OPEN SOURCE DIY Mic Project - ORS 87 - Stripped Down u87

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1​
LSK189​
JFET​
Ultra Low Noise, Low Drift, Single N-Channel JFET​
722-LSK189TO923LBK​
LSK189-TO-92-3L-BK​

It's really my mistake... But why does it work? ))))
oh man this is weird I'm not sure what to tell ya on the next board make sure the orientation the FET face is correct, you was not drinking hot fire Vodka dear friend I see you 😂
 
I fixed this annoying oversight, the microphone works well again! Apparently JFet can function in different positions, and this is very good! ))) P.S. Although no. Now the microphone produces an ultra-low signal.
 

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Yes, JFet works both ways, and the ultra-low signal was due to the fact that it was necessary to set the correct offset with the trimmer.
Korablev can I ask for permission to use your build photos on my YouTube channel CoquiAudio? I just want to show those nice photos 😊
 

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A very important addition, which was mentioned in this thread on pages 5-8.
Important.
If you are using a JFET LSK189, it has a reverse pinout, unlike the 2n3819.
It is important to pay attention to this point, since the LSK189 will work in an inverted state, but its operating mode will be incorrect.

83340-b7b5ce6a8d4412ef539344105c0315e8.jpg

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In the end, I left the JFET LSK189 in this state:

2025-01-27_18-02-14.jpg

In total, I desoldered the part and bent the central leg several times. But the legs turned out to be of high quality and withstood all the abuse. This does not always happen, and there are cases when the leg breaks off near the case, which is very, very bad. You need to be very careful.
 
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