[carlseibert]

Hi,

If you are making a Line Out Dock connector (LOD) for your iPod, you may run into a discrepancy in how the pins are numbered. (Yes, you can guess how I came to know this). Everybody here and pinouts.ru calls the line out pins numbers 2,3 and 4, which are common ground, right channel and left channel, respectively. ipodlinux, on the other hand, counts from the other end and calls the line out pins 27, 28,and 29. ipodlinux has a photo and a drawing that are very helpful (if you count pins their way, that is). To make matters worse, their photo shows the connector with the "arrow" side down, which is upside-down from the "normal" way of looking at the unit.

If you use pin numbers from here and their photo, what happened to me will happen to you.

So, if your connector is plugged into your iPod, and you are looking at it in the "normal" orientation (click wheel and display facing you), the three line out pins are the second, third, and forth pins from the left. If you turn the connector around and look in the muzzle end of it, the three pins will be one in from the top right. Note that in the "normal" orientation, the contacts in the connector are on "top" (the same side as the face of the iPod, or the side with the arrow marking)

I'll attach a picture that shows the pins we're after.

By the way, on the 3.5mm miniplug, the tip is left, the ring is right, and the shaft is common ground.

I hope this saves somebody some annoyance.

-Carl

.. and oh yeah, the silver wired cable I made sounds quite nice. It wasn't much trouble at all to build, apart from the wrong turn counting pins.

 

[Lil' Knight]

Reading the stuffs on ipodlinux only makes you feel more confused about the side, pins or reversed pins.
The easiest way to navigate the pins is to plug the dock into your iPod and all the pins you need are on the left hand.

 

[sugrhigh]

Very nice post and tip for anyone that wants to make an LOD. Luckily for me, I hook everything to a breadboard before soldering the cables and placing sleeves and things on them; otherwise I would definitely have 2 or 3 unusable LOD's hanging around

 

[fordgtlover]

I posted the following picture a couple of years back, but it seems to have disappeared from the internet. Here it is again.

 

[Chris Connections]

A soldering tip for you,

When soldering your cable to the LOD connector use 32awg cable as it won't snap the pads on the LOD connector.

If you need any tips for making these cables drop me an email.

Chris

 

[carlseibert]

Quote:

Originally Posted by sugrhigh /img/forum/go_quote.gif Very nice post and tip for anyone that wants to make an LOD. Luckily for me, I hook everything to a breadboard before soldering the cables and placing sleeves and things on them; otherwise I would definitely have 2 or 3 unusable LOD's hanging around

Yup! I re-inserted the pins I needed in the first one after my internet-enabled dyslexia episode.

Then, since I couldn't check continuity from the itty bitty recessed pins, I figured what the heck and potted the whole thing. One of the re-inserted pins didn't make good contact, of course. So I couldn't salvage any pieces. I had to go back to Rat Shack for another mini plug. Most annoying. If I was using something fancier than five-cents-a-foot fine silver I would have been REAL annoyed.

On the second try, I lashed it up with clips for strain relief so I could test it with the multimeter and with a signal from the iPod. Then I potted everything. I can't exactly say that means I'm smart 'cause I learned from my mistake, given that the original error was proof to the contrary

-Carl

 

[Chris Connections]

Ok,

Can someone explain to me why remove the pins from the LOD connector, its un-necessary, its tricky and can cause a serious ball ache if done wrong

Chris

 

[ruZZ.il]

interference. Other pins are connected to data pins and the such, which often have high frequency voltage oscillations on them. Since we're all about squeezing the most we can out of things, why not just do it?
How audible is the difference?.. I'm not sure. I haven't done any testing, but I can electromagnetically imagine what could happen. Though I like doing it mostly cause it keeps things neat inside. specially when doing other little mods, like for the ipod touch:

 

[fordgtlover]

I removed the pins to give me more room to work and squeeze the wires in.

 

[Chris Connections]

Interference , hmm i'm going to disagree with you there.

I never remove the spare pins as you never know the day that you might need them

Chris

 

[ruZZ.il]

I've got plenty removed pins in a little ziplock bag. I've had no problem re-inserting them. just pick the right orientation.

Well, I wont argue on the interference anyway. Like I said, I haven't tested it, nor done the maths. have you? I'd still do it for neatness and pin accessibility, but am sure it'd work if one doesn't..

 

[Lil' Knight]

Quote:

Originally Posted by Chris Connections /img/forum/go_quote.gif Interference , hmm i'm going to disagree with you there. I never remove the spare pins as you never know the day that you might need them

Then I'm going to disagree with you

I always remove the unnecessary pins.

 

[qusp]

I remove the pins and put them in a snaplo,ck bag; I never know when I might need them

try soldering 18AWg wires in there without doing it. you can dissagree all you like about the interference it wont make it go away.

I also tend to use a different ground pin to pin 2; usually 15,16 or 29 these are all tied to ground on the motherboard. not only does this give you less chance of shorting one of the audio channels to ground but it also spreads the tension more evenly out across the connector. I think 2 is always mentioned for ground as it is the audio ground pin (common ground is 1) although as I mentioned they are all connected in the ipod. 15 is also easy to bridge to 11 for iphone/2G touch operation

 

[carlseibert]

And why NOT remove the spare pins? In addition to everything else, once the plug is potted solid you can't get back in to make use of any unused pins anyway.

-Carl