Is it possible to build a good amplifier out of junk parts?

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"effort (e.g. power transistors and alike) there's no point of not using them, unless they, as devices, are inferior in comparison to everything else you can acquire easily."

Be careful, most BJT high voltage transistors used in televisions and similar do not have adequate SOA when used for linear (audio amplifier) use.
 
Be warned - recycling old electronics will drive your wife/girlfriend/partner crazy!

now .... that sounds like Jaycee is talking from personal expirience .... i smell a screaming wife ha ha ha ha ha

my shop is 130sq meters big .... but to be able to support all the things we do we also have another place which is something between a stock room and a scrap yard and that is another 200 sqmeters

in my country a "local repair shop " is totaly 50 square meters ...

Hello sakis

I agree with you, I have many box of recycled pcboards from tv, amps, computers, vcr, dvd, and tubes from old scopes, and transformers, cases, etc... it take lot of place and can take long time to check all of them for a usefull parts to use in any prototype. But sometime I've found usefull hard to find parts in my boards and parts box.

Bye

Gaetan
 
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Where'd you get your circuit board material? Looks like the old phenolic board. Is that what it is?

se

hahaha Yes, it is! I had some pieces around. And I have painted it with white spray!!!!
I have to wear a mask when drilling this material, for it is very agressive (the powder) for breathing. (hope you understand my rough english...)
Good old times!!! hahahahahaha
Max.
 
Just take a look at these lovely things I found inside an old Epson dot matrix printer (AP2000/LX810)!!!
 

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Although the parts might be in good condition but, do u know how much have they been stressed before and when would they fail. also as said by one of the members, the performance might not be to the mark. its likely that most devices might start failing one after another. just another thought,if you convert the efforts put by you to find and desolder wont it be cheaper to buy new components from market. :)
 
Although the parts might be in good condition but, do u know how much have they been stressed before and when would they fail. also as said by one of the members, the performance might not be to the mark. its likely that most devices might start failing one after another. just another thought,if you convert the efforts put by you to find and desolder wont it be cheaper to buy new components from market. :)

Sure it will be cheaper to buy new parts! But there other situations envolved, when you are far away from big cities. There is some difficulty to have these parts due to the distance, even nowadays! There is also the need of recycling dead equipment. Brazil is becoming the worst place in the world in this issue! Piles and more piles of junk. So, there exists the need to do something! (sorry for the rough english).
Regards,
Max.
 
Here are some photos. I'm almost finished.
Thanks everybody for the nice comments! Have a nice weekend!
Best regards,
Max.
 

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Also I find a propane torch is much faster than the solder iron to remove parts from a PCB.

Got to try that torch trick! :eek:

I usually grab all PSUs, old amps and PC monitors for the parts hidden inside. Some parts are really valuable, like rectifiers, diodes, power transistors. Other parts are rather odd: I once found a TDA2006 in a monitor.... :confused: :D

@smartx21: what is the general layout of this amp? Class A mono?
 
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Got to try that torch trick! :eek:

I usually grab all PSUs, old amps and PC monitors for the parts hidden inside. Some parts are really valuable, like rectifiers, diodes, power transistors. Other parts are rather odd: I once found a TDA2006 in a monitor.... :confused: :D

@smartx21: what is the general layout of this amp? Class A mono?

Sorry, I wouldn't like to discuss about the specific type of the amp, due to restrictions imposed by the circuit's author, in order not to dimish its image beyond the forum. A small look around and you will find it, for being very familiar to this forum. Originally, it is said to be one of the best ever seen here.
Even though, after being operational, I will post the results.
Regards,
Max.

(I apologize for the rough english).
 
Almost there!

Some details. Attempt to the output coil, removed from an IBM PC100 PSU! The 10R resistor is a bit out of especifications for the output power, but I will look for the correct one!
 

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First unit done!

It is past midnight, my wife must be angry with me...
This is the finished first unit.
Tomorrow I expect to have it tested!
 

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The answer is: YES, IT IS!!!

Well, definitely it is! The sound is SUPERB! :eek:
No need to adjust anything than bias! No problem, no excessive heat, only glory!
Thanks to very good project from the forum!!!
Of course transistors were all new, but sometime I will try with some old used parts.
Let me listen for a while.
Thanks!
Max.:cool:
 

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