e-licktronic Forum

By the way my connections are done on the solder side of the board like in your pics.

Nice, did you attach the Ground Loop Breaker?

Thanks for posting

Hi...i am a new user here. As per my knowledge you should put Cathode to diode 109 and the Anode to diode 110 from the twisted pair of diodes then the 15v from the transformer to the twisted end, your other wire connections are also correct.

So this one is ok for me? It has 230V to 2x 15V 15VA 0.5A
Living in germany.

https://www.conrad.de/de/ringkerntransf ... 09884.html

flinte413 wrote:So this one is ok for me? It has 230V to 2x 15V 15VA 0.5A
Living in germany.

https://www.conrad.de/de/ringkerntransf ... 09884.html

I read the full article now.. sorry for the question.. solved it by myself

Hi...i am a new user here. As per my knowledge the y scale is negative dB. For instance you can see a noise peak at 50Hz in both cases.
The external power supply produces a peak of about -86dB at 50Hz.The internal power supply produces a peak of about -75dB at 50Hz, which is about 10dB higher than the external power supply.Similarly, there is a second noise peak at 150Hz that is quite higher (about 8dB) with the internal toroidal transformer than with a basic external ac supply.

printed circuit assembly

LulaNord wrote:Hi...i am a new user here. As per my knowledge the y scale is negative dB. For instance you can see a noise peak at 50Hz in both cases.
The external power supply produces a peak of about -86dB at 50Hz.The internal power supply produces a peak of about -75dB at 50Hz, which is about 10dB higher than the external power supply.Similarly, there is a second noise peak at 150Hz that is quite higher (about 8dB) with the internal toroidal transformer than with a basic external ac supply.

That was my experience as well, internal was noisier. It's a big magnet after all..

Altitude wrote:

LulaNord wrote:Hi...i am a new user here. As per my knowledge the y scale is negative dB. For instance you can see a noise peak at 50Hz in both cases.
The external power supply produces a peak of about -86dB at 50Hz.The internal power supply produces a peak of about -75dB at 50Hz, which is about 10dB higher than the external power supply.Similarly, there is a second noise peak at 150Hz that is quite higher (about 8dB) with the internal toroidal transformer than with a basic external ac supply.

That was my experience as well, internal was noisier. It's a big magnet after all..

You must not have done it correctly.

Works fine. Especially with the loop breaker

Have you actually measured the noise on a scope? I have and it was nosier. Same results as LulaNord