FM Transmitter 4Watt

TECHNICAL CHARACTERISTICS:

stabilized tendency of catering: Vcc=12~16V
Frequency of emission: 88~108MHz
Consumption: 100~400mA


Circuit diagram:




Materially:
The resistors are 1/4W.
R1, R2 10KOhm
R3 47Ohm
C1, C2 1nF
C3 4,7uF/16V
C4, C7, C8 0~45pF trimmer
C5, C6 10pF
C9 100nF
L1 4 turns, 7mm diameter *
L3 3 turns, 7mm diameter *
L4 5 turns, 7mm diameter *
L2 RF choke VK200
T1,  2N2219

T2, 2Ν4427 or MRF 237
ANT Simple dipole l/2.
MIC IN Microphone dynamic or other type. (It can also connected to a cassette player unit)


* The inductors is air from wire of coaxial 75W or other 1mm roughly.
PCB:
Before you print it out with microsoft paints, set the screen resolution to 1280 by 1024 in order to get the correct scale

FM Transmitter 4Watt pcb

Pcb

FM Transmitter 4Watt parts

Components Layout

Regulations:
With the C4 we regulate the frequency.
With their C7, C8 we adapt the resistance of aerial (practically to them we regulate so that it is heard our voice in the radio as long as you become cleaner).
Notes:
The T2 wants refrigerator.


COMBINED WITH

HI-FI Stereo Multiplexer for FM transmitter with NJM2035 I.C. circuit
http://kitaudio.blogspot.com/2012/10/hi-fi-stereo-multiplexer-for-fm.html