Are car batteries ok for portable use

[KC9DUF]

I am a new tech and finally have my equipment. