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kevin gilmore

Megatron Electrostatic Headphone Amplifier

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Just to double-check...these are the same diodes found in the old PSU (STTH1210D), you're saying we can't use these anymore? A quick google search doesn't yield anything meaningful for stth512fb

 

While we're at it, can we still use the KBU* part for the new psu's LV bridge (vs RS402L)?

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Those are not isolated diodes so it will explode quite spectacularly. 

 

Same bridge is used. 

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Those are not isolated diodes so it will explode quite spectacularly. 

 

Same bridge is used. 

 

Yes, I think that was already covered somewhere in this thread or the KGSSHV thread.

But could he not go about isolating them with some Kapton? Would not be pretty and would need to ensure it stayed in place from a mechanical perspective. Obviously the correct parts would be the best approach.

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Thats because its a typo and should be stth512fp

 

Just to double-check...these are the same diodes found in the old PSU (STTH1210D), you're saying we can't use these anymore? A quick google search doesn't yield anything meaningful for stth512fb

 

While we're at it, can we still use the KBU* part for the new psu's LV bridge (vs RS402L)?

Edited by insanity

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We are dealing with a lot of raw DC voltage here so the only option is to use the isolated diodes.  Any other route may work but it probably won't. 

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Well, I will change them before they explode :)

The 1210 is TO220

The 1512 at mouser is DO247

Edited by eggil

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Alternatively, he may only need to replace two rather than all four (in each grouping) - two insulated beside two uninsulated. Just a thought.

Edited by GeorgeP

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Wondering how everyone else is coming along with their Megatron build?

 

I'm getting jittery waiting for the call that the rest of my items have arrived. This is my first tube project so was hoping for more info before I plonk everything in and power it all up :P

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power and filament transformer arriving from sumr this weekend, should be able to finish (finally). Going to try the input stage with AC first, but I have a Millet Regulator lying around as well.

 

Mundorf supreme leads are too thick for the wima spots, for anyone that was curious

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Just did a power-on test with everything on the floor. It powers up nicely! :D

 

Left it running for about 10 mins... no sparks and all... pretty stoked! Late over here now... will do the sound test tomorrow - going to have trouble focusing tomorrow!

 

Offset/bias didn't go above 3.5V for the time I had it up running.

 

Some night pictures:

 

58WrWMu.jpg

 

PNcd4Q9.jpg

Edited by RiStaR
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congratulations, that offset is better than what I can adjust to in my kgsshv

 

Cheers! Good luck to you when you power yours on over the weekend, too!

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[Just did a power-on test with everything on the floor. It powers up nicely! :D

Left it running for about 10 mins... no sparks and all... pretty stoked! Late over here now... will do the sound test tomorrow - going to have trouble focusing tomorrow!

Offset/bias didn't go above 3.5V for the time I had it up running.]

Mama Mia ! :0

Edited by eggil

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Cheers Wachara and Eggil :)

 

I can't wait to go back and hook it up to a source and it's only mid-day here :P

 

Hopefully everything works fine then I can focus on all the other parts (so much more to go!)

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Thanks Joamat :)

 

You're still the first to build it! Really looking forward to heading home and testing it tonight.

 

palchiu: It's the KGSSHV PS board... the BOM for that is also on that site.

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