Philips 40/25/15 watts amplifier with Universal preamplifier circuit.

[renjiish]

my dear DIY brothers

this is regarding a circuit developed by Philips in 1970's. it is a 40/25/15 watts amplifier with Universal preamplifier circuit. it was very popular in DIY groups at that time. it use to give a very good quality of sound, eventhough it was a AC coupled amplifier. originally the output transistors are BD182. but most of the people used with 2n3055.

do anybody have the circuit diagram. i got some printed circuit boards without circuit diagram.

regards
renjish

[gmphadte]

Those who had the diagram are now in their late fifties and don't login at DIYAUDIO.com. They have enough problems of their own and will definately not take the trouble to scan the diagram and post it here.

To make the story short, dump that over 3 decade old pcb, search the net and make yourself a new design power amp.
2N3055 is an old transistor by design and does not sound good. There are many that sound good and are easy to install.
Go to the site sound.westhost.com and u will find preamp circuits that will work equally good.

Gajanan Phadte

[tomtt]

a (much) better regard for things Philips here


http://forum.mfbfreaks.nl/


http://www.mfbfreaks.nl/


38

[destroyer X]

The files are in PDF.... they are 300K size.

Write me a mail with your adress if you are interested, than i will be able to upload you the pdf files.

regards,

Carlos

[destroyer X]

mounted in a single board....also the ballance and supply...a complete stereo...low powered old unit from Philips.

My mail is:

panzertoo@yahoo.com

regards,

Carlos

[gmphadte]

to assemble something better or learn the hard way. When u compare this with the never products, only then u will know the reality.
This circuit was sunding good in seventies.

It is good to see DestroyerX has put up the circuit details. He is always and ever-ready to help.

But...
from your post I get it that just because u have the PCB, u want to assemble it. Remember in today's standards, this circuit stands nowhere. One reason is that it uses a single supply which needs an output capacitor for coupling the speaker.This sounds bad. I can see other reasons also but I am not competent enough to explain.

Select a good sounding circuit depending on your power requirement and go for it.
If u are in metro, it is easy to get a quality pcb made or make yourself one with the toner transfer method.

Or simply draw the tracks on a laminate using nail polish/oil paint and etch it.

Learning whichever way is better than not-at-all.

Gajanan Phadte

[satin]

I still have this amp in working condition,& i can provide ckt diagram if required.
my email id is suppal005@redifmail.com

[vinoth]

Hi

I am planning to make home theater with philips transistorised circuit with unversal pre ampifier,
already i had made home theater with TDA2020 with 741 pre amp

Pl suggest me will phillips transistorised amp will provide me the excellent detailed sound quality as compared to other amps? or can any one suggest me which one i can do.
my mail id is
www_vinoth@rediffmail.com

[Pabloso]

In Argentina this circuit has named "Fapesa".
Schema and layout is here: Tecnicosaurios.com • Ver Topic - Amplificadores FAPESA.
The file is "70.pdf"
Registration is needed, but is free.
P.D Sorry for my bad english...

[destroyer X]

Some foruns are doing this way to force us to register... a pity that, i do the opposite, no way to accept that demand....that forum does not make a friendly presentation to our communitty.

I know that you are not the forum owner hermano, but these guys should understand that they may be loosing members this way.. something goes covering text...very annoying, very rude.

Good are foruns where we do not feel the management presence, not to feel alike a fish inside a glass pot, beeing observed, controled (moderated)... alike a prisoner watched by cameras.

Saludos brasilênos hermano Sudamericano.

Carlos