Author Topic: A Shocking Experience Again. (Read 564 times)

lbpesq · « **Reply #15 on:** January 28, 2009, 07:27:33 AM »

Isn't that what the standby switch on the amp is for?

Bill, tgo

olieoliver · « **Reply #16 on:** January 28, 2009, 07:00:27 PM »

OK, I figured it out. (I think).

Not being one to enjoy getting a good shock, having 3 near death experiences with electricity but that?s another story, I had to convince myself to reproduce the whole shocking experience.
SOoooo to do this I had to convince myself that it wasn?t going to hurt. (I can?t find my multi tester so my thumb needed to do.) I kept telling myself all day at work, it won?t hurt, it?s going to uh ...tickle, yea that?s the ticket, it will tickle.
So I get home and decide to try a couple of test tickles, and you know what I found out? My test tickles HURT. ZZZZZappp.

But seriously I got out my little test light and found the culprit. In the photo below the arrows point to the 2 outer pins (I assume are ground??) anyway when I pulled the cable out from the bass, the inner 5 pins of the bass were still making contact with the female pins in the cable. But my thumb made contact with these ?outer? pins and the outer case of the 5 pin socket on the bass, I assume my thumb completed the circuit, and ZZzzzaaa-aaap. No big deal I just need to switch basses a little slower nest time and watch my thumb.

OO

David Houck · « **Reply #17 on:** January 28, 2009, 07:16:17 PM »

Thank you for sacrificing yourself in the interest of science.

elwoodblue · « **Reply #18 on:** January 28, 2009, 07:48:30 PM »

My grandpa use to test 110V with his thumb and forefinger ( he was a line man in the 40's)...I'm glad they've made progress in electrical testers.

I'm glad you figured out the mystery Olie.

JimmyJ · « **Reply #19 on:** January 28, 2009, 08:47:43 PM »

OO,

Well done and very brave! When I was a kid I built a variable power supply out of a wire-wound rheostat, a volt meter, an AC receptacle and an extension cord. Amazing I didn't kill myself...

There is still something amiss here. What your painful test implies is that pin-1 (ground) is not making the proper contact between plug and jack. The female side of our plugs and jacks are designed so that pin-1 is the first to connect when inserting and the last to disconnect when unplugging. So at no time should the + and - voltage be live when the ground circuit is disconnected. By your decription the ground circuit is being completed only through the physical shells of the plug and jack making contact - or through your thumb. Ow!

Open both the plug and the bass and make sure pin-1 connections are sound. If all looks proper it could just be a worn out female plug and time to invest in a new cable.

Good luck!
Jimmy J

David Houck · « **Reply #20 on:** January 28, 2009, 09:05:10 PM »

Great diagnosis Jimmy! Olie; have you tried another cable?

mica · « **Reply #21 on:** January 28, 2009, 09:20:15 PM »

Where you are touching should not shock you at all.

Let's test the DS-5R rackmounted power supply. Set it up like usual and plug the 5-pin cable in your DS-5R. Find your voltmeter (or get a cheap one at Radio Shack) and put one probe at the contact shown at the red arrow in your picture, and hold the other probe in your hand with the multimeter set on AC volts and you shouldn't see very much.

You can safely do the same thing with the DS-5. Are the readings different? If so, send that DS-5 back here pronto - you are getting shocked from the wall current, not from the DC that normally powers the bass.

If the reading are similarly low, there's potentially a problem somewhere else (power amp, outlet strip, wiring in the wall) that is serious. Please be careful and report back to me.

terryc · « **Reply #22 on:** January 29, 2009, 01:39:03 AM »

olieoliver..I would take mica's advice strongly and get a multimeter and send the PS back to them for analysis.
As a part time electrician I have seen & felt far too many faults and we have 240V AC here in the UK so we are extra careful...110V pah! a walk in the park!
Seriously though get it sorted for your own & family's sake

olieoliver · « **Reply #23 on:** January 29, 2009, 07:03:02 AM »

OK, first off I DID NOT use my thumb, I may have been born at night but NOT last night. LOL

Since I couldn't find my multi-tester I used a automotive 12 volt test light. I plugged the cable into the DS-5 and connected my test light to the terminals shown. I do get current there and it is not much for it illuminated the light but did not blow it. SO if it where anything more than 20 volts it would have blown the blub.

