Showing posts with label mini. Show all posts
Showing posts with label mini. Show all posts
Wednesday, October 15, 2014
4 X 15 Watt Mini Power Amplifier
A lot of electronic circuits in the domain of audio amplifiers are already been published here. This circuit is a little different because it is a four channel amplifier. Each channel of this amplifier can deliver an output of 15Watts into a 4 ohm speaker. The amplifier can be operated from a single 12V DC supply and this makes it possible to use this amplifier in car audio applications too.
Circuit diagram :
4 X 15 Watt Mini Power Amplifier
The circuit is based on the 15W BTL X 2 channel audio power amplifier IC TA8215 from Toshiba. Even though chip is specifically designed for car audio applications it can be also used for home audio applications. Two TA8215 ICs are used here in order to obtain a 4 channel amplifier system. The circuit is designed almost exactly as per the application diagram in the ICs datasheet. Pins 7 and 19 are the Vcc pins of the ICs internal integrated power amplifier stages and these pins are connected to the positive supply. Pin 9 is the Vcc pin for ICs internal preamplifier and it is also connected to the positive supply. Pins 13 and 14 are the internal power amplifiers ground pins and they are tied together and connected to the ground.
The internal preamplifier’s ground pin (pin5) is connected to the common ground through a 10 Ohm resistor which makes the input ground separated from the common ground by a resistance of 10 ohms and this improves the noise rejection. The 100uF capacitor works as a power supply de-coupler. The resistor networks connected to the output lines of each amplifier improves the high frequency stability. The variable resistors (R3, R4, R12 and R13) works as the volume controller for the corresponding channels.
Notes :
- Assembling the circuit on a good quality PCB is a must for obtaining optimum sound quality.
- Use 12V DC for powering the circuit.
- The ICs must be fitted with adequately sized heat sinks.
- R3, R4, R12 and R13 serves as volume controllers.
- K1 to K4 can be 4 Ohm, 20W speakers.
- This amplifier circuit can be used in a variety of applications such as car audio systems, home theater systems, personal audio systems, public address systems etc.
Wednesday, August 20, 2014
Mini FM Transmitter
Here the schematic diagram of mini and simple fm transmitter.
Supply voltage : 1.1 - 3 Volts
Power consumption : 1.8 mA at 1.5 Volts
Range : 30 meters max. at 1.5 Volts
Here the PCB Layout:
Read More..
Supply voltage : 1.1 - 3 Volts
Power consumption : 1.8 mA at 1.5 Volts
Range : 30 meters max. at 1.5 Volts
Here the PCB Layout:
Visit this page for complete explanation
Thursday, August 14, 2014
9V Mini FM Transmitter
The following diagram is the schema diagram of 9V Mini FM Transmitter.
Schematic diagram:
Components List:
R1,R3 = 100K
R2 = 10K
R4 = 470 ohm
C1,C4 = 470pF
C2,C3 = 4.7µF/16V
C5,C6 = 4.7pF
C7 = 4-40pF trimmer cap (optional, see text)
L1 = 1µH
Q1,Q2 = 2N2222, NPN transistor
Mic = Electret Microphone
B1 = 9 Volt battery
Circuit Notes:
Absolutely nothing crucial here. To get a bit of tuning out of the coil you could put a 4-40pF trimmer capacitor (optional) parallel over the 1 µH coil, L1.
C1/C4 and C5/C6 are ceramic capacitors, preferably NPO (low noise) types. C2/C3 are electrolytic or can be tantalum kinds.
In the event you determine to substitute transistors with some thing similar you already have, it perhaps necessary adjust the collector voltage of Q1 by changing the value of R2 or R3 (simply because you alter transistors, it changes this bias on the base of Q1). It ought to be about 1/2 the supply voltage (about four or 5v).
The antenna is nothing more than a piece of 12" wire or a piece of piano wire from 6" to 12".
To find the signal on your regular FM Radio dial, make certain theres a signal coming into the microphone, otherwise the schema will not function. I use an old mechanical alarm clock (you know, with those two big bells on it). I put this clock by the microphone which picks up the loud tick-tock. Im certain you get the concept... Or you can just lightly tap the microphone whilst looking for the location of the signal on your receiver.
The antenna is nothing more than a piece of 12" wire or a piece of piano wire from 6" to 12".
To find the signal on your standard FM Radio dial, make sure there is a signal coming into the microphone, otherwise the schema wont work. I use an old mechanical alarm clock (you know, with those two large bells on it). I put this clock by the microphone which picks up the loud tick-tock. Im sure you get the idea... Or you can just lightly tap the microphone while searching for the location of the signal on your receiver.
Source: http://www.sentex.ca/~mec1995/circ/fmt4.html
Design by Tony van Roon
Read More..
Schematic diagram:
Components List:
R1,R3 = 100K
R2 = 10K
R4 = 470 ohm
C1,C4 = 470pF
C2,C3 = 4.7µF/16V
C5,C6 = 4.7pF
C7 = 4-40pF trimmer cap (optional, see text)
L1 = 1µH
Q1,Q2 = 2N2222, NPN transistor
Mic = Electret Microphone
B1 = 9 Volt battery
Circuit Notes:
Absolutely nothing crucial here. To get a bit of tuning out of the coil you could put a 4-40pF trimmer capacitor (optional) parallel over the 1 µH coil, L1.
C1/C4 and C5/C6 are ceramic capacitors, preferably NPO (low noise) types. C2/C3 are electrolytic or can be tantalum kinds.
In the event you determine to substitute transistors with some thing similar you already have, it perhaps necessary adjust the collector voltage of Q1 by changing the value of R2 or R3 (simply because you alter transistors, it changes this bias on the base of Q1). It ought to be about 1/2 the supply voltage (about four or 5v).
The antenna is nothing more than a piece of 12" wire or a piece of piano wire from 6" to 12".
To find the signal on your regular FM Radio dial, make certain theres a signal coming into the microphone, otherwise the schema will not function. I use an old mechanical alarm clock (you know, with those two big bells on it). I put this clock by the microphone which picks up the loud tick-tock. Im certain you get the concept... Or you can just lightly tap the microphone whilst looking for the location of the signal on your receiver.
The antenna is nothing more than a piece of 12" wire or a piece of piano wire from 6" to 12".
To find the signal on your standard FM Radio dial, make sure there is a signal coming into the microphone, otherwise the schema wont work. I use an old mechanical alarm clock (you know, with those two large bells on it). I put this clock by the microphone which picks up the loud tick-tock. Im sure you get the idea... Or you can just lightly tap the microphone while searching for the location of the signal on your receiver.
Source: http://www.sentex.ca/~mec1995/circ/fmt4.html
Design by Tony van Roon
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