Symasym5, is a "cute" power amplifier, designed with quality but still low price in mind. This resulted in a ClassAB BJT amplifier, using only TO92 transistors for input and VAS, with a reasonable part count. The topology used is well known and consist of a single diffamp for input, plus a 2nd diffamp with current mirror for VAS. This is followed by normal darlington EF outputstage using modern high beta devices. The circuit uses large amounts of feedback over the whole audioband and an unconventional feedback compensation scheme. Right now symasym is designed to be driven directly from a CD/DVD-player, simply place a 22k poslog stereo pot between player and symasym. (as voltage divider)Update
The at least change is to reduce C14 from 22pF to 10pF, but i recommend to follow Pavel's advice.
I recommend C14 with 10pF also for MJLs, this increases safety margin.
Do not forget to read Pavel's Review! A very promising evaluation of the qualities to be expected from symasym. Thanks Pavel !
Another update are the resistors R31/32 to be increased from 22ohm to 47ohm. Symasym5_3 is an update of v5.2, with an improved board layout concerning power gnd,
Actrk 400/600 Watt
Two versions of a robust module capable of delivering high powwer for extended periods. The Actrk400 uses 6 n-channel Mosfets in the output stage to deliver around 400 watts into 4 ohms while the Actrk600 uses 12 n-channel Mosfets in the output stage to deliver power in excess of 600 watts into 4 ohms. One constructor has achieved almost 900 watts with the Actrk600 layout using 12 IRFP460 Mosfets.
Actrk 600W schematic
The TA7222 is a power amplifier for consumer application.
It is designed for high power, low distortion and low noise.
It also contains various kind of protectors.
It is suitable for car – audio power amplifier with high performance.
Operating Supply Voltage Range Vcc = 9~18volt
High power is 6Watt
COMPONENTS LIST
Resistors:
P1=100kΩ
R1=27 kΩ
R2=220Ω
Capacitors:
C1=4,7μF/50V
C2=470μF/22V
C3=47μF/22V
C4=100nF
C5=47μF/22V
C5=470μF/22V
Semiconductors:
IC1= TA7222AP
Miscellaneous:
Heatsink for IC1
PT2350 is a tone control subwoofer cross-over low pass filter chip utilizing CMOS Technology. It features a tone control range of + 10dB (50Hz, 4 KHz) and subwoofer low pass filter of the second order Sallen Key Design. The roll-off point can be adjusted by changing the value of the external capacitor. Pin assignments and application circuits are optimized for easy PCB Layout and cost saving advantages.
CMOS Technology
2-Channel Input
3-Channel Output (Including 1 stereo Output and Subwoofer Output)
Low Total Harmonic Distortion (THD<0.01%, Subwoofer THD<0.2%)
High S/N Ratio (S/N Ratio <-87dB, A-weighting)
Least External Components
Adjustment of Frequency response by changing the value of the external component
Single Power Supply: 3 to 8.5 Volts
Available in 20 pins, DIP or SO Package
PARTS
Resistors
2------ R1,R2-------------- --------- 10k / 1% / metal film
Capacitors
2------ C9,C10------------- -------- 4.7nF / 63V / polyester / raster R. 5mm
3------ C1,C7,C8-------- ----------- 47nF / 63V / polyester / raster R. 5mm
1------ C16---------------- --------- 100nF / 63V / polyester / raster R. 5mm
1------ C13----------------- -------- 220nF / 63V / polyester / raster R. 5mm
2------ C3,C4------------- --------- 2.2uF / 50V / polyester / raster R. 5mm
5------ C5,C6,C11,C14,C15--- 3.3uF / 100V / electrolytic / vertical / raster R. 5mm
1------ C12-------------------------- 10uF / 35V / 105°C / electrolytic / vertical / raster R. 5mm
1------ C17----------------- --------- 100uF / 16V / 105°C / electrolytic / vertical / raster R. 5mm
1------ C2---------------------------- 470uF / 35V / electrolytic / vertical / raster R. 5mm
Integrated Circuits
1------ U1---------------------------- 78L08 / +8V voltage regulator / TO-92
1-------U2---------------------------- PT2350 / stereo tone control, subwoofer low pass filter IC / DIP20
Diodes
1------ D1---------------------------- 1N4153
Miscellaneous
1------ J1----------------------------- 2 pole wire connector (terminal block) to pcb / raster r. 5 mm 9.7 mm
1------ P1----------------- ----------- 10k log stereo potentiometer / 6 mm
2------ P2,P3------------------------ 100k lin stereo potentiometer / 6 mm
5------ J2 to J5---------------------- RCA female to PCB, straight, Hosiden any colour
!!! NOTICE ABOUT J2 to J18 !!! if you make one stereo input device you need 5 pcs of RCA female as listed in parts list
If you make 2 x 6 input device, you need total quantity of 15 pcs RCA female and also 2 x 6 changeover switch.
Code of J2 to J18 RCA female to PCB, straight, Hosiden, any colour
SW1 2 x 6 changeover High quality DIP rotary switch to PCB 2 x 6, Alcos witch DRS 2-6, 3.2mm saft
Frequency response of tone control unit is flat between 20 Hz … 20 kHz when treble and bass pots are in middle.
Overall gain is approx. 6 dB when treble and bass pots are in middle.
Treble and bass tone control range is approx. 10 dB (50Hz / 4 kHz) with given component values.
Subwoofer cut off frequency can be adjusted by bass potentiometer… with component values as listed above it is as follows : bass pot in minimum (left) -3dB point, 240 Hz / -12dB 450 Hz, bass pot (middle) -3dB point 100 Hz /-12dB 200 Hz, bass pot maximum (right) -3dB point 60 Hz / -12dB 120 Hz.
Distortion was < 0.1 % when input level was < 0.3V rms.
There is no balance adjustment potentiometer in this application, if you need balance, you must add it separately in this device.
Output Power : 200Watts
Load Resistance : 8ohms
Input impedance : 55K
Maximum supply voltage : (+95v)-0-(-95v)
Recommended supply voltage : (+66v)-0-(-66v)
This complete high quality, low noise mono audio power amplifier is based around the Hybrid Integrated Circuit STK4050 manufactured by Sanyo. The circuit incorporates volume and has a maximum music output power of 200W. The circuit incorporates an on board power supply; therefore, only centre tapped transformer is required to power the circuit. I t has very good quality sound. U can use it with your Home Theatre your PC & etc... You can also use it as Subwoofer Amplifier. It is a compact package for THIN-TYPE Audio sets. Easy Heat sink design to disperse heat generated in THIN-TYPE audio sets. Constant-Current circuit to Reduce supply switch-ON and switch-OFF shock noise. External supply switch-On and switch-OFF shock noise muting, Load short-circuit protection, thermal shutdown and other circuits can be tailored-designed.
TECHNICAL CHARACTERISTICS:
Stabilised tendency of catering: Vcc=12~16V
Frequency of emission: 88~108MHz
Consumption: 100~400mA
Stabilised 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 RFC (resistance 1MOhm with wrapped around her inductor of enough coils from fine isolated wire. Scratch of utmost inductor and you stick in utmost the resistance making thus a parallel L-r circuit.)
T1, T2 2N2219
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.
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 RFC (resistance 1MOhm with wrapped around her inductor of enough coils from fine isolated wire. Scratch of utmost inductor and you stick in utmost the resistance making thus a parallel L-r circuit.)
T1, T2 2N2219
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 by1024 in order to get the correct scale
Before you print it out with microsoft paints, set the screen resolution to 1280 by
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).
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.
The T2 wants refrigerator.
