Odd SIT/vFET 2SK2087C

I also just submitted a dispute claim for the full amount of $34.73 CAD.

Cody and Ben, maybe this is the universe telling us to build something else? Anyone want to try a Beast or mini beast? :) https://www.diyaudio.com/community/threads/beast-with-1000-jfets-redux.364186/page-17#post-7013040
Sure, why not? Right now you can get 2500 J113 for $332.50 from Newark. I'm guessing with a little sleuthing, we could get a larger quantity with a lesser part cost and have enough for all interested parties. Not sure who's going to do the matching, though.

Seems like a much easier build to go for a 1000 part or even a 48 part build than to deal with fake parts and non-existent parts. Maybe Papa will pass along some gerbers and we can get a Beast/Mini Beast build going.
 
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with so huge number of JFets and inclusion of source resistors, I wouldn't bother with matching at all

to avoid that - you need relatively high value of source resistor, to keep them all near the same Bay;

to compensate for increased Rout and decreased xconductance, just parallel more

to solve sum input capacitance, define size of block/cell being driven with buffer

then drive them all (Cell Buffers) with one input buffer

easy peasy
 
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ra7

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Got mine today. Vunce, we may be in luck. Looks legit. Will try to get some curves later this week.

1FCADD17-C956-432F-A008-BB7A33159584.jpeg
 
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ra7

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Nice picture...
Does 1054 have USB port to store oscillogramms on USB stick?
Yes, it can do that and it also has excellent connectivity to the PC and so you can run it from a PC app. But xy mode is not very good at plotting on screen or pics. I have also tried getting data for two channels in a csv file but there is a lot of data cleanup before anything can be plotted. Not worth the effort.

I did a bit of reading on this topic and found that digital oscilloscopes have trouble with xy mode, something to do with the refresh rate and sampling. You want either a CRT scope or a much nicer digital scope.
 
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Aliexpress offered me a full refund today.

If you receive an Aliexpress purchase that is not as described, do not click on the "Confirm receipt" button on your Aliexpress Orders webpage. If you do that, Aliexpress will release payment to the merchant. Next, wait until Aliexpress allows you to open a dispute and then dispute the sale. This strategy worked for me.
 
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Happy for you Ben.

Sadly, Aliexpress refunded me half and closed my dispute. My appeal went nowhere.

Anyway, for some reason this has really ticked me off. I'll likely not pursue any projects with this part. This is probably a sign for me to take a break from building.

I hope those who managed to get this part will have fun with it.

Cheers,
Dennis
 
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Dennis, Can you file a Paypal or credit card claim for the remainder of the money?

I am also not pursuing this SIT any further, but don't let this setback get you down. There are other interesting projects out there.

Meanwhile, enjoy some soothing music with your VFET amp and new speakers. :)