Korg Forums

[gmeredith]

So somewhere there was a short - if all you got was about 1 volts when hooked up, which explains why the power pack fried.

Make sure that your board is the same as mine in my guide before you hook it up to those points - I'm not sure what differences there are in the EM1 to the ES1 board. It still should be easy, just maybe slightly different.

Try this test first. Disconnect all of your battery packs and socket from the EM1. Plug in your EM1 power pack in its normal power socket as you would normally run it and switch it on. Now, while the EM1 is switched on, test those battery connection points with the meter and measure the voltage. You should get 9-10v or something. If you don't, they are not the correct connection points. When you do find the correct points, these are where the battery pack wires should go, with the + battery wire going where the meter probe read +10V.

Cheers and good luck.

Graham

[zalo]

when i have it plugged in i get the full voltage at those connection points

there seems to be something on the battery side of diagram

the connection points are the same on both boards

the pattern is different but the circuit paths are the same

im going to solder the batteries to the circuit board see if that does it

[zalo]

[gmeredith]

Let me know how it goes!

Cheers, Graham

[zalo]

i let the battery pack charge for 20+ hours and when i turned it on it only lasted like 1 minute

so i guess its time to start over again and figure this out

i get power from the battery when i test it but it doesnt last

[gmeredith]

OK, this is a start though, that you've got it to run off the batteries. What are the specs for your new multi-voltage power pack (ie. voltage choices, mA rating)?

After you charge the pack, what is the measured voltage of the pack? It should be at least 9.6V (and will probably be around 10V or over with some charge in them). If it's not (like less than 9V) then there's something wrong with the pack still. (In this case, I'm talking about each pack being made up of 8 gumstick batteries in series = 9.6V - which is how I assumed you wired it.)

Measure each battery in the pack (just put the meter probes on the ends of each battery - it won't affect the measurement if the batteries are still wired together). Each battery should be about 1.3V. If one of them shows less than 0.5V then it may be a dud and dragging down the voltage of the overall pack. And make sure of the obvious - that one of the batteries isn't wired in the wrong way in the pack accidentally.

It may need to be charged on one of the higher voltage selections - like 9 or 12V. If you do set it to 12V make sure you watch over it to see how hot the charger gets. Don't let it get too hot or it will blow. If it gets hot rapidly knock it down to the next lower voltage selection.

Also bear in mind that you have a pretty big battery pack with all 16 batteries. They will take a while to charge, even at a higher charge rate.

Cheers, graham

[zalo]

9,10,11,12,13 800ma

11ish volts charged

i am only using 8 right now until i get it working well



edit

ok, i simplified everything

went from 10 solder points down to 5 (not including inside the battery packs)

and bam! the 1 battery pack stayed playing for 30 plus minutes as i resoldered the second battery pack

so i soldered the second pack in after i got it pumping juice by itself outside of the box

turned it all on after and it worked great

now im letting it charge

tomorrow im going to home depot to pick up the 4 screws from the back i lost in all of this and i will have a fully portable music writing station

im so excited you have no idea

things ive learned

1. sand down the negative posts of gumstick batteries to solder them (medium metal paper works perfect)
2. less solder points = less chances of screwing up

thanks for the help

i would never had done this with out you


edit 2

went to put the back plate on after charging and testing it again

put the back plate on and it turned off

took the back plate back off and now it wont turn back on at all

cant figure out what made it do that

still getting the 11vdc at the solder points

i have a feeling i some how just bricked it

[gmeredith]

That's really wierd. Try disconnecting the batteries and using the power pack only (on the 9V setting) in the normal EM1 power socket, to check if it works. If it does, I'd say one of your battery connections to the board is not so good. Or else your power switch is playing up. Hope it works out simple.

Cheers, graham

[zalo]

i tried that and still nothing

[gmeredith]

Bummer! Something must have moved or shorted when you put the back on it. Have you got the EM1 service manual? You can get it here if you don't:

http://launch.groups.yahoo.com/group/electribe/

It's in the FILES section on that site (you'll have to join the group as a member though, to access the files)


On p6 in the service manual is a diagram of the power supply rails in the EM1, if you need it.

But I would start elsewhere simpler first. Unhook the battery pack. Check your power pack still works - switch it on and put a meter across the plug. If ok, connect up the power pack to the EM1 as normal and switch it on (make sure it is set to 9V or less). Now use your meter (in Volts mode) and probe various points around the switch area to see where you get volts, both with the switch on and off. If you're getting volts where you would connect up the battery normally, when the power switch is on, and none when you switch it off, then the switch is obviously OK. If you get no volts either on or off, either the switch is faulty or there is something shorting out the power supply somewhere. If ok, test the voltages further down the line. The EM1 has 3 or 4 different voltage regulators for different parts of the circuit: +7V, +5V and 3.3V . You can track them and test their output voltages. If one of them is blown, it won't be putting out any volts.

Also, check carefully to see if any of the circuit tracks have lifted or been broken with all the soldering/unsoldering, and that there arent any loose stray blobs of solder bridging the tracks anywhere.

Hoping its ok, you are so close to getting it happening!!!

Cheers, Graham

[n3ldan]

So I finally got some AAAs and set down to do this.
There is significantly more room inside an ER-1 MKII; I built and tested a battery pack and it worked fine. ~10v "dead".

For 2 minutes, I had my battery powered bliss. Then I did EXACTLY what zalo did.

I put down the velcro on the back plate, tested it one last time, and put the plate back on. It turned off. The batteries were EXTREMELY hot. I took it off and quickly cut the battery leads. The resistance between the two parts of the barrel plug jack is now 0 ohms. I have lost all my favorite patterns and now I don't even have my electribe.


On the plus side both my wall warts still work (I was testing with a 300ma roland one because I thought it would me marginally safer). I get ~13v with it connected to nothing, then when I plug it in I get 0v at the solder points.


I would love it if you could point me in the direction of a service manual or places to check on the board. I would kill to revive this thing.

Thanks

[gmeredith]