DC Extension Cable

[Griffin NoName]

Aggie - soldering is beyond me. Zono, getting to suitable shop is beyond me. Blue, thank you for the offer.

I attach below the leads from the URL no one can make work.

If I use one of these, do I have to worrry about + and - or is that only relevant if making a cable from scratch?

[Aggie]

Bugger it for a game of solder, sez I...  that's DavidH you want.

[Bob in a quantum-state-of-faith]

Ah-HA!

Take careful notice of the description:  "centre pin" is mentioned. 

So.  In your picture of the 1:1 plug you currently have, carefully measure the CENTER PIN within the hollow cylinder-- oh, poo-- the difference we are seeing is 0.4mm.  You cannot do that by eye-- at least, I cannot.  A micrometer at the least-- but the pin is recessed, and you cannot get at it.  Bother.

Okay, let's try this a different way. 

Post the model number(s) on your wal-wart (power-brick)-- just post everything on the label.  Also the brand of the device it belongs to, including it's model number.

I'll see if I can find some specs for either the original device's requirements, or the wal-wart itself.  Often, if you can had a replacement power thingy, it will specify the specs for the plug in it's description.  Amazon stuff is good about this sort of thing.

Once you have the plug's specs, or the specs of a replacement wal-wart, we can choose which cord will work.

So. Look at the writing on your thingy, and on the label of your original device-- is it an iPod dock?   

Let's see what we can find out from that angle.

---------------------------

Edit:  is that the actual price I see?  Two bucks apiece?   

You could just buy both, and use whichever one works best...  if the shipping's not killer that is.

[Sibling DavidH]

Hot glue is fine, but I prefer the flexibility of "sensor-safe" RTV or silicone glue.  The blue formula will not corrode your copper wires (the sensor-safe ensures this), and it remains flexible over extended periods of time.

For sleeving, I prefer heat-shrink-- it's a sort of plastic, that when warmed with a hair drier or hot-air-gun, it shrinks to 1/2 or 1/3 of it's original size.  If you slather silicone inside, before shrinking, you get an excellent, protected and waterproof joint.   Smaller heat-shrink tubes over each line, then a larger tube over the whole, re-creating the appearance of a continuous, one-piece wire.   If you take care when soldering the joints, so as to not let them get too large?  The finished diameter is similar to the insulated part, after shrinking the heat-shrink.   The silicone will ooze out either end, I just wipe that off.

Bob, your techniques are clearly neater and more professional; just one snag - these things cost money!  I'm a tight-fisted old beggar and if I can do a job with scrap from my garage junk pile, I will!  (As long as it's safe.)
I agree that your version is preferable to a non-skinflint. 

Griffin - if you use a proper extension you needn't worry about polarity (+/-).

[Bluenose]

Regarding polarity:  So long as the extension cable is wired so that the same wire is connected to both centre pins and the other to the two outer connections, then it does not matter which wire is which. 

[Griffin NoName]

I ordered both as cheap. Hoping one will fit. We'll see.

[pieces o nine]

Excuse me! Did someone ask about reversing the polarity?

[Griffin NoName]

Excuse me! Did someone ask about reversing the polarity?

Have you come in here looking for that well known character DC Jack ? 

[pieces o nine]

Have you come in here looking for that well known character DC Jack ? 

I had to pop in here; I couldn't COAX him to visit me...

[Sibling DavidH]

Sock it to me, baby!   

[pieces o nine]

I'm not sensing any   resistance   to my threadjacking of your sensible conversation...

[Sibling Zono (anon1mat0)]

Resistance is futile... at about 2^oK.

[Sibling DavidH]

I'm not sensing any   resistance   to my threadjacking of your sensible conversation...

Let there be no impedance to the flow of humour.  Oh my goodness, no. 

[Bob in a quantum-state-of-faith]

I'm not sensing any   resistance   to my threadjacking of your sensible conversation...

Let there be no impedance to the flow of humour.  Oh my goodness, no. 

Oh, henry:  I'm all choked up about it.   I no longer have the capacitance for any more laughing.   I suggest we transition to another shell.   This one has lost it's potential.

[Bluenose]

Ohm my, Watt have we here?  Will we have to Volt over a large grid to get anode?  The high tension if killing me!