Simplistic NJFET RIAA

Who re-tipped your cartridge?

Phono Cartridge Repair

I talked to the guy today and he told me to ship my cart back. It is already on its way. Lets see how that will end.
Luckily, I got test cart today (local stereo shop borrowed it to me for 2-3 days). It is $70 Sumiko Oyster MM 4 mV.
No noise at all.
Not with bypassed SUT on FSP, and not on my old BHL (set to 60-65dB) Phono.
My original cart was noisy all over on both.
Just SUT removed about 80% of noise and this is how I used it till yesterday.

I actually surprise since that Sumiko showed very nice sound. I used my BHL and I set to 40dB since my FSP is about 70dB, and sound was not bad at all. My damaged cart is $900 and this one is $70. So, almost 13 times cheaper....:).
 
I use an Audio Technica AT-ART9 which is around 1000 usd and I am extremely happy with it.
I also heard the Audio Technica AT33PTG/II at Salas home (around 500 usd) and is excellent too, albeit a little less resolution. I' ve heard good thing about the Audio-Technica AT33Sa too.
I wouldn' t go higher in price, unless I had a much much more expensive system and room.
 
After a long time ...
I am ready (almost) to pug in my "Folded"

I have spent a few good hours of fun to find out that none of the components I had to get off the board and test where faulty.
All it was little J117 whit hi currants (as in black currants) requiring 33 and 6.whatever K instead of Boom values

This is in the instructions BTW but one could not bother reading them?

So day after tomorrow once this week 60 hour shift at DAY job is over I am going to find same more faults (hope not I am going to plug the lot in, throw her out of the house whit an excuse (here Love get £50 go and spend it all on me) and enjoy a few hours of pure bliss )

But any way just wanted to say...

I was wondering: has any one ever posted the circuit diagram whit annotated typical Voltages and such.

Please tic >>>YES<<< >>>NO<<<

IF so where is it ?

GO AND READ THIS TREAD FROM THE START.
Just answered myself so to spare the satisfaction to same XXXXXX to post it.
Apparently doing so give him rush as in the old days when he was molesting poor school children
Has usual WE reserve the right to totally disregard any spelling mistakes or show any respect to olders
 
diyAudio Chief Moderator
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Meantime I annotated for you the voltages on the main phono circuit. All in reference to ground. Keep in mind those are rough numbers because each one FSP will ask for a little different rail voltage to show correct TP. It will also have different source resistors for different IDSS 369s. But you can still check if its in a logical order by looking at those numbers.
 

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diyAudio Chief Moderator
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The 9.2 k vas giving about 2.65 V not enough to drive shunt (???) while changing the 22R to 33 R was enough to drop from 52 V to about 42

I don't think I caused to much damage else where as voltage would have dropped considerably across R1X (15R ?) due to current

R3x should be giving the major voltage contribution for the shunt's Vout. Its drop should be Q3x's in circuit IDSS (about -20% than its free IDSS) times R3x Ohmic.

R6x 22 or 33 should have an impact on Q2x's dissipation and a small difference on D2x D3x D4x total Vf as a group. Say you have 48V raw DC then you must have 42-43V DC across Q2x