I'm not actually worried about Lm7812

 

Hahaha...
Good point!
I suppose this is the datasheet for the LM7812? Because, on my circuit I'm having LM7824 which is rated at 40V if I'm not wrong? And, also, if I am getting let's say about 35V peak to peak, won't the voltage drop across the rectifying diodes lower that down before it gets to linear voltage regulator?

 

And, also, if I am getting let's say about 35V peak to peak, won't the voltage drop across the rectifying diodes lower that down before it gets to linear voltage regulator?

Yes. About 0.7V per diode only.
I tend to ignore that for most designs, unless the volts are borderline, as the output of the transformer will vary much more than that with mains variation and loading changes.

 

Well, ok, reasonable.
However, what do you suggest me to do now? I don't want to spend another 15-20€ on a transformer as I do have this one. If there is no way to lower its output voltage, then I'm kind of out of options? And, even if I do buy a new one, wouldn't it also giving out 27-ish volts on the output without any load on it?

 

Is here any gap between the core and the winding of the transformer?
If so, you could add turns of wire to hook in series with the other winding, but in reverse, to lower the output voltage.
Another option would be to take some turns off the transformer secondary.
Yet another way would be to connect a number of power diodes in series to drop the volts that way.
Bridge rectifiers may be used as the diodes. There are a few places to hook them in.
In series with the secondary AC, or from the bridge +ve out but before the capacitors.
If in the AC line, diodes both ways will be needed. Both options can use bridge rectifiers wired appropriately to drop the volts.

 

Is here any gap between the core and the winding of the transformer?
If so, you could add turns of wire to hook in series with the other winding, but in reverse, to lower the output voltage.
Another option would be to take some turns off the transformer secondary.
Yet another way would be to connect a number of power diodes in series to drop the volts that way.
Bridge rectifiers may be used as the diodes. There are a few places to hook them in.
In series with the secondary AC, or from the bridge +ve out but before the capacitors.
If in the AC line, diodes both ways will be needed. Both options can use bridge rectifiers wired appropriately to drop the volts.

How many diodes would i need to drop from 28vac to 24vac and what power should diodes be.

 

Disconnect the bridge rectifier "+" pin from the circuit.
Using a spare bridge rectifier as power diodes....
hook the "~" pins together. may not actually be needed.
"-" pin to the original bridge rectifier "+"
"+" pin to the filter cap where the original bridge was connected.
This will give you 2 diodes in series. Actually, 2 parallel pairs of diodes in series.
The voltage drop will be about 1.4V so if you have 3 sets of these diodes (bridges) in series, that is 6 diode drops, it will lower the volts to the filter cap by about 4volts.
You could just put 6 power diodes in series but using bridge rectifiers may be an easier and cheaper way to get the power diodes.
A source of power bridge rectifiers may be old TV sets or computer monitors.
I'm in bed now and using the iPad but if you need a diagram I can draw one up and scan it in tomorrow.

 

Disconnect the bridge rectifier "+" pin from the circuit.
Using a spare bridge rectifier as power diodes....
hook the "~" pins together. may not actually be needed.
"-" pin to the original bridge rectifier "+"
"+" pin to the filter cap where the original bridge was connected.
This will give you 2 dioded in series. Actually, 2 parallel pairs of diodes in series.
The voltage drop will be about 1.5V, so if you has 3 sets of these diodes (bridges) in series, that is 6 diode drops, it will lower the volts to the filter cap by about 4volts.
You could just put 6 power diodes in series but using bridge rectifiers may be an easier and cheaper way to get the power diodes.
A source of power bridge rectifiers may be old TV sets or computer monitors.
I'm in bed now and using the iPad but if you need a diagram I can draw one up and scan it in tomorrow.

I will search today for some bridge rectifires in my parts bin and wait for tommorow so you could draw me that diagram thanks in advance.

 

My Dear Lady is a bit crook so we will not be getting to sleep for a while.
So, here is a quick scribble...

I hope that helps.

 

This is what i found in parts bin could i put 2 bridge rectifires and 2 of these big diodes to make up what you drew inprevious post

 

Do you have any labels on those rectifiers? Have you checked that they can handle 2A of current?
Also, what diodes are you using?

 

Do you have any labels on those rectifiers? Have you checked that they can handle 2A of current?
Also, what diodes are you using?

Diodes and rectifires are rated for 3 amps

 

I just finished putting rectifires and diodes in and i am getting 34.6v across c1i think thats a bit high could i add another diode to lower the voltage under 34v

 

How much of a Voltage drop is it comparing to original wiring?

 

How much of a Voltage drop is it comparing to original wiring?

I didn't check voltage before this because i was afraid i would burn the ic with 28v at the input

 

Did you put another diode? How much are you getting out now? Is it working?

 

Did you put another diode? How much are you getting out now? Is it working?

I didn't put another diode it's working good on 6 diodes

 

My PCB should arrive this week, and in the meanwhile I'm preparing everything for it.
Now, as I am really worried about that overvoltage my transformer spits out, I stumbled upon this:
https://www.njuskalo.hr/elektronski...-napajanje-70w-210w-23.6v-8.8a-oglas-22564340
It is in Croatian language, but I believe that you might be able to figure out from stickers on the product if that would work. And why not.

 

I don't think that is actually a transformer. The label, "Electronic Transformer" usually denoted a switch mode device.

 

Yep, I agree.
But, basically, it does take a 230VAC in and gives out 23.6VAC out? Right? Wrong?