Battarypack Electribe EMX

gmeredith · Post by **gmeredith** » Thu May 15, 2008 2:52 am

BTW graham, I did take resistance measurements for the wires earlier today, but neglected to mention them in my post because all the pins registered 0 ohms resistance relative to any other pin.

I thought of that after I posted - I realised that the transformer coils may have a low resistance (a few ohms or less), and may appear to be ZERO with a meter that was not so sensitive. They may perhaps show a difference with a sensitive enough meter. Although it doesn't really matter, now

So, graham, why would korg use an AC power supply just to do a shitty AC-DC conversion inside the x-tribe? Seems like a waste of energy to me

Manufacturers will always try and cut the price of maufacturing where they can. It's my guess that it's much cheaper for a company to order a million generic 10V AC transformers with no other guts in them but the transformer coils, and then build the regulation circuit onto the one whole EMX PCB that a production line robot can do very cheaply, instead of having to design and build 1 million separate regulator circuit boards and install them in the power pack or buy specially made DC power packs from another manufacturer.

Alesis were one of the first companies to go down this line. They designed equipment so that as much as possible was built directly onto the PCB, so they could cut down production costs and therefore undercut competitors with the shop price. Quite clever, really. But very annoying, for hackers like us

Cheers, graham

Ruso · Post by **Ruso** » Thu May 15, 2008 3:03 am

I might not know about building circuits, but I have the schematics for a reason and I'm not a complete idiot. I have decent experience with microcontrollers which is directly related to electrical enginering... this is what I was talking about when I told you I have experience in similar areas.

The plan was to flash the main controller with my own code but it was too much work to rewrite communications between all the parts... the io board's design is a mess. I could probably figure it out but it would involve too much reverse enginering which would take too long. I fugured I'd b e better off building my own.

You don't need to be an electrical enginer or know how the machine's parts work together. If you still think I'm dumb then you're nothing different except you're more of an electritian nerd.

Dumb ass? No... why should I share schematics with you when I told that it works? It's not my fault you don't believe me. That's your problem, it's not my problem of not sharing it.

I've had full schematics for the electribes for months and I've mentioned them on this board multiples of times... if you cared about them or this board and saw that you would have known that.

results of circuit bending were not significant enough to continue, there are almost no analogue parts in the machine(I realised this after looking at schematics)......

I got some stuff to conflict, buz, squeel but nothing usable.

I'm going to ask you one more time are we going to be civil and get along or are you going to continue being a jack ass and insult/underestimate me in public?

MagpieIndustries · Post by **MagpieIndustries** » Thu May 15, 2008 8:49 pm

Ruso wrote:I've had full schematics for the electribes for months

Show us, or shut the f*ck up Ruso

808state · Post by **808state** » Thu May 15, 2008 10:00 pm

http://www.youtube.com/watch?v=OeccfxScPH4

watch that,go on.

Ruso · Post by **Ruso** » Thu May 15, 2008 10:01 pm

ya but it's got no tubes, that's the thing we're discussing at this point.

Service Manual:
http://www.audio-ruso.com/EMX-Srvc.Man.zip

you get what you ask for, and how you ask for it.

808state · Post by **808state** » Thu May 15, 2008 10:08 pm

okay,my mistake.The EMX will require more juice....possibly a bigger Li-Ion battery would do the job.like the one in that vid i posted.

It could prove very awkward at that stage,it all depends on how far you want to go with it.The sheer novelty of having a "portable" emx is what it comes down to.

But other wise,the Li-Ion is your best bet,or a big Nickel metal Hydride battery too,that would be suitable.Charge it up and away you go,they would HAVE to be available somewhere on the the ol' interweb.

And aswell as that,you would have to alter the connection coming out of the battery,ie.: you would need an adapter like...because the battery would most likely NOT go straight into the AC in of the EMX (and ESX yeah?)

808state · Post by **808state** » Thu May 15, 2008 10:11 pm

Its a great idea all the same,but you would never be allowed on a plane with all that stuff,not a hope in hell.

Great if you were goin' busking with a big battery powered amp on the streets in town!

Ruso · Post by **Ruso** » Thu May 15, 2008 10:34 pm

808state wrote:Its a great idea all the same,but you would never be allowed on a plane with all that stuff,not a hope in hell.

