IMPOSSIBLE TO REMOVE HUM IN PHONO PREAMP

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Friends. I built a phono preamp, based on circuits of Rod Elliott. I used good quality components and OPA2134 operational. The construction was carried out by placing the transformer pre cabinet, using a specific one for him. The interconnection notif them has been done with three wire mesh, where the mesh is connected to the network by a mass and on the other side to mass pre star. The issue is that there is always a hum auque is low. It is never silent. Post diagrams to help me that I was wrong. Greetings Jose.
An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.
 
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Which is the AC voltage at the secondary of the trafo?. It says 7VA, but it is power. Perhaps, the voltage at the 4700 micro is few to the 78/79 to regulate (no drop out or too low), and hum goes though power lines. You need almost 12/15V, so have 20VDC at C1/C2, and personally unlike this voltage doubler. Don´t you have a 12+12V /100mA and make a Graetz bridge instead of this doubler?
 
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The PSU is appauling, it is only half-wave rectified. Try a decent centre-tapped transformer correctly rated at 12-0-12V and using a full bridge rectifier.

12-0-12 will give you the required headroom for the regulators. No-one in their right mind would use a voltage doubler at this voltage.
 
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I have the same type of voltage doubler in an amplifier without voltage stabilizer and I do not have any hum.
If it is well calculated a voltage stabilizer can work well.

What is the voltage on filtering capacitors from input of voltage stabilizers?

AND

With input in short-circuit the hum it is present?
 
Modified PSU with CT transformer

Try a decent PSU.
 

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OK. I'm using a transformer with CT. I put a diode bridge for full wave rectification. The voltage on C1 and C2 is + - 20v. And as if you hum with the inputs shorted, not tried. I think I need to change the PCB that is not the original of Rod Elliott. PCB shipping diagram used. I appreciate your information. Jose.
Postscript: If you disconnect the wires from the in put (those coming from the turntable) only blows at max volume.
An externally hosted image should be here but it was not working when we last tested it.
 
Thank you all. I solicionado the problem Hum. I have realized simply a ground plane on the side of the PCB welding, with a fiberglass board with copper, the same size of the PCB. welding the copper circuit ground of this plate into several symmetrical points.* Of course, supporting the fiber side of the circuit.** Now zero hum and maximum volume (in a Rotel RA-970BX) only hear at least sssssss. Please provide your feedback, Joe.
 
Thank you all. I solicionado the problem Hum. I have realized simply a ground plane on the side of the PCB welding, with a fiberglass board with copper, the same size of the PCB. welding the copper circuit ground of this plate into several symmetrical points.* Of course, supporting the fiber side of the circuit.** Now zero hum and maximum volume (in a Rotel RA-970BX) only hear at least sssssss. Thanks for giving your opinions, José
 
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