Voltage Regulators

I'm tried to do my ps but I'm having some problems. I ended up burning out
one of the regulators for some reason but the real issue is that the
regulators don't seem to be regulating.

If I setup a very basic transformer->rectifier->filter->regulator

then with no load I get the right voltage but with a 2.2k ohm + LED load the
voltage drops from 8 to 4. Its a MC78M08 regulator and surely it shoudln't
drop 4 volts at that load? I don't use any of the "extra" stuff such as
protection diodes and ripple reducing capacitors and the voltage I'm putting
in is about 35 volts.

The transformer is a 25.2VCT and I'm using the full secondary. The bridge is
4A@600V and the filter cap is a 200V @ 1mF(I know I could use a larger one
but surely it is enough).

As far as I can tell I'm not getting any.............


hmmmmmm


WTF. I just switched my DMM down to 20V cause I was measuring it on 200 and
now its reading 7.74V with variations going from +- 1V about every second.

I didn't know I had to choose the right voltage range on my DMM to get an
accurate reading ;/ Is this true? That really sucks if so ;/

i.e., turning the switch to 200V gives me a reading of 4.4V and switching it
to 20V gives a reading of 7.74V. Any reason why it would do this? Low
battery? Messed up meter? Or do I just need to make sure to select the
proper range?(which seems kinda odd cause you would have to know it ~ before
hand).

Thanks,
Jon


.

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