I just completed the first channel of my regulated pedal power supply. When I touch the transformer I can feel a slight vibration, is this ok? It gets a little warm as well. I'm an electronic engineer not an electrical engineer so I don't know 
Mikemann, any ideas?
Anyways, I'm building a 4-8 channel (undecided) regulated power supply with every channnel fully isolated from each other for my effect pedals. This is done by having seperate transformers and regulators for every channel, and is based on the spyder design from Geofex: http://www.geofex.com/Article_Folders/Spyder/spyder.htm.
The regulator I'm using is based on tangent's TREAD regulator: http://www.tangentsoft.net/elec/tread/
I'm using a 7809 instead of a LM317 because I do not require the option to vary the voltage, and this will significantly reduce the amount of components and thus reducing the size of the regulator board. The performance difference of each IC is minimal, with the LM317 being able to put out a max of 2A, and the 7809 only being able to put out a max of 1A, and the 7809 has slightly worse ripple rejection compared to the LM317. These do not affect my design as a battery operated effect pedal only draws around 60mA of current, and I believe the difference between the 2 ripple rejection ratios (68db to 80db) should not affect my application as much, as I'm powering distortion pedals, and I have quite a large filter cap (1000uF). This proved to be true because during testing, there was only a very slight hint of hiss when the pedal is turned on and I'm not playing anything. The power supply does not hum at all.
Since this was a success (except the slightly vibrating transformer, it worries me) I'm going ahead with making the rest of the channels. I wish I had monkeys to do the 'mass production' for me.. Haha.. Also I have to decide what enclosure to use for this and how am I going to go around drilling and cutting it up. I am VERY bad at mechanical work.
Below are the pictures of the prototype:
The supply powering my Keeley modded DS-1:
Closeup of it in action:
The regulator:
Better view of the components:
I used bridging:
The conclusion:
Mikemann, any ideas?Anyways, I'm building a 4-8 channel (undecided) regulated power supply with every channnel fully isolated from each other for my effect pedals. This is done by having seperate transformers and regulators for every channel, and is based on the spyder design from Geofex: http://www.geofex.com/Article_Folders/Spyder/spyder.htm.
The regulator I'm using is based on tangent's TREAD regulator: http://www.tangentsoft.net/elec/tread/
I'm using a 7809 instead of a LM317 because I do not require the option to vary the voltage, and this will significantly reduce the amount of components and thus reducing the size of the regulator board. The performance difference of each IC is minimal, with the LM317 being able to put out a max of 2A, and the 7809 only being able to put out a max of 1A, and the 7809 has slightly worse ripple rejection compared to the LM317. These do not affect my design as a battery operated effect pedal only draws around 60mA of current, and I believe the difference between the 2 ripple rejection ratios (68db to 80db) should not affect my application as much, as I'm powering distortion pedals, and I have quite a large filter cap (1000uF). This proved to be true because during testing, there was only a very slight hint of hiss when the pedal is turned on and I'm not playing anything. The power supply does not hum at all.
Since this was a success (except the slightly vibrating transformer, it worries me) I'm going ahead with making the rest of the channels. I wish I had monkeys to do the 'mass production' for me.. Haha.. Also I have to decide what enclosure to use for this and how am I going to go around drilling and cutting it up. I am VERY bad at mechanical work.
Below are the pictures of the prototype:
The supply powering my Keeley modded DS-1:
Closeup of it in action:
The regulator:
Better view of the components:
I used bridging:
The conclusion:
