someone know about power supplies and or voltage (sp555)

[timfromtexas]

i bought a sp555 used.

dood said he bought it used from guitar center. i wasnt too stoked on that but whatever it was a good price.

he had a roland adapter for it and i didnt think twice. im pretty sure its what guitar center sold him with the 555. the roland site says this about the 555

Power Supply
DC 9 V (AC Adaptor)
Current Draw
800 mA

mine says
dc 9 volt

but the current draw is 1000 ma

is that going to be an issue. im pretty positive that he has been using the same one for however long he has owned it. but i figured i would just see what you guys had to say.
bueno?

[cartesia]

that's fine.

the machine's current draw is 800ma

but the power supply *supplies* current - up to 1000ma.

so as long as you have at least as much as the device draws, you're ok.. the problems arise if the device tries to draw 800ma from say a 750ma power supply.. overheating/failure is quite possible.


The only other thing you need to check is the tip polarity:



There should be a picture on the back of the 555 or in the manual like that, and then there will either be a picture on the power supply or if it's a changeable-head power supply, the interchangeable plug will have the +/- lined up with the writing on the socket that says 'tip'

[timfromtexas]

cartesia thanks a ton. i found what you were talking about on the power supply and i looked on the 555 itself and couldnt find a symbol similar to the same one, and i also looked in the manual online and couldnt find that symbol there either. i found the info on the specifications on what the 555 will take but couldnt find the image. i DID plug it in the night i got it home and turned the machine on to be sure i didnt get burned by the sale and it worked fine. i just wanted to be sure that i was gonna set my apartment on fire much less burn out the machine itself. is the polarity stuff still worth digging into or should i be safe from here?

[formal]

If the polarity was the opposite it would not turn on. When you buy a universal AC adapter the tips are removable. So when you put it on and it doesn't turn on your just turn the tip around. This has never killed any of my machines before.

[timfromtexas]

yea i kinda figured that much. i just noticed the sticker on the bottom (donno if i mentioned it IS a roland power supply) says SPD-S.. one of those sample drum pad things. weird though.

[Headphones]

Since the sp555 is newish, getting a power adapter from Roland's website shouldn't be a problem if you don't trust the one it came with, and want the correct one it should have.

It's when your synth/drum machine/sampler is old and discontinued it gets a little more tricky to find the right power supply. But good luck to you. Check eBay, and you might get lucky on finding the correct one for cheap.

[V.ANDA.L.]

Yo I'm hopin someone on this thread can help me. I'm on a trip way away from home and I brought my 555 (super hyped that i was gonna be able to mess with
some vibes when i got there) and i got there to realize... that I didn't bring the adapter!!!

I happened to find an adapter lying around that fits into the 555 but I don't know, I don't want to turn it on until someone tells me it's fine. It's for a toy called leap frog lol... The adapter says:

Input:120VAC 60Hz
Output: 9VDC 700mA 6.3VA

and The Roland site lists
DC 9 V (AC Adaptor)
800 mA

I read everything on this thread but I still don't really get all the
input/output/draw stuff and how it works so any help is appreciated.
I'll try reading over everything again and see if I can wrap my head around it.
My assumption though is that I can't use it because the "draw" on the adapter
is less and the 555 needs more than that so it might overheat?...
Help please ASAP


thanks

[* warrika *]

If the polarity was the opposite it would not turn on. When you buy a universal AC adapter the tips are removable. So when you put it on and it doesn't turn on your just turn the tip around. This has never killed any of my machines before.

That's because a lot of devices have some protection, diodes and whatnot.

I fried a nice Arion Digital Chorus/Flanger by reversing the polarity, so it can happen, especially with a more powerful adapter.