Great if you were goin' busking with a big battery powered amp on the streets in town!

khehe I got a 9 volt amp that runs a set of speakers about the size of studio monitors. This is the reason I'm doing this battery pack acutally

Borg · Post by **Borg** » Fri May 16, 2008 2:23 am

It's great that we are starting to come closer to the solution here and that more and more people start getting involved!

But because of the hot-headed exchange of words here, two of my posts remain unanswered. I'd really like them answered, so here they are again:

I wrote:So, if it's possible to drive the machine on batteries, here's a list of components I think I'd need for the battery:

4-pack rechargeable HR6 CoTech batteries (1,2V/2500 mAh) 2 pcs

Battery container for eight batteries

Battery contact

1m/3.3ft midi cable

TOTAL COST: 368.00 SEK = $61 USD (according to XE.com)

Eight HR6 batteries will give me: 1,2V*8 = 9,6V and 2500 mAh*8 = 20 000 mAh if I connect them in series.

How 'bout this? Would it work?

I wrote:So I've got this in mind. It's on 9,6V and 2000 mAh. Only thing is that it's a "transmitter battery". On the site they sell bot transmitter and reciever batteries, as well as just batteries.
I have no idea what the difference is or if it matters in this case.

But if I hooked a couple of these up in parallel, do the capacity increase? Is this the easiest way of doing it?

Which one of these two alternatives would you suggest? Would they even work?

gmeredith · Post by **gmeredith** » Fri May 16, 2008 6:57 am

Hi Borg,

I just spent about 1 hour typing you a reply, with lots of good details, only to find when I hit "submit" my login time had expired and I lost all of the text

I basically was saying that you might try ordering a few extra cells, in case you found 9.6V didn't power it very well. I recommend 10 cells (12V). Then you would already have them there, rather than have to order them again before you could use it. They will also give you a bit more voltage headroom, and you'll get a longer run time out of the pack before needing to recharge it. Other than that, they look like good batteries, and the price is good.

I also would say, though, that to be sure, you should try and run it off a 12V or 15V DC adapter first (1000-1500mAH), just to establish that you can get it to work off DC. Then you can do measurements, like how I described in a previous post. You're going to need the DC plug pack for charging the batteries anyway, so you may as well get this first.

If you measure the DC current draw, then you can know exactly what size mAH batteries will run it for X amount of hours.

Eight HR6 batteries will give me: 1,2V*8 = 9,6V and 2500 mAh*8 = 20 000 mAh if I connect them in series

Your mAH for your pack will still only be 2500mAH, I'm sorry to say. When you add batteries in series, the voltage adds, but the current stays the same. When you add them in parallel, the voltage stays the same, but the current adds together.

But I still think a 2500mAH pack will run them OK. If anyone DOES measure the DC current draw, I will then be able to tell you how long a certain mAH battery will run the EMX for, and you can know what to buy, depending on the run time you want

But if I hooked a couple of these up in parallel, do the capacity increase? Is this the easiest way of doing it?

Yes, that's correct. You would double your capacity (but your voltage would stiil be 9.6V).

I have some of those type of battery packs. They're to fit inside the hand controller transmitter of a model R/C car or airplane. They are exactly the same individual batteries inside the pack as your loose cells, just in a plastic casing. The only trouble with these pre-made battery packs is that you can't add extra cells if you find 9.6V is not enough.

I would go with the loose batteries as per your first example, and make your own pack. You have more flexible options, then. And you could STILL make up a 2nd pack and add in parallel, like those ones, anyway, but you could make them 12V packs instead.

Cheers, Graham

Borg · Post by **Borg** » Sat May 17, 2008 1:10 am

Oooh, I know all to well how that feels like.

But know I've trained myself to instinctively copy all text I write on various forums and webpages before I post it, just to be safe.

gmeredith wrote:I recommend 10 cells (12V). Then you would already have them there, rather than have to order them again before you could use it. They will also give you a bit more voltage headroom, and you'll get a longer run time out of the pack before needing to recharge it. Other than that, they look like good batteries, and the price is good.

Alright, so the ESX (in my case, but doesn't really matter really) can take more than 9V? Not a problem to go for a 12 volter?

If you measure the DC current draw, then you can know exactly what size mAH batteries will run it for X amount of hours.

