Everything about the Clavia Nord Modular G2, G1, and Micromodular Synthesizers.

Loose wire link in my G2... Is this normal?

Postby guytaylor » 04 Jan 2014, 03:08

Hi,
I opened up mu G2 to clean dust out and noticed something a bit strange.
There appears to be a wire link connected U26 (pin 14) to R26, but on my G2 the wire link is not soldered on any more at one end, it 'floating' next to it.

Here is a photo:

http://i1359.photobucket.com/albums/q78 ... 1b6b9d.jpg

The wire connects from point A to point B, but noticed how it is not actually attached at B...

Is this normal? or it a hack someone put in?
Should I resolder it?

Thank you very much
Guy
guytaylor
 
Posts: 3
Joined: 04 Jan 2014, 03:05
Country: Australia
Has thanked: 3 times
Been thanked: 0 time
Your Nord Gear #1: Nord Modular

Loose wire link in my G2... Is this normal?


Sponsor
 

Re: Loose wire link in my G2... Is this normal?

Postby mjbrands » 04 Jan 2014, 04:58

Interesting.

The chip the wire is attached to is a Schmitt trigger with six channels; it pretty much just cleans up a noisy electrical input signal - think MIDI, buttons, etc. However, the pin the wire is attached to is the power supply (Vcc), which is at +5 volts in this case. Likely the only reason this chip is involved is that someone wanted a source of +5 volts. It is possible that the PCB trace to the Vcc pin on that chip is damaged (or otherwise less than ideal), but then I would think the wire wouldn't be going to R26.

The big chip on the left is likely the Freescale (Motorola) ColdFire micro controller (MCU) that controls all the hardware (like the DSPs) in the G2, scans the keyboard and buttons, handles MIDI, etc. R26 is an SMD resistor and the marking 1002 means it is a 10k Ω resistor (first three digits x 10^last digit so 100 x 10^2 = 10,000). This is likely a pull up (or down) resistor for a floating in- or output on the MCU (ColdFire).

If R26 is connected to an input (on the left side), one goal may have been to prevent that input from ever seeing a low signal by connecting +5v directly to it. If R26 is indeed a pull up resistor (and the contact on the right is also always at +5 volts), they could also have replaced R26 with some solder (to create a bridge). If R26 is connected to a pin that is used as an output, I see two options; if the right contact on R26 is at +5 volts, then the pin R26 is connected to a current sink that tries to pull the signal low or if the right contact on R26 is at 0 volt, it is likely a current source.

To summarize this bla bla, I can say I think that the chip is an 'innocent bystander' and that R26 is either connected to an in- or output. The question is: what?

I think it is best to cover the bare end (b) with some tape for now, so it cannot touch anything else in there and put +5 volts on it which might even cause a short circuit (hopefully the fuse would pop before that happens though). This may be some kind of factory mod that came loose, but I don't expect it to be because I would've expected it to be done in a more proper way that doesn't put any mechanical stress on the solder joints (i.e. by affixing the wire to the PCB or some sturdy component with some glue).

If it turns out it is indeed some custom mod someone did, I would personally just snip off the wire near point A and not even desolder it.

I think you should take care of that bare wire end, but since it otherwise seems to be working fine, don't mess with it any further. :lol:
Last edited by mjbrands on 04 Jan 2014, 04:58, edited 1 time in total.
mjbrands
 

Re: Loose wire link in my G2... Is this normal?

Postby Mr_-G- » 04 Jan 2014, 16:08

Look what I found!
http://www.sequencer.de/pix/clavia/g2_unexpanded.jpg
I think that on the right of the image you can see the cable going from the chip to that resistor too... (unless the photo was of your own synth! :D )

The author Mr_-G- was thanked by:
guytaylor
User avatar
Mr_-G-
Moderator
 
Posts: 4610
Joined: 18 Aug 2012, 16:48
Has thanked: 1471 times
Been thanked: 1253 times
Your Nord Gear #1: Nord Stage 2

Re: Loose wire link in my G2... Is this normal?

Postby mjbrands » 04 Jan 2014, 22:50

Nice find! Looks like some factory mod then. I wonder what it is supposed to fix/help.
mjbrands
 

Re: Loose wire link in my G2... Is this normal?

Postby guytaylor » 06 Jan 2014, 01:38

Thanks for the feedback and great find!
Not Im not sure whether just to leave it disconnected or not...
("If it ain't broke, don't fix it" is ringing in my head!!)
guytaylor
 
Posts: 3
Joined: 04 Jan 2014, 03:05
Country: Australia
Has thanked: 3 times
Been thanked: 0 time
Your Nord Gear #1: Nord Modular

Re: Loose wire link in my G2... Is this normal?

Postby mjbrands » 06 Jan 2014, 02:43

I think you should at least do something about that bare end on that wire, because as it is now there is a small risk it will cause damage when it touches some of the other electronics. I suggest cutting off the bare end (include maybe 1-2 mm of insulation when cutting it off).
mjbrands
 

Re: Loose wire link in my G2... Is this normal?

Postby guytaylor » 06 Jan 2014, 02:57

Hi, Ok, I'll do that. good idea. :)
guytaylor
 
Posts: 3
Joined: 04 Jan 2014, 03:05
Country: Australia
Has thanked: 3 times
Been thanked: 0 time
Your Nord Gear #1: Nord Modular

Re: Loose wire link in my G2... Is this normal?

Postby Mr_-G- » 06 Jan 2014, 09:59

Ask Pablo Mastodon if he has an informed suggestion ;)
User avatar
Mr_-G-
Moderator
 
Posts: 4610
Joined: 18 Aug 2012, 16:48
Has thanked: 1471 times
Been thanked: 1253 times
Your Nord Gear #1: Nord Stage 2

Re: Loose wire link in my G2... Is this normal?

Postby cilek » 22 Jul 2014, 17:27

I think it might be covering for some damage they might’ve faced in some of their PCBs of internal track breakages. However, it’s not a very good practice to leave it just exposed like that. It could easily damage if there was a mechanical shock while it was switched on. Anyways, covering it would be wise. You can also launch an official complaint about this if you want to.
cilek
 
Posts: 1
Joined: 21 Jul 2014, 23:26
Has thanked: 0 time
Been thanked: 0 time


Return to Nord Modular Forum



Who is online

Users browsing this forum: No registered users and 10 guests