And Jimmy pin 1 on my cable is the last thing to make contact. I can pull the plug slightly out of the bass and see pins 1 and the others (pin 2....)are making contact.

When I get home tonight I'll post a photo that should clear this up.

I guess now my question is should there be NOthing at pin1? Is it NOT the ground or...?

Honestly I don't think there is anything wrong with the bass, DS-5 or cable. Just one of those condition things. My hand was wet from sweat, my thumb came into contact in a place it should not and there ya go.

I will try what you suggested Mica tonight.

NO Worries

OO

terryc · « **Reply #24 on:** January 29, 2009, 07:28:54 AM »

Just to change the subject(and show my ignorance) since I only own a MK which takes a single 9V battery.
Do you have to plug the bass into your amp via the 1/4 socket as well as have this power cable plugged in or is this cable split with a separate line to the amp...I have never seen this at all.
Mark King used batteries I believe on his S2 as he used a radio system.
Pics would be useful..anyone!

jacko · « **Reply #25 on:** January 29, 2009, 07:35:06 AM »

Nope. One cable for the power and stereo signal but it has to go into the DS-5. From there, you can either use 2 1/4 leads into a stereo amp/ two amps or a single 1/4 from the ds-5 passing full range into a single amp (the DS-5 works out what you've done).
As an alternative, you can use a 1/4 inch cable from the instrument to get a mono signal as per the signature etc electronics although I believe earlier series instruments only had one of the pickups signals into the 1/4 socket.

graeme

terryc · « **Reply #26 on:** January 29, 2009, 08:13:42 AM »

Thank you jacko for putting me right on that one.
Seems like a good system although I read that the Ox got right pissed off with it and stopped using Alembics, it was at the Live Aid gig 20 odd years ago.

JimmyJ · « **Reply #27 on:** January 29, 2009, 10:03:30 AM »

Double O,

The mystery continues! Sorry I wasn't totally clear... You wrote:
...pin 1 on my cable is the last thing to make contact. I can pull the plug slightly out of the bass and see pins 1 and the others (pin 2....)are making contact.

But here's the thing... The points on the plug which you have red arrows pointing to are not pins. Those points ARE meant to make an electrical connection between plug and jack, but only really to extend the shield or screen as the cable enters the instrument. There is not meant to be any voltage potential there. As you observe, the shells of the jack and plug are the last to connect.

Take a look at the attached pic below. (I know, it's a panel jack but the pin configuration is the same as on your female plug.) If the face of this jack was a clock, at um, 2:30 you will find pin-1. In our instruments THAT is meant to be the primary ground connection. Also notice on this pic that this is the only hole that you can see a little of the metal contact showing. That is how the plug is built to connect pin-1 first! Cool, huh?

Now the next problem... You said you lit up a 12v bulb between the two points you've marked. Are you SURE you weren't testing between the shell and the other side of your plug? You see, pin-2 (about 4 o'cock on the pic) is not one of the power conductors. Power is running on pin-4 and pin-5, the other side of the plug face (8 o'clock and ... 9:30). Again, the voltage here should be about +18 to ground on pin-4 and -18 ground on pin-5. Your 12 volt bulb would have lit quite brightly when attached to the shell of the plug (red arrows) and either pin-4 or pin-5. But not pin-2...

I'm still voting for a disconnected pin-1 on the plug or the bass causing any current going to ground to travel through the shells of the two connectors. Not what's supposed to happen! Take some more readings - can you take a photo of the inside of the plug? Be careful not to short out things when it's powered up!

Double J

olieoliver · « **Reply #28 on:** January 29, 2009, 10:19:45 AM »

Thanks JJ, I will try that tonight. You are probably correct about which pins I got current thru.
After I look tonight I will check back in.

Thanks,
OO

pace · « **Reply #29 on:** January 29, 2009, 10:39:58 AM »

I didn't realize that DS-5 peak to peak was 36V.... I always assumed that it was +9V / -9V, and corresponded directly to the 2 batteries in the cavity....

unless of course Ron built Jimmy an extra special SII....