Simplistic NJFET RIAA

diyAudio Chief Moderator
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Yes 300mV RMS is usable. Up to 500mV maybe, so to get 0.5mV at the -60dB MC output. The iRiaa passive networks saturate in the HF if with much input signal. They are also usually tuned for 50Ω Zout generator source. You will notice saturation when same frequency higher level square waves corners become well rounded.
 
I just assembled the PS and wondering what is the voltage out unloaded - I have 52.3 on both channels and something is telling me it is too high!

Thanks.

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diyAudio Chief Moderator
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Producing higher enough AC vs their nominal spec. At least when unloaded. If after loaded it won't result to below 50V DC you will have to up the value of the RD resistors. 10Ω value at least. So to create some RC voltage drop and counter the trend. 45V-49V DC loaded is safe. Consider 50V DC loaded as max at your local mains max.
 
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This is what happens when you finally test Ultra against as many phono pres as will show up here willing to be tested...and after building at least 8 (3 of which are amazing...but...)...yet... there are 2 decks (soon!) and 4 arms... and it's not as much fun to play with dip switches and moving cables as it is to have MORE of a GREAT thing...

...And then there's Tea-bag's "secret" Reverb shop....instant kit!

Thank you Salas (and Tea-bag).

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Having inserted components into incorrect places in past builds this is what I do now to help prevent that.
It's Tea's own ultra BOM and each component measured before adding to its cell, so when the build commences you don't have to keep stopping to verify a component. It is does add a bit of time but for me it is adds to the pleasure of the finished boards.
And you can download an STL file to print out your own resistor former (the white one beside the pcb) and it makes leg bending consistent and fast.
Just thought I'd share as many have shared to me in the past.

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This is what happens when you finally test Ultra against as many phono pres as will show up here

Thank you Salas (and Tea-bag).
Another one bites the dust sees the light!

combined with reading (of the incredible knowledge of ) Salas' threads makes it hard to withstand the itch (to build them all) — not only because its fun to do...
 
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