(04-30-2014, 03:31 PM)JohnNJ Wrote: I'll list the steps. See if you can follow it to it's incompetent conclusion.
I have no idea how this all worked out for you, but I can tell you what I did, and what it cost:
* Deep-Cycle 100+ amp hour battery from Tractor Supply Company: $95
* 750 Watt Inverter from Harbor Freight: $50
This runs my machine, with the humidifier on high, for a whole weekend.
The reason I use the inverter (12V -> 120V) is because it feeds the machine's power supply maintain an even voltage, where just a battery goes down as it's used.
Also, if you hook it up backwards, you can only fry the $50 inverter, not the CPAP.
It's not exactly portable, but if you're doing "car camping" or can arrange to borrow a battery, it works nicely.