How to make a audio amplifier using D2390 and B1560 transistors

Ian0

Joined Aug 7, 2020
4,840
here you are. Enjoy!

Unlabelled R and C on the input = 22k and 2.2uF
transistors in first stage = BC546/7/8 or BC846/7/8 and BC556/7/8 or BC856/7/8, or Use the BCM84x BC85x matched pairs. If you need more voltage use 2SA1312/2sc3324, and replace IRF510 by IRF610.
 

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MisterBill2

Joined Jan 23, 2018
11,581
From the pictures it appears that you already have a decent amplifier. My suggestion is to locate the service manual and find the circuit, and then determine what connections go to which of the connectors on that circuit board.
 

Thread Starter

Dinnaka

Joined Dec 13, 2020
4
From the pictures it appears that you already have a decent amplifier. My suggestion is to locate the service manual and find the circuit, and then determine what connections go to which of the connectors on that circuit board.
Thank you for reply. It's correct. But this circuit is 6 channel output. Bit I want a make 2 channel stereo amplifier using this all transistos.
 

Audioguru again

Joined Oct 21, 2019
4,524
You have the seven channels amplifier, we do not have it.
Why don't you simply copy two of its channels?

Use a modern cast aluminum heatsink instead of the tin can one it has.
 

MisterBill2

Joined Jan 23, 2018
11,581
Since you have seven channels that appear to all have one output side common , it should be possible to use them as pairs of bridged amplifiers, giving you at least twice the output power capability, and having three extras as spares.
I realize that the shape is inconvenient, but it should be possible to create an enclosure to use it. AND it seems likely that you also have the power supply to go with these seven amplifiers. That should work well if it only has to power four of them.

It may also be possible to separate each amplifier segment by very carefully cutting the circuit board between channels. Of course you will need to trace the circuit to know where the connections would be. If your electronics background is not adequate for that, don't try it, though.
 

mazatech

Joined Dec 8, 2021
11
here you are. Enjoy!

Unlabelled R and C on the input = 22k and 2.2uF
transistors in first stage = BC546/7/8 or BC846/7/8 and BC556/7/8 or BC856/7/8, or Use the BCM84x BC85x matched pairs. If you need more voltage use 2SA1312/2sc3324, and replace IRF510 by IRF610.
much better!! ;) seems to be good...what value is the last capacitor to ground ?
 

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MisterBill2

Joined Jan 23, 2018
11,581
I suggest tracing the circuit of the current amplifier, if that one was acceptable. AND I suggest examining the circuit board to see if separating the amplifiers can be done easily. That could be a simple process and save a lot of construction time.
BUT you MUST have adequate soldering skills or the whole thing will be a waste of time.
 

mazatech

Joined Dec 8, 2021
11
I suggest tracing the circuit of the current amplifier, if that one was acceptable. AND I suggest examining the circuit board to see if separating the amplifiers can be done easily. That could be a simple process and save a lot of construction time.
BUT you MUST have adequate soldering skills or the whole thing will be a waste of time.
a simple bufferamp should also work...or what do u think? i have some pioneer boards for experiments too and like the circuit of ian ... maybe i'll try it but you are right ...current amp. is needed
 

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Ian0

Joined Aug 7, 2020
4,840
much better!! ;) seems to be good...what value is the last capacitor to ground ?
It is >33μF. It sets the low-frequency roll-off as f=1/(2πRC). 33μF gives a roll-off of 10Hz.
I don't see why you need a buffer amplifier. The input impedance is ≈22k.
 

MisterBill2

Joined Jan 23, 2018
11,581
IS THAT THE CIRCUIT? Shown in post #9?? or is that just a good amplifier circuit? Or one submitted to show the TS what can be available? The circuit in post #12 is just a pre amplifier, drawn in the general arrangement of a power amp, a bit confusing at first glance.
 

mazatech

Joined Dec 8, 2021
11
IS THAT THE CIRCUIT? Shown in post #9?? or is that just a good amplifier circuit? Or one submitted to show the TS what can be available? The circuit in post #12 is just a pre amplifier, drawn in the general arrangement of a power amp, a bit confusing at first glance.
#9 is the circuit of ian (with only some µA at the output) #12 is the bufferamp (stage before tone control) of a pioneer a616 mk2 ...no simple preamp Vin =Vout only current is boosted... confusing at the first look but a good way to draw a 2 channel amp circuit i think
 

mazatech

Joined Dec 8, 2021
11
IS THAT THE CIRCUIT? Shown in post #9?? or is that just a good amplifier circuit? Or one submitted to show the TS what can be available? The circuit in post #12 is just a pre amplifier, drawn in the general arrangement of a power amp, a bit confusing at first glance.
if dinnaka tells me from which model the poweramp assy is i can give him the circuit ...its nearly the same in each pioneer amp with these transistors ...looking like this ...but for the exact one i need the mod. nr.
 

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MisterBill2

Joined Jan 23, 2018
11,581
if dinnaka tells me from which model the poweramp assy is i can give him the circuit ...its nearly the same in each pioneer amp with these transistors ...looking like this ...but for the exact one i need the mod. nr.
OK, now what do you think about the possibility of separating pairs of these amplifiers by cutting the PCB. It seems that more power can be available by running two of them in the bridge arrangement, with only a simple phase inverter required. That seems like a simple way to get twice the power, or maybe four times the power, although the amplifiers are limited in the current that they can supply. But at least twice the power.
We can not tell because we can not see the foil side of the boards. If each amp is more separate, then it could be done.
 
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