I know there is a problem is my circuit but I cant find it (Learning the basics)

Your schematic shows you're using a PNP for TR1 and TR2 and it should be a NPN., the part numbers are NPN so are these the parts your using.

A PNP transistor will flow current from emitter to collector, An NPN is Collector to Emitter (I know,..... i'm using practical Electronics, not Real electron flow)

So you need to change it to an NPN. This is assuming the schematic is correct real components are not. And not just a drawing error with the diagram

Secondly the PN108 is a photo transistor from all the data sheets I have found and as such will be very susceptible to light turning it on and off you should not be using this device for this circuit use a BC108 or  2N22222N2222 or any other general purpose NPN transistor just not a photo transistor It probably looks like it has a glass top or plastic semi transparent top on it

You did not say what was the behaviour of you circuit and why you thought it was not working

Hope this will help, the rest on first scan looks correct.

Im betting you got these transistors from re-cycled boards or obsolete parts ??

Same as Robert Peter Oakes plus put C1 in the right polarity, and output should be positive, whereas there is a minus sign(¿?).

Where did you get the schematic?

Zener diode is backwards too.

It the end of the school year.  Is this a take home test?

This is a negative voltage output power supply.  Some might say the diode bridge is connect wrong.8^)

Maybe only inverting each diode of the bridge (D1, D2, D3 and D4)? Remain PNP transistors. Then you get regulated negative voltage? But we still have the problem with the model of the transistors...

If this is supposed to be a test  for you, a good hint is that at least one of the answers so far is correct. If it is not a test and you need this circuit to work, explain a little more about what this power supply is for or what you are trying to learn from it.

I am starting to think its a test for us , kinda like "How many things can you find wrong, provide the number and the winner gets a prize

Would you care to share what book this is out of.

The background of the scan seems to indicate some form of published drawing (versus your own)

I am picking that it is a test, and that it probably requires answering in order to complete.

There are quite a few errors.

Mark

this diagram is for a proposed new d.c regulated power supply. it is required to produce a negative voltage of -14V with respect to ground. Thanks by the way for you help! can you spot anything else or is that all?