AC low-power project selectable output voltages

I have recently been learning how to use a oscilloscope. I came across a product made by Velleman EDU06 oscilloscope tutor kit. You get a booklet to learn how to get the most out of your digital oscilloscope and a single sheet of paper with links to YouTube plus small icons which you can scan with a mobile device which will take you straight to each individual video.

The circuit board information:

It's a single layer printed circuit board with white printed text (signal generator board) there is a 9 V AC input,

the circuit board is well made there are testing points which give different signals (1) alternating current AC (2) adjustable AC (3) full-and half wave Rectified AC (4) ripple (5) astable oscillator

There are simple experiments

(1) measuring AC voltage

(2) adjustable AC voltage

(3) measuring AC grid frequency and period

(4) rectified AC ,signal phase

(5) rectified AC, dual phase

(6) smoothed versus unsmoothed DC ripple)

(7) DC management

(8) waveform from adjustable frequency

In the booklet it asks the following, purpose, how, how does it work, other information and exercise.

For anybody who is not used oscilloscope this little device is a good starting point to learn about the different signals.

AC low-power variable output project

I had a problem finding a AC 9 V power supply, in my junk box I had a DC isolated transformer with various outputs , the DC rectifier was damaged so this made it perfect for converting into a Low-power AC supply.

After Removing the screws then opening up the transformer case there was a small circuit board which housed a DC rectifier and a small selector which enables you to select different DC outputs voltages .

On closer inspection of the transformer the second .

Please see images.

The first thing was to take half the casing and drill a series of holes ,these house the ac voltage output selection socket, each one is connected to a different AC low-power winding pin.

There are two red leads which plug into the various sockets you simply select the letter combination for the relevant AC low-power voltage output.

I've also added an extra fuse which is on the output voltage and is mounted on the front of the case.

On the transformer I printed out a label showing the different combinations and what voltage output you can achieve

The different voltage outputs are (1.65 AC ~) (3.18 AC ~) (4.85 AC~) (6.32 AC ~) (7.83 AC~) (8.02 AC~) (11.05 AC~) (14.20 AC~)

This made a good test bench AC low-power supply which I think will come in handy for other projects that just need an AC low-power supply.

Power supplies can be dangerous, never open up a power supply transformer unless you know exactly what you are doing as these devices can contain capacitors.