Proprietary ResMed A10 Power Connector Electrical Details

[yrnkrn]

I'm sorry but the board does not let me post the image or link although I have 4 posts. 
Remove the space from the link:

http://www.imgur.com/6c20DzX.jpg

Yellow resMed on the left, AliExpress on the right

[Snoopy.pa30]

Thanks @yrnkrn.

I really appreciate the picture.

More motivated to pound the pavement to find one at local repair shop.

 

Snoopy

[Snoopy.pa30]

UPDATE

I found an old HP power supply brick with the 7.4 mm x 5.0 mm connector with center pin. 

I "carefully" disassembled the brick (as I plan to put the components back in to it for better asthetics).  I made up the simple circuit (diode and resistor) and connected the batteries and machine.  It ran fine last night.  

Now I have to move from the breadboard to a mobile (Scout Camping) format.
I plan on using the block connectors (so I have a seal on the brick). 
I mistakenly cut off the brick "Mickey Mouse" plug end.  I should only have removed the wall plug.  Just means that I will have the fuse spliced in external to the brick, and it will be more obvious that this is not a normal wire.  Not that the battery connector ends couldn't be the signal...

Since I will be using the plug I will make the bridge with the diodes to ensure proper polarity.  The 47k ohm resistor for the signal pin and then epoxy the brick back together.

Great little Scout project.

THANKS to all who contributed on this thread, and those who on the other threads that made the circuits and did the testing.

 

Snoopy

[yrnkrn]

That's good to hear!

Do you use 24V batteries directly or 12V with DC-DC converter?

[Snoopy.pa30]

For Batteries, I am using 2 of 12V 12Ah batteries connected in Series to give 24V.

They are from a couple of less used UPSes. 

Since I am away camping with the kids, not a problem to just pull the batteries for the weekend.

I will probably get the 12V-24V up converter (when I have time to let it arrive through snail mail) and see how long one battery will last. 

Until then, slug the dual battery setup.  Or better yet, get the Cubs and Scouts to carry it..

Snoopy