My uncle gave me a power amp he built from a kit ages ago.
It's 3u 19 inch rack mountable,pretty heavy and has 2 very huge capacitors,4x Hitachi mosfet transistors and a large torridal transformer plus other components.
How can I figure out how many watts in rms it gives???
Per channel there are two metal mosfet transistors.
Hitachi J50 [japan 4J2] protected by 3.5 amp fuse and Hitachi K133 [japan 4H1] protected by 9.5 amp fuse.
So could you tell me how much power in rms per channel and @ what ohms it gives it??
Also the torridal transformer sadly has a tiny piece of the insulation [about a few mm hole] on one of the secondary windings[exposing the copper wire itself]. Can I repair this without replacing the transformer instead???
It's 3u 19 inch rack mountable,pretty heavy and has 2 very huge capacitors,4x Hitachi mosfet transistors and a large torridal transformer plus other components.
How can I figure out how many watts in rms it gives???
Per channel there are two metal mosfet transistors.
Hitachi J50 [japan 4J2] protected by 3.5 amp fuse and Hitachi K133 [japan 4H1] protected by 9.5 amp fuse.
So could you tell me how much power in rms per channel and @ what ohms it gives it??
Also the torridal transformer sadly has a tiny piece of the insulation [about a few mm hole] on one of the secondary windings[exposing the copper wire itself]. Can I repair this without replacing the transformer instead???
From memory Bull, the Hitachi MOSFETS were 100W case dissipation and as such the amplifier would be no more than 50 to 60W at the outside for 8 ohms/channel.
You really need to test the power delivered into an 8 ohm load as the high on resistance and power supply limitations could impact the power output considerably.
You really need to test the power delivered into an 8 ohm load as the high on resistance and power supply limitations could impact the power output considerably.
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So I recon its btw 100w-200w per channel.
But how can I repair the torridal transformer??? its got a nick in one of the turns of the insulation on the secondary winding exposing a few mm of copper wire.
I was thinking heat shrinking but I don't wanna unwind the whole transformer. Or electrical tape maybe.... Its not high voltage but can still cause a short maybe.
So I recon its btw 100w-200w per channel.
But how can I repair the torridal transformer??? its got a nick in one of the turns of the insulation on the secondary winding exposing a few mm of copper wire.
I was thinking heat shrinking but I don't wanna unwind the whole transformer. Or electrical tape maybe.... Its not high voltage but can still cause a short maybe.
If its a kit from the UK with the J50 and SK135 then pennies to a pound of salt its the good old Maplin 150W mosfet modules (see below).
These were optimistically rated at 100W @ 8Ohm and 150W max @ 4Ohms with a max supply of 55-0-55v.
If the transformer windings still have the enamel (spelling?) intact on them then I would not worry to much, just tape it up.
These were optimistically rated at 100W @ 8Ohm and 150W max @ 4Ohms with a max supply of 55-0-55v.
If the transformer windings still have the enamel (spelling?) intact on them then I would not worry to much, just tape it up.
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