nice work.You could replace your 2 x 47pF ceramic capacitors with something better like silver mica or multilayer.
Can BD249C be used as output transistors?
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is this amply same as bellow
Hi apexaudio your AX6 quit similar to following please give feedback
Motional feed back amplifier - Electronic Circuits and Diagram-Electronics Projects and Design
Hi apexaudio your AX6 quit similar to following please give feedback
Motional feed back amplifier - Electronic Circuits and Diagram-Electronics Projects and Design
Hi, what's the output power with 50Vcc power supply?...I'm building a similar amplifier, with sigle power supply....thanks
Help on AMP
Hello Wiljj78
Can I used 2n3055 instead 2n3773 and bd 139 instead MJE340 any other changes in circuit have to make to work with following supply. I have 22 0 22 AC 1.2A transformer. can it works and how many watts in 8ohm load with this supply.
Hello Wiljj78
Can I used 2n3055 instead 2n3773 and bd 139 instead MJE340 any other changes in circuit have to make to work with following supply. I have 22 0 22 AC 1.2A transformer. can it works and how many watts in 8ohm load with this supply.
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22-0-22Vac gets you to a supply voltage that will allow approximately 28Vpk to 30Vpk into your speaker.
That determines the maximum output power, if you allow sufficient current to flow to the load.
That determines the maximum output power, if you allow sufficient current to flow to the load.
1.2A is a pretty small transformer - It will probably drop from +/-30V all the way to +/-22V under load (about 25 watts RMS). That will make it a bit safer to use 3055's.
When a transformer is loaded that heavily, the leakage reactance will drop the DC down from the peak voltage to the average, which is close to the RMS. And that's even before considering resistive losses. Many a cheap stereo was built this way - especially from the era from where this circuit came.
When a transformer is loaded that heavily, the leakage reactance will drop the DC down from the peak voltage to the average, which is close to the RMS. And that's even before considering resistive losses. Many a cheap stereo was built this way - especially from the era from where this circuit came.
Is the 0.22R resistor for filtering together with the output cap or is it needed for stability?
Thank you 🙂
Another thing I am wondering about. There is a 220R decoupled by 100uF in the voltage gain transistor emitter.
The resistor value is somewhat higher than normal, but decoupled. So, it must be there for DC stability reasons? But is that a big issue with AC coupled load?
Hi, here are the files. Sorry, I made this layout only to print. The components are not named. Basic for the layout comes from Willy B. Cerna from post #79. Please look at the pictures there and check the component values and the polarity of the capacitors. May be you will find the better layout there 🙂.
regards Olaf
