Author Topic: Need a new Power Transformer...  (Read 1260 times)

Offline ataudio

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Need a new Power Transformer...
« on: June 28, 2015, 06:03:38 PM »
Does anyone have torodial power transformer with the following output specs:
1) 48 volts AC with center tap (24 + 24 volts).   3.5 amp output or higher
2) 44 volts AC with center tap (22 + 22 volts).   3.5 amp output or higher

Need to repair a small LM3875 chip amp.  Transformer quit yesterday.  I monkeyed in
two (25volts each) to simulate a true 48v CT transfomer and the amp still works
great.  I would like to restore it to its previous condition though. 

Offline ataudio

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Re: Need a new Power Transformer...
« Reply #1 on: June 28, 2015, 07:10:20 PM »
Correction....it has to be a low profile toroidal transformer.  The orginal is about
110mm across and only 33mm high. 

Anyone have anything of the sort let me know.

Ebay and internet turn up very high prices and trannys way to tall.

Offline bearjew

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Re: Need a new Power Transformer...
« Reply #2 on: June 29, 2015, 01:25:41 PM »
You might have luck with these guys:

http://www.antekinc.com/

A lot of people use these to create Pass Labs DIY amps.
-Audeze EL-8 Titanium headphones
-Everything else is on loan to PBJ!

Offline ataudio

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Re: Need a new Power Transformer...
« Reply #3 on: June 30, 2015, 09:13:48 AM »
Thanks BJ.  Great prices.  But unfortunately the value I need it too tall.  They show the smallest/usable xformer
at 2" tall.   I cant exceed approx 1.5 (plus some for the mounting washers/rubber pads.  Its for a 1U rack mount chassis.


Offline AdamG

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Re: Need a new Power Transformer...
« Reply #4 on: June 30, 2015, 10:39:54 AM »
You may be better off shopping ebay for a 1u amplifier being sold for parts. I'd look that direction.

Offline ataudio

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Re: Need a new Power Transformer...
« Reply #5 on: June 30, 2015, 08:35:45 PM »
BJ...Thanks again for that transformer lead.  I googled the reviews and as far as power transformers go they seem solid.  Even though none of them will fit inside the case I will
probably turn it into an "outboard" power supply. This will let me use a higher
amperage xformer and put bigger caps inside the original case.  Its an old rack mount
PA amp but based completely on the data sheet for a LM3875 amp chip.

There are many chip amp kits out there. Its just a novelty I play with but as far as chip amps go its not bad at all.  It really did surprised me as to how good it did sound...for a chip.  Honestly..not bad at all.  I will order the replacment xformer  very soon. 

Thanks again!