DIY Sony VFET pt 1

The typo okay, but last night I looked at your pdf, and even with my limited knowledge, I concluded it was not two switches.

You specified a DPDT and the only reason for that would be for the two marked on the schematic as SPST x 2 = 1 DPDT.

Anyway, congrats to all the greedy boys/girls who won the last round. I'm happy for you all... no really I am, okay maybe not happy, but glad, yes glad that's it.... well maybe not glad... Okay, stay away from freezers and backhoes for the next little while. :smash: :p

(Lest anyone take that seriously, I am happy for you all and wish you no ill will) mostly :p

JT
 
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I received a PM from a member regarding the N Vfet PS filter as he might want to use it for his ACA/ P VFET. Others might be tempted as well, so here below some pics:

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and yes the resistors are 5 w:
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I guess it would not be too difficult to do on a perfboard.
 

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This PSU board arranges the relay contacts to be in parallel with the loudspeaker. While the supply voltage is ramping up (@ power-on) or ramping down (@ power-off), Nelson's circuit closes the relay contacts. This means the loudspeaker(+) terminal is shorted to the loudspeaker(-) terminal in both channels, during power-on and power-off events. And of course the relay contacts are also closed, shorting out the loudspeakers, the whole time the amp is turned off.

The VFET amp channel board is AC coupled to the loudspeaker through a very large electrolytic capacitor on that board. So the signal applied to the loudspeaker is AC (not DC) and the relay contacts are required to switch AC (not DC).



_
 

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I just received my parts kit. Also confirmed that the shipped switch is SPST. My chassis is vacationing in Paris, so don't have it to double check. I did have some CW GRS-4021 in my parts bin and they are the same dimensions. Good news is that both Mouser (15 variations) and Digi-Key have them in stock in the US.
 
I just received my parts kit. Also confirmed that the shipped switch is SPST. My chassis is vacationing in Paris, so don't have it to double check. I did have some CW GRS-4021 in my parts bin and they are the same dimensions. Good news is that both Mouser (15 variations) and Digi-Key have them in stock in the US.

Great thank you for the part number that was my next question!
 
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Joined 2012
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Looks like the correction caused an issue down the line. Also the PS board shows the LED circuit connected directly to the Supply V+.

It's reminiscent of my day job when I designed building structures. Pesky issues would crop up when back-checking structural drawings as changes would affect other parts of the drawing, necessitating more changes.:)
 

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