mobile power source

[joshuadenny]

i want to start having my own field days, of course maybe once winter calms down. but, i cant very well run my car battery down and then be stuck 45 minutes later. i would like to be able to run bct15, 996, a new shortwave that i havent decided on yet. basically enough power to supply a 6 slot power strip. any thoughts??

 

[VernM]

You won't need a lot of battery if that's all you plan on running remotely. Figure the drain (amps per hour) and you likely will be able to get by on a small deep cycle battery. I have a larger one, a Group 29 marine/golf cart deep cycle, in a converted Coleman cooler sitting under the operating table for UPS/ power outages and remote use. In the cooler along with the battery is a trickle charger with de-scale capability (BatteryMinder.com) and a small (120 watt) inverter, should I want to power something off 120 volts for a time. The cooler is vented with little round house vents available from Home Depot/hardware stores, and has a 12 volt socket on a bracket for auxilliary 12 volt uses. Fuse block/terminal block is screwed to the inside of the lid. Total cost under $100 with battery. Been in use more than 4 years with no ore maintenance than checking the battery fluid once a month or so. If you have the space, that's a good solution that will lend itself to other uses too.

 

[ResQguy]

Just what kind of battery is in your car? If 3 radios in receive mode will run down your battery in 45 minutes, you have some auto repair to do first!

But really, how about a portable jumpstarter and a 3 way 12v plug adapter to power all three, and you can carry it with you to a picnic table or whatever.

 

[specman]

A lot depends on how you have your equipment set up; if your radios are not actually installed in your car I second the vote for a separate deep-cycle battery in a mobile container that can be used for your field work.. a decent sized battery should last the better part of a day for your purposes and can be charged up afterwards.

If your equipment is physically installed in your vehicle and you want it to run off the vehicle power than you have more planning to do. In my case I have a fair amount of equipment installed in my vehicle and wanted to be able to run some of it for a fair amount of time while not running the engine and not worry about running down my starting battery. I opted to install a second battery (a deep-cycle type) and use an isolator to keep it separate from the main battery and yet have it charged from the alternator when the engine is running. This setup works extremely well for me. The isolator I use also has the feature to allow the second battery to "assist" the main battery for starting if needed. I also elected to replace the stock alternator with a high-output model to handle the extra load when needed.

If you elect to go the second battery route be advised there's a lot of different ways to go about it depending on your needs. Also be aware that there's quite a bit of bad advice and improper installations out there; make sure the information you use comes from qualified sources. In case NEVER place a lead-acid battery in the passenger compartment, and ensure it's vented/restrained properly if installed elsewhere.