🚀 go-pugleaf

In article <kZzetgW00Xc=M4x0R=@andrew.cmu.edu> cl2n+@andrew.cmu.edu (Christopher Fleming Lane) writes:
>Help,
>
>A friend and I found the schematics for a 250 Watt amp.  It is very easy
>to build and cheap except
>for the power supply.  It requires a 106 V 10 Amp transformer and two
>10,000 uF capacitors.  The price of these three things is about $100. 
>Anyone know where we can find better prices or devices
>from which these components can be salvaged.  Also, 106 seems very close
>to wall socket voltage.  Would going straight from the wall without the
>transformer be a really dumb idea?  Is the transformer stabalizing the
>voltage or what?  Any help would be much appreciated.
>
>C. Lane

You can get a 105V, 8A power transformer from Mark V electronics.  It's
a standard iron core transformer, nothing fancy.  Check the back of 
a recent Radio Electronics issue for the address and phone number.
I bought one of these beasts from them a few months ago for about $38.00.
It weighs in at at around 10 pounds or so.  You can probably get away with 
this beast as it has capability for 840VA.  With 60% efficiency in your 
amplifier, typical for class AB, which is what the amp design probably is, 
you would get 504W RMS output total and you said the power amp is 250W (per 
channel I assume).  Besides, you won't be listening to sine waves, 
I hope :-)  The capacitors will be a little tougher to cut the cost down.  
I got 9600uF caps at 100V from ham fest flea markets for 50 cents a piece; if
you can find such a flea market in your area, you should check it out.
Otherwise, you may have to shell out the bucks for these things.  Maybe 
someone else out there can help you with the caps.

Andrew Karanicolas
MIT Microsystems Laboratory
ankleand@caf.mit.edu