Hey Ambient,Ambient said:The reason why the lm317 is getting so hot is that it has to dissipate the extra Watts. The regulator is reducing the output voltage to 9V, but if you have a 25V transformer it has to dissipate all the extra voltage and current. So it generates heat.
Just thought I'd clear that up for you, I did not notice anyone tell you why to go with a lower voltage transformer.
The LM317 was getting hot with the 25v (actually it was @ 35v!!) transformer... Hero999 addressed this and told me to use the center tap (12v).. the LM317 does not change temperature while in operation now.
The reason I added the fan is because the heatsink would not fit inside the box.. just as a precaution .. and to ensure optimum life of all parts.
Point taken.mneary: A suggestion: If the project is to go into an enclosure, you should begin there. It's easier to change the parts locations on the board before you etch it.
Yes you are correct, when the fan is turned on through my homemade (unfiltered pedal) you can hear noise.. that is why the red SPST button was added.. its used to turn the fan off when operating that particular pedal..You could ditch the fan which will prolly induce electrical noise into the DC output anyhow.
It would reduce the component count and the cost too.
Thanks and keep up the constructive feedback - it will save others much time and money in the future