I lost my power supply and have to use my MF101 tonight. I know its 110V 5W input 9V output, but what are the milli amps? Has anyone used any other adapter?
Thanks
Andy
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ooops. This probably should go the the moogerfooger forum.
MoogerFooger power supply.
I laugh when people pay, say, $30 for an adaptor. I don't know what the story is in the States, but here in NZ it's ridiculous.
Now any EE feel free to correct me, but I am quite sure that the current on the adaptor does NOT have to be e.g 200mA "coz that's what the pedal says." Ohm's Law tells us that the higher the voltage, the higher the current will be drawn. So, it is only nesassary to use a regulated voltage (and polarity), especially with digital ones (e.g Boss DD-3 doesn't work with an unregulated supply).
And Moog pedals don't require regulation, as long as the voltage does not go past 15VDC, as that is the extent of the current limiting.
Power adaptors can be thought of as resovoirs; the higher the current, the bigger the resovoir. If you use more current than can be supplied, i.e empty the resovoir , then the power begins to be drawn from the mains supply and you get a lovely 50 Hz hum coming through your gear
I'm going for a 5 amp switchmode supply (yes, 5000mA) to power all my effects with hopefully low noise and more consistent voltage.
Now any EE feel free to correct me, but I am quite sure that the current on the adaptor does NOT have to be e.g 200mA "coz that's what the pedal says." Ohm's Law tells us that the higher the voltage, the higher the current will be drawn. So, it is only nesassary to use a regulated voltage (and polarity), especially with digital ones (e.g Boss DD-3 doesn't work with an unregulated supply).
And Moog pedals don't require regulation, as long as the voltage does not go past 15VDC, as that is the extent of the current limiting.
Power adaptors can be thought of as resovoirs; the higher the current, the bigger the resovoir. If you use more current than can be supplied, i.e empty the resovoir , then the power begins to be drawn from the mains supply and you get a lovely 50 Hz hum coming through your gear
I'm going for a 5 amp switchmode supply (yes, 5000mA) to power all my effects with hopefully low noise and more consistent voltage.
You should select an adaptor that supplies a MINIMUM of 200mA.basssfx wrote:Now any EE feel free to correct me, but I am quite sure that the current on the adaptor does NOT have to be e.g 200mA "coz that's what the pedal says."
You misinterpret Ohm's law with relation to power supplies. Your interpretation is correct for a load, but not for a power supply. If your power supply provides a higher voltage than is needed, the current draw is the same. The difference is that the regulator now has a higher voltage drop (Thevenin's theorem, not Ohm's Law) which translates into more power dissipated by the regulating transistor, which means more heat.Ohm's Law tells us that the higher the voltage, the higher the current will be drawn. So, it is only nesassary to use a regulated voltage (and polarity), especially with digital ones (e.g Boss DD-3 doesn't work with an unregulated supply).
Going past 15VDC has nothing to do with current limiting. It affects the power dissipated by the regulator components, which has a maximum. Higher power is higher heat, and that shortens the life of the components. Heat is the destructive enemy of electronics.And Moog pedals don't require regulation, as long as the voltage does not go past 15VDC, as that is the extent of the current limiting.
Depends on the design of the adaptor. If the regulator circuit has current limiting, excess current will cause the voltage to fall under its regulated value. It's a safety feature to prevent castastrophic failure. An unregulated supply that has excessive current draw means that the rectifier caps are discharging too fast and will indeed approximate the line frequency (50hz or 60hz) of your line AC.Power adaptors can be thought of as resovoirs; the higher the current, the bigger the resovoir. If you use more current than can be supplied, i.e empty the resovoir , then the power begins to be drawn from the mains supply and you get a lovely 50 Hz hum coming through your gear
Cheers MC, I did ask for it, didn't I? 
I personally always use regulated supplies.
I guess I was saying that people read 200mA (sometimes expressed as a MAXIMUM (!!!)) and go and buy their Boss adaptor.
I use, of all things, an old Sega Master System 9VDC adaptor with a heatsunk LM series reg and a smoothing cap. It does the trick suprisingly well, with plenty of current.
If you have the time, I was wondering if you could perhaps give some advice on the following setup:
As I mentioned, I would like one supply for as much of my gear as possible. I was thinking of using the following:
http://www.jaycar.co.nz/productView.asp ... BCATID=647
with a 5A 9VDC regulator (LM338K +3-35V).
Do you think this will be suitable for audio?
Thanks!!!
Keep rockin'!
I personally always use regulated supplies.
I guess I was saying that people read 200mA (sometimes expressed as a MAXIMUM (!!!)) and go and buy their Boss adaptor.
I use, of all things, an old Sega Master System 9VDC adaptor with a heatsunk LM series reg and a smoothing cap. It does the trick suprisingly well, with plenty of current.
If you have the time, I was wondering if you could perhaps give some advice on the following setup:
As I mentioned, I would like one supply for as much of my gear as possible. I was thinking of using the following:
http://www.jaycar.co.nz/productView.asp ... BCATID=647
with a 5A 9VDC regulator (LM338K +3-35V).
Do you think this will be suitable for audio?
Thanks!!!
Keep rockin'!