@pico
D1 should be correctly connected as you can se from one of the picture above.
Pass says that this should drawind down the dc voltage when the power supply is turned off. that is not what actually happens. the led stays on for a long time
What it does is set the gate voltage to 9V so that Vgs is set to around 0V (with an 18V supply), this is important for the correct operation of the buffer
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@pico
Vds=17,2V
You also need to measure Vgs not just Vds.
Vds should be around 9V not 17.2V
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Stop using a remote server.
Attach your pics so that we see Thumbnails that load very quickly and can expand whichever Thumbnail we require to see @ full size.
Each time I load or re-load a page I have to wait for the remote server to download every pic file in full size. It is infuriating having to wait, before I can do a refresh.
Attach your pics so that we see Thumbnails that load very quickly and can expand whichever Thumbnail we require to see @ full size.
Each time I load or re-load a page I have to wait for the remote server to download every pic file in full size. It is infuriating having to wait, before I can do a refresh.
Vgs should be around 0V.@pico
Sorry I gave you a wrong info.... I wrote Vds instead of Vgs
If it is 17V you have a problem.
Measure Vds.
Also measure voltage from gate to ground.
AndrewT I'm sorry, I did not want to enrage anyone, I simply chose the most convenient way to do things, but I promise that from now on will attach the file directly.
Vds across Q100 should be around 9 V.@pico
Vds=18V
V gate to ground=0,7V
V gate to ground should also be around 9V in order to give you Vgs of 0V.
Just out of curiosity can you measure Vds across Q201 and Q101.
Is there any chance you have shorted R3, C2 or C3 to ground that could explain V gate to ground of around 0V
Measure resistance across R3/C2/C3.
Whichever one is easiest to measure across will do.
Whichever one is easiest to measure across will do.
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Do you measure 10k or something elseanyway No shorts between ground an r3/C2/C3
This is important
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