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An FM transmitter display

2016-04-08 00:00  
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Then there is a frequency modulation transmitter. Although there are a lot of similar transistor 2 charts are available, this is higher than the average. A major improvement small 1 transistor circuit, we have discussed before, the transmitter consists of two stages. The first transistor is used for audio amplification, which means that the more sensitive microphone sound now. The second ACTS as a generator. Understand the principle diagram has a few things to note:
1. Native language and foreign language is 5 turns 28 AWG magnet wire wound enamel coating and 4 mm inner diameter. Atoms within the written test (plastic pipe can put the ink). And then install the coil in the delete form completion of the circuit board, be careful not to bend.
2. The C5 is used for tuning. The transmitter operating normal radio frequency (88-108 MHZ).
3. Q1 and Q2 can be  2 n3904  or something similar.
4. You can use a quarter W resistor installed vertically, rather than 1/8 W resistor.
5. You may want to bypass the battery. 01 uf capacitor.
6. An antenna may not need operations.
Read a few times more the principle chart will help you to better grasp the principle. The circuit is simple but very useful.

Schematic

This is the schematic of the FM Transmitter

PC board layout and parts placement

This is the printed circuit layout and parts placement of the  FM Transmitter

Parts:

PartTotal Qty.DescriptionSubstitutions
C110.001uf Disc Capacitor 
C215.6pf Disc Capacitor 
C3,C4210uf Electrolytic Capacitor 
C513-18pf Adjustable Cap 
R11270 Ohm 1/8W Resistor270 Ohm 1/4W Resistor
R2,R5,R634.7k 1/8W Resistor4.7K 1/4W Resistor
R3110k 1/8W Resistor10K 1/4W Resistor
R41100k 1/8W Resistor100K 1/4W Resistor
Q1, Q222N2222A NPN Transistor2N3904
L1, L225 Turn Air Core Coil 
MIC1Electret Microphone 
MISC19V Battery Snap, PC Board, Wire For Antenna 

 

 

 


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