Inverter Questions

Careful with fuses, there are different ratings required for the different models that go to different regions (Jap/US/Euro).

There are also different ratings required between the different models (MPC60 is different to MPC60II is different to MPC3000) for some of the fuses even if they are the same region.

On the board near the blowed fuse i can read "125V 1.6A", so only a new fuse with the same reference is ok, or there are alternatives?

Don't get a "Slow Blow" fuse...
http://en.wikipedia.org/wiki/Fuse_(electrical)#Speed

SDC wrote:On the board near the blowed fuse i can read "125V 1.6A", so only a new fuse with the same reference is ok, or there are alternatives?

As long as the amperage is the same as what is specified, and the voltage rating of the fuse is equal or higher than what is specified, then it is OK.

You could use a 250V 1.6A fuse as a substitute, but not a 32V 1.6A fuse, for example.

The voltage rating is the maximum voltage that the fuse should operate at, a 250V 1.6A fuse will still blow at 1.6A whether in a 250V or a 125V circuit.

If you put a lower voltage rated fuse in to a higher voltage circuit, then it might still arc across the internal parts of the fuse when blown, since the fuse was not designed to handle the higher voltages, and not provide the required protection.

SimonInAustralia wrote:

SDC wrote:On the board near the blowed fuse i can read "125V 1.6A", so only a new fuse with the same reference is ok, or there are alternatives?

As long as the amperage is the same as what is specified, and the voltage rating of the fuse is equal or higher than what is specified, then it is OK.

You could use a 250V 1.6A fuse as a substitute, but not a 32V 1.6A fuse, for example.

The voltage rating is the maximum voltage that the fuse should operate at, a 250V 1.6A fuse will still blow at 1.6A whether in a 250V or a 125V circuit.

If you put a lower voltage rated fuse in to a higher voltage circuit, then it might still arc across the internal parts of the fuse when blown, since the fuse was not designed to handle the higher voltages, and not provide the required protection.

Copy that, thank you sir!

It's alive!!
Got a fuse from an old amp, and the MPC is working. Feels good

There's some kind of constant hum though - is it normal?

SDC wrote:
There's some kind of constant hum though - is it normal?

no, but it can be a common problem depending on what type of hum you are talking about... can you elaborate on that a bit?

Constant hum doesn't sound normal.

Are you running on an external stepdown transformer, to get it to work at your local mains voltage?

Is the 110V MPC Mains cable/plug using a 2 pin plug, without a 3rd ground pin?

If so, might be something to do with that? Not really sure how they operate when connected to a mixer while operating on a stepdown transformer through a 2 pin mains plug, in terms of ground and ground loop type hum issues.

How about if you just plug it in to the power, without anything else connected at all except headphones, maybe press record-play to start the sequencer recording to give you a metronome sound output to make sure you are getting audio out OK, do you get a hum then?

mr_debauch wrote:

SDC wrote:
There's some kind of constant hum though - is it normal?

no, but it can be a common problem depending on what type of hum you are talking about... can you elaborate on that a bit?

The noise comes from the power supply, and the cable i have has 3 plugs
Could it be my power stepdown?

MPC:
AC120V 60HZ~32W

Power Stepdown:
Input: 230V/50HZ
Output: AC110V 100VA

Are you talking about a hum from the speakers... or from the machine itself?

mr_debauch wrote:Are you talking about a hum from the speakers... or from the machine itself?

From the machine. I didn't connect any audio cable yet

Sorry, I thought you meant from the audio outputs.

Might be the LCD backlight inverter, a silver box on a small separate PCB just behind the floppy drive? It should have a thin 2 pin cable coming from the power supply, and another 2 pin cable going to the LCD backlight.

Maybe try powering it up with the cable from the power supply to the inverter disconected, to see if the noise goes away when the inverter is not powered?

After some close inspection, there's noise coming from 2 places. The higher and kind of high frequency noise comes from somewhere around the floppy drive.
Then there's more of a low frequency noise, not so loud, from the power suplly.

Any ideas?

well Im leaning towards simon's idea for the inverter... I doubt it's the floppy drive itself.

The buzz coming from the power supply could be a faulty component maybe?

SimonInAustralia wrote:
Maybe try powering it up with the cable from the power supply to the inverter disconected, to see if the noise goes away when the inverter is not powered?

I am not understanding this bit, can you elaborate?

Just realize that my power stepdown is making noise by itself, even with any device getting power through it. When i connect the MPC the power suply makes some noise, but not much - i guess it's normal.

But the other noise around the floppy still here. I will try to record a video