transformer needed

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ok, ive looked over the spec sheets for my DIY Kit #50 (from qkits), and im not 100% sure which transformer i need.

im building a stereo unit, with 2 kit 50's, and 1 power supply kit #114. (do i need a power supply kit for each module? or just 1 for the stereo?).

it says i need a transformer that is rated at 60VA with a 35V center tapped secondary winding. however, it says for stereo, you need an 80VA transformer... the rails are +-25V.

ok, im confused. what do i need? i just want 1 tranformer for both channels. can someone help me out?
 

Electro

Member
2002-04-12 4:41 am
60VA means wattage. You need to find a 60 or 80 watt transformer. You can always go a little higher on wattage but stay with in volt limits.

When the sheet says +/-25 it means find a tranformer that is rated 50 volts or 25-0-25. Also making a power supply for amplifiers like QK114 is very easy. You may want to get 4 or 6 amp diodes. It is best to double on everything when making power supplies.
 

taylor

Member
2001-10-04 9:10 pm
LM1875 transformer

That kit uses the LM1875 IC which has been thoroughly researched on the web as a "gainclone" The 60-80VA rating is really a get by number. Im using a 225VA 36VCT(center tapped 18-0-18) I just bought a cheap 25VCT 125VA (5amp) from All Electric for a measily $16 to power a LM1875 garage amp. Do yourself a favor a check out Elliot Sound Products site for excellent explanations of the LM1875 circuit , supply for it, and audio components/building in general.
http://sound.westhost.com/index.html
Also checkout the these "gainclone" sites.
http://www.geocities.com/rjm003.geo/rjmaudio/diy_gc.html
http://pub4.ezboard.com/ffakeidsfrm1
http://www.interlog.com/~cfraser/Gainclonehome.htm

good luck, taylor
 
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