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Solid State Amplifiers => Amplifier Discussion => Topic started by: mwdavis on November 06, 2019, 08:21:36 PM

Title: National GA920P Help
Post by: mwdavis on November 06, 2019, 08:21:36 PM
Hi all,

If I need to replace the transformer on this little amp (National GA920P), can anyone tell me what I would need?  This particular unit was purchased in Germany, so it's wired for 220V.  I need 120V 60Hz.

Thanks to everyone!
Title: Re: National GA920P Help
Post by: Enzo on November 06, 2019, 11:10:51 PM
There is a thread about this model right on this forum.

The power supply is a simple single voltage.  Look at your power transformer.  Are there any unused wires coming from it?  Or are the wires that connect with the mains cord doubled?   If so, you MIGHT have a dual voltage transformer.  I tend to doubt it, but looking is free.

Looking at the thread, further down is a real schematic, it appears you need a transformer that produces  26-0-26 volts AC.  SLightly odd values, so 24-0-24 would work just fine and be easier to find.  That is same as 48vCT  (Center Tapped)