Capacitor
1x 22pF Capacitor
2x 10pF Capacitor

  Technical Specifications:

Supply Voltage: 4 - 6V
Transmission Frequency: 87.7 - 88.9MHz, 106.7 - 107.9MHz (200kHz steps)
Output RF Power: 20mW
Audio Frequency: 20 - 15KHz
Separation: 40dB
Power Consumption: 30mA

NADAJNIK UKF

schemat druku:

 

Be sure to observe correct polarity of the varicap, transistors and the electrolytic capacitors. Also don't forget to place the two ferrite beads on the leads of R8 and R11. These are needed to cut some of the harmonics and RF noises, thus making the unit more stable.

 

These are the parts needed for the unit: 

Capacitors:

They can be of any size, although smaller ones are recommended

C1 - 4,7 Mf

C2, C3, C13, C16, C21 - 1 nF

C4 - 33 pF or 30pF

C5 - 20 pF trimmer (or more)

C6 - 47 pF

C7, C20 - 22 pF

C8, C9, C15 - 100 pF

C10, C12 - 0,22 mF (=220 nF) electrolytic

C11 - 1,8 nF or 2,2nF

C14 - 100nf

C17, C18, C19 - 40 pF trimmer (or more)

C22 - 470 mF (16 volts or more, not critical) electrolytic

 

Resistors:

No more than 0,5 watts of power. Recommended - 0,25W (as small - as better)

R1, R5 - 10 k

R2, R8 - 470

R3 - 100

R4, R6 - 27 k

R7 - 220

R9 - 47

R10 - 22 k

R11 - 10

P1, P2 - 10k variable

 

Coils:

All coils are air-core types, 6mm internal diameter, wound of 0,7 mm copper wire. Make sure their turns are not touching each other.

L1, L6 - 3,5 turns

L2 - 2,5 turns

L3 - 1,5 turns

L4 - 9,5 turns

L5 - 4,5 turns

L7 - 6,5 turns around the R3 resistor

 

Semiconductors:

D1 - BB409 or BB109 varicap

T1 - BF199 plastic (half-moon)

T2 - BFR91 plastic (small black cylinder)

T3 - BFR96 plastic (small black cylinder)

T4 - 2SC1971

 

przenosny nadajnik FM - bezcewkowy !!! 

the circuit diagram of a versatile FM transmitter that doesn't have a coil. The circuit is simple and easy to assemble.

The gate N1 acts as a buffer for strengthening the signals from the condenser microphone. The inverter N2 with its  associated components forms a radio frequency oscillator in the FM region.The varicap diode  BB109 is used for frequency modulating the audio signal to the carrier wave generated by the oscillator.Inverters N4 t0 N6 are used to drive the antenna.As the N4,N5,N6 are connected in parallel their effective output impedance is very less and can easily drive the antenna.

Circuit diagram with  Parts list. 

Notes. 

• All electrolytic capacitors must be rated 10V.

• Use any general purpose condenser microphone.You can easily get one from old telephone or tape recorder.

• Use a 10 cm long wire as antenna.

• Gates N1 to N6 belong to same IC CD4069.

• The battery can be a 9V transistor radio battery.Adapters are not recommended because they would induce noise in the circuit

---