JFET FX loop, some questions (schem)

[Aharon]

Hi everybody.I'm thinking of building this loop,I found some  minor differences between the pcb and schem,has anybody built it?
Also,can the MAXX chip be used instead?,I see that pins 1 and 8 are tied so I think it's ok.
Resistor on transistor base is 1.8k in schem and 6.8k in pcb.
Output cap 1uF schem,2.2uF pcb.
Thanks in advance.
Aharon