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Shaun Perez 20th July 2003 12:42 AM

aleph p 1.7 pwr supp. questions
I am going to build my first pass diy project after reading these forums for a year now. i am going to build the aleph P 1.7 with the 1.0 volume control plus add a remote and a display for the selected input.
My first question is with the power supply ......... should i use 2 power supplies, one for left and one for right?
Is there anything to be gained from this? left-right isolation, clarity?

My next 2 questions are on the pwr. supp. circuitry:
What is the value of R121 under Q25?
What is the power ratings on all of the zeners in this circuit?
It looks to that a 1 watt zener diode will work for all of these am i right?

jleaman 20th July 2003 01:10 AM

First off. Congrats. im building one too.

see ........

Also i sujest 2 psu's one for left and the other for right.

the other on the zener's are 1 watt and 9.1v i believe.

and ill look up your question about the

(What is the value of R121 under Q25? )

jleaman 20th July 2003 01:14 AM

Where is R121 on your board.?

Shaun Perez 20th July 2003 01:35 AM

wow nice pictures!
I don't yet have a board but am planning on prototyping the circuit first and then getting the boards.

R121 is right below Q25 of the pwr supply where the 14v display board connects just below the relay voltage connect (aleph P 1.7). It is from the aleph P 1.7 service manual on

What parts sound good? audiophile at percy, parts connexion ect. or just digikey and mouser?

jleaman 20th July 2003 01:42 AM

2 Attachment(s)
Who does the boards for this Schematic you gave me..?

Dane 20th July 2003 04:08 AM

That's the factory PCB. Page 12 in the 1.7 pdf file.

jleaman 20th July 2003 04:10 AM

Just a thought and a question. Can we buy that pcb? Prolly not right ?

Shaun Perez 20th July 2003 02:42 PM

Not that i am aware of, I will probably have mine made or do them myself.

jleaman 20th July 2003 05:55 PM

Shaun When you starting your board.? I like the layout of that one but i too want a desplay and input Selector with relays.. Can you keep me posted if you also want you can talk to me Via email as i want to help if you need it and keep up 2 date with you on your project. Maybe ill pitch some money towards your way to get a board made too..

Jaac 20th July 2003 08:30 PM

iám also building a p 1.7 see my website for some pictures. i have used two power supplies.

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