Few Questions about UVC

[fitzroy2309]

Hello
today my UVC Kit arrived and i have a few questions...
Iam from Germany so i will use 230V.

Can anyone tell me for what the small Rectifier in parallel with the small cap (0,1µF) and the resistor(100Ohm) is? (On the Backplate)

In the Manual the ground is connected on all RCA together and via the cable on the board too, why should i do this. Its a ground loop in my opinion.

thx for your help...

regards tim

[ThorstenL]

Hi,

Originally Posted by fitzroy2309

Can anyone tell me for what the small Rectifier in parallel with the small cap (0,1µF) and the resistor(100Ohm) is? (On the Backplate)

In the Manual the ground is connected on all RCA together and via the cable on the board too, why should i do this. Its a ground loop in my opinion.

Actually, the Bridge plus RC is an Earthloop Breaker.

It in effect sits between the metal chassis, which is connected to Earth (Schutzleiter in german) and the audio circuit, which needs to be referenced to chassis for shielding, but which we ideally do not want connected to earth.

The resistor and capacitor make the connection, the diode bridge clamps any fault voltage to a safe value.

Ciao T

[fitzroy2309]

Hello,
thx a lot.

i have wired it like the plan says and everything is quiet...

Only one LED @ the Volume Control wont work.

Sound is quiet good with 100k Tantalum

regards and thx
tim

[fitzroy2309]

Hello,
it is possible to run the UVC buffer stage with 2 9V Batteries instead of the 10V from the transformer?

regards tim

[ThorstenL]

Hi,

Originally Posted by fitzroy2309

Hello,
it is possible to run the UVC buffer stage with 2 9V Batteries instead of the 10V from the transformer?

In principle - yes. However with the J-Fets the current draw is likely 20-30mA, so a pair of PP3 9V batteries will last less than 7 Hours. Also, thos batteries have a fairly high internal impedance.

Moreover, the AC based supply for the audio section includes electrostatic screens in the mains transformer (the earth terminal on the control/supply module), schottky rectifiers and LC filtering on the Audio Module with no regulators on the Buffer and a regulator for the bias voltages on the DS1666's.

It may not be as good as a battery, but it is rather good already and low impedance...

If you insist on the batteries, you may need to to stack D or C Cells (12 pcs in total) to get acceptable battery life span.

Incidentally, it is my experience that these kind of buffers used in the UVC sound better if powered all the time.

Ciao T