Eight HR6 batteries will give me: 1,2V*8 = 9,6V and 2500 mAh*8 = 20 000 mAh if I connect them in series

[quote:"gmeredith"]Your mAH for your pack will still only be 2500mAH, I'm sorry to say. When you add batteries in series, the voltage adds, but the current stays the same. When you add them in parallel, the voltage stays the same, but the current adds together.

But I still think a 2500mAH pack will run them OK. If anyone DOES measure the DC current draw, I will then be able to tell you how long a certain mAH battery will run the EMX for, and you can know what to buy, depending on the run time you want

[/quote]
Right. I don't have got any pssibilties of measuring that thing right now. Don't own any electronics gear. But I have some powerful friends...

Right now this project is still in its theoretical stage because of the lack of money. But as soon as I get enough I'm gonna put this thing together. And maybe we know excactly how to do it by then?

n3ldan · Post by **n3ldan** » Sat May 17, 2008 2:59 am

Yes, based on Ruso's schematic graham told us that it can take about 9~18v.
Voltage sag would cause the voltage to drop unusably low before all the power was drained in a 9v or 9.6v battery, so 12v gives you room for the voltage to sag and still be usable.
10 1.2v NiMH cells or 4 3.6v Li-Ion cells would work well, both are readily available in 2500mAh capacities.

If you choose NiMH I like this charger: http://www.amazon.com/Energizer-15-Minu ... B0000DIIAS

It uses a fan to cool the batteries and charges them very quickly. For ~$50 you can get a 15 minute 4 battery charger and 12 2200-2500mAh AA batteries.

That would certainly be simplest, just buy an 8 battery holder and a 2 battery holder and put them in series, connect that to the hacked midi cable and you've got a battery powered x-tribe

gmeredith · Post by **gmeredith** » Sat May 17, 2008 3:01 am

Alright, so the ESX (in my case, but doesn't really matter really) can take more than 9V? Not a problem to go for a 12 volter?

I don't see any reason why the ESX would be any different in this, seeing that it uses the same power supply as the other Xtribes. It should be fine for 12V. As Ruso has mentioned, he powered his EMX off a 15V DC power pack.

Voltage sag would cause the voltage to drop unusably low before all the power was drained in a 9v or 9.6v battery, so 12v gives you room for the voltage to sag and still be usable.

Yes, that was exactly some of the stuff I had wrote about just before the infamous forum post "time out" incident

You can pick up cheap 2nd hand DC power supplies from some junk shops, or 2nd hand computer shops. Many old printers, fax machines, modems and scanners use a DC 12 or 15V 1000-1500mA power pack (in fact, you might already have one without realising it in your computer setup somewhere. Or simply borrow one from someone that does). These would be ideal, if you could pick them up for $5 or so.

This is a type of example of what I mean:

http://www.jaycar.com.au/productView.as ... BCATID=521

If you could get that sort of thing 2nd hand, it would be ideal. But even new for $40 is OK, with that voltage adjuster switch it would also make an ideal charger for your battery packs - you could knock back the voltage a bit while charging, so you don't cook your battery packs when they reach full charge.

Right now this project is still in its theoretical stage because of the lack of money

Oh, don't I know THAT feeling

Cheers, Graham

Ruso · Post by **Ruso** » Sat May 17, 2008 3:12 am

beware, I just had my electribe run on 10.8 v on a really old lap top battery..... it powered up...

then I went out and bought a new lap top battery.... it fried the electribe. Gladly it was a single small component and not the rest of the tribe...

the mistake: I powered it up with a 10.8b 4500mah lap top battery....

too much power. (the idea was to power two electribes at once but I couldn't resist testing it out on one.

so now I'm digging through the damn service manual schematics to find the little part I fried which at this point is quite unrecognizable.

gmeredith · Post by **gmeredith** » Sat May 17, 2008 3:21 am

Oh - OK. Hmmm... - perhaps more reason to stick with only 2500mAH batteries. And start with a 10.8V pack (9x 1.2V batteries). Ruso - do you think it was the fuse that blew?? - apparently the early X-tribes were recalled because the fuses in them were too low a rating and they were all blowing after a while for no reason at all. Korg said they would put a heavier size fuse in them at no cost...

When you originally tested it on the 15V DC power supply, do you remember its mA rating? Obviously 15V DC didn't kill it then, so perhaps we could find out what current it supplied without blowing it.

Cheers, graham

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