DIY phonostage.

[sq225917]

100pf

[mac72]

Just to make sure all buffer parts are as follow:
Q3,Q6 MJE350 PNP power transistor
Q1,Q4 PF5102 n-JFET, IDSS=6mA, VTH = -1V
Q2,Q5 J107 n-JFET, IDSS=100mA, VTH=-3V
R6,R11 2.2 Ohm
R5,R7 6.8 Ohm (on PCB as 22 Ohm)
R2 75 Ohm (on PCB as 51 Ohm)
R1,R12,R16 100 Ohm
R4,R10 1k Ohm (on PCB as 100 Ohm)
R13 1 MOhm
R14 27 Ohm
R3,R9 10 Ohm
R8a 220 Ohm
L1 10uH Inductor
R8b 2k Trimpot
C1,C2 100pF Foilcap 63V
C3 0.22uF Foilcap 63V

[mac72]

and one more thing , on the main reg board replaced J310 with J113 and resistors 3k3 with 1k , they seem to have same pinout but I remember swapping gate and source legs over , is it correct

[sq225917]

No leg swapping for J113, they just drop straight in.

Those parts are all correct.

[Bksabath]

I am really confused now VTH is same as Vgs ?

[mac72]

I think it's exactly the same thing , gate threshold volatge

[mac72]

Seems like I kind of sorted both Calvins , it took bit of tweaking of R5 R6 R7 R11 , now I run one set with all resistors @2R2 and the other one with all @6R8 , on one board which was running very low current it's input transistors biased very close to Idss , gate-source close to 0V , the other one I have no idea what causes the offset @30mV ,to increase regulation I soldered temporarily another 220R in series with 220R and I can set offset to 0V .
Once I get new matched PF5102 and all others I give it another go , hopefully it would work without too much teaking

[mac72]

Guys , how you've sorted grounding arrangement ,
I think something like mains earth to the case star ground , from there to paradise board ground and to the tonearm ground post ( C+R?)
Do you use DDRC ?

[sq225917]

Link to my Flickr acct by one of my previous pics, plenty if examples

[RothwellAudio]

Guys , how you've sorted grounding arrangement ,
I think something like mains earth to the case star ground , from there to paradise board ground and to the tonearm ground post ( C+R?)
Do you use DDRC ?

That sounds like a very bad idea.
What's DDRC?