I have a 12v monitor and a 12v spy camera could I hook them up to a 12v battery pack with a dc splitter, or would there be issues. But I also have a 8v spy camera, is there a easy way to hook it up to a 9v battery?
You need a 12 v pack with enough current to operate them both for some period of time. So you need to know how much current they use in a given hour. They should spec their power usage in watts. So you divide that by 12. That will give you their current draw for one hour. Then, if you want them to operate, say for 8 hours, you need a battery pack with an output of a little more than their total current drain over that time. Say they draw 1 watt each, so that is 16 watts over 8 hours. 16 w/12 v is 1.33 amp/hours. So, in this case, you would want a battery pack capable of at least 1.5 amp/hours. The 8 volt unit is much the same. You need to know it's current drain per hour and then you need a 9 v battery with a high enough amp/hour output to run it for how long it will be on. A simple small 9 v battery won't have enough power to even turn it on, much less, run it for any time at all. You would be better off to use the 12 v supply (if big enough) to run all 3 and just use a current limiting resistor in the 8 v line.
