A wiring question

[MPR]

Hi there. Quick history: I pulled the housing off of a couple of MIDI keyboards that are specifically designed to hook up to a personal computer, MIDI to USB. (I basically created my own housing so they'd fit my space better.)

Having said that, I ran into a problem - the circuit boards need to be positioned in an area that are too far for some wires to reach. Here's what they look like (see below):

A. Side view:
B. Top view
C. The area on the board the wire / cable plugs into (highlighted for clarity)

There's actually two questions:
1) What is this wire called? It's terrible that I ask a question about something I don't know the name of.
2) Since it cannot reach (to where I'd like it to go in relation to the keyboard), is there such a thing as an extension cord for this? That is, a male / female cord that I could extend this connection with?

Thanks for reading, any help would be appreciated!

 

[davenn]

hi there
welcome to the forum
no there aren't extension leads, you would have to make your own longer leads
the cable type is called ribbon cable
considering that those connectors are relatively hard to purchase and even more difficult for an in-experienced person to terminate.
One suggestion would be to cut the cable an inch or 2 out from the connector and solder in an appropriate length of cable to suit your needs, using heatshrink tubing to insulate the solder joints.
It will still be a fiddly job but it would have the desired effect for you.

Dave

 

[MPR]

After some research, it would appear that -- in order to make an extension cable for this -- I would need some 14-way ribbon cable, 1 male and 1 female DIN 41612 connector. The things I'm not sure about would be what type of connector, and how exactly the would attach to the ribbon cable.

I'm not sure if soldering is necessary.

 

[davenn]

After some research, it would appear that -- in order to make an extension cable for this -- I would need some 14-way ribbon cable, 1 male and 1 female DIN 41612 connector. The things I'm not sure about would be what type of connector, and how exactly the would attach to the ribbon cable.

I'm not sure if soldering is necessary.

for the type of connector shown, the cables are crimped onto the individual contacts

D

 

[(*steve*)]

...are crimped...

Probably using a special tool that costs a small fortune...

The crimp connections can vary from being really hard to almost impossible to make without the right tool.

 

[MPR]

How "special" could it be? Ribbon cable is used quite often in today's electronics.

Unless there are different types, I manged to find several that are under $25.

Sears
CWC

 

[(*steve*)]

Fine, but your connector is not an IDC connector.

These are not the right tools for your connector, but the prices are not atypical for crimping tools. It applies especially when you need to get a tool for an unusual connector, where you do not have the luxury of shopping around for various suppliers.

In the days when I had the large printed RS catalogue, I might find a nice connector, only to find that I would be paying $500 for the tool to terminate cables to it. If you have to terminate thousands of connections, fine. But if it's only one or two...

I'm not saying this WILL be the case. I'm saying that you should be prepared.

 

[MPR]

How can you be sure that the connections are not IDC? They certainly look like it.

 

[davenn]

How can you be sure that the connections are not IDC? They certainly look like it.

cuz I have worked on many of those connectors on a daily basis
they are used in mass in much modern electronic systems

the ones you linked to do a crimp across the whole connector in one action.
BUT, the connectors you are dealing with, each individual wire has to be individually crimped
before sliding into the plastic housing

this is an example of an insulation displacement connector....
http://en.wikipedia.org/wiki/File:Pin_1_idc.png

Dave

 

[MPR]

Thanks for that.

So do you know of any place I could get a male and female connection like what I have as well as some 14-way ribbon? I'm not afraid to solder, either. So long as I know what exactly to do.

 

[(*steve*)]

14 way ribbon is easy. Just get some ribbon cable with more than 14 wires and peel off the excess. In many cases you can use multiple lengths of cable with less than the number of connections you require (so 50 way made from 2 x 25 way).

If you can't get 14 way IDC connectors, then use something larger (and keyed) so that you can just use the last 14 connections of (say) a 20 way connector.

 

[MattyMatt]

in all technicality, you could use 14 of the same gauge wire, connected by any fashion you like... simply by cutting the connection down the center... now, whether this will negatively impact the performance of the device... I can't tell you, but in a situation like this, I would recommend a solder connection, and if you want to use a "connector" find a couple of nicely and VERY tightly mating connectors, and you should be good.

I have had to do many proprietary cable modifications over the years.... once you get the hang of it... it generally goes pretty well.

Just one rule to remember... with length, comes attenuation... which is generally, not a good thing.

 

[MPR]

If you can't get 14 way IDC connectors, then use something larger...

In an earlier post you stated that what I have is not IDC connectors. As with my earlier problem, I can't order something I don't know the name of.

Just one rule to remember... with length, comes attenuation...

The distance is extending by 10 inches at most. Considering your years of cable modifications, at what point do you see attenuation becoming visible?

 

[(*steve*)]

In an earlier post you stated that what I have is not IDC connectors. As with my earlier problem, I can't order something I don't know the name of.

Cut the existing cable, place male and female connectors either side of the bit, then make an extension (with the same male and female connectors) to extend it.

That way you don't need to know what the original connector is.

The distance is extending by 10 inches at most. Considering your years of cable modifications, at what point do you see attenuation becoming visible?

It depends on the signal and how long the cable is already, as well as losses in connectors.

If the cable is currently very short, and the signal frequency is very high, it may become noticeable quite quickly. Without an intimate knowledge of the device itself, this is a very hard question to answer with specificity.

 

[MattyMatt]

Yeah I would need to see some kind of specifications on what kind of signal is traveling down those little wires... there are some decent equations to figure out attenuation that aren't too hard to plug in numbers into... I'd have to find something appropriate, but 10 inches is probably not too much of a stretch... how long is it now?

 

[donkey]

i saw this post and thought of an alternative maybe. why not solder a small pcb with 2 female connectors on it... then you just have to find another ribbon cable that matches the length you require. being male to male of course
this would inve some soldering however and i am not that good at it... just make sure the connectors are lined up and maybe that will work. saves buying a tool that will cost a small fortune anyway.