Oakley PCB Issue 2, User Manual

Page 1: ...Oakley Sound Systems Power Supply Unit PSU PCB Issue 2 User Manual V2 3 4 Tony Allgood B Eng PGCE Oakley Sound Systems CARLISLE United Kingdom 1...

Page 2: ...o your source of power any external switches and the optional power indicators We will also look at the Oakley power buss and how it differs from the MOTM one yet retains complete compatibility with i...

Page 3: ...to the mains or other high voltage sources further to what is provided in this document Please do not ask us for additional information pertaining to direct mains connections or using internally mount...

Page 4: ...one of a positive voltage the other a negative one These voltages are measured with respect to a common ground which is normally connected via your house s wiring to the earth that you stand on The v...

Page 5: ...oad of 0 94A Once rectified and smoothed this means that a maximum current of 0 52A can be drawn from the PA 20 Two sets of screw terminal blocks are provided for connecting the low voltage AC power s...

Page 6: ...y board should go back to the PSU separately A wallwart is the vernacular term for a low voltage mains adapter that plugs directly into the wall These take the form of a black plastic block that is sh...

Page 7: ...ent draw of your PSU For use with this board I recommend the Yamaha PA 20 and PA 30 supplies Yamaha PA 20 This is a linelump supply and features a fixed 17 5 0 17 5 volt AC output at 0 94A maximum Thi...

Page 8: ...t is for your own MG12 4 mixer Once rectified smoothed and regulated the Yamaha PA 20 can deliver up to 0 52A continuously into both 15V rails The current limit resistors on the Oakley PSU R2 and R3 s...

Page 9: ...o wires come out of the wallwart and that you can select from a variety of output socket types Simply chose the one you would like to use on your system and buy the appropriate socket for it to go int...

Page 10: ...nd S1S together when switched on You can replace the switch with a simple wire link but I do recommend that a switch be fitted so the socket doesn t have to take the full surge current when you insert...

Page 11: ...ogether and S1R and S1S together when switched on You can replace the switch with two wire links but I do recommend that a switch be fitted so the socket doesn t have to take the full surge current wh...

Page 12: ...sense to look at grounding your modular cases together A 4mm banana socket being used as a common grounding point for a rack power supply Here the banana socket is connected directly with a nice thick...

Page 13: ...pplies together with a banana patch lead The nice thing about bananas is that they are stackable so it s easy even if you have more than two PSUs to connect up I recommend that you use thick multistra...

Page 14: ...han that included here will be provided by myself or Paul Darlow regarding the construction of mains powered items The mains transformer s secondaries should be rated 18 0 18 0 or 18 0 18 80VA This wi...

Page 15: ...re only a guidance and it is up to the reader to establish the exact obligations required in their own country It is essential that everything you build that has both live mains inside and a metal cas...

Page 16: ...ou will also need to provide earthing to any exposed transformer core This does not apply normally to toroidal types but EI types should have their metal frame earthed It is possible that by earthing...

Page 17: ...Mains wiring diagram For experienced builders only 17...

Page 18: ...point and is correctly called 0V or module ground This is the same as the MOTM ground The second ground is on pin 3 This is also connected to the power supply s ground But this ground is connected onl...

Page 19: ...ow and I are on this group as well as many other users and builders of Oakley modules If you have a comment about this user manual or have a found a mistake in it then please do let me know Last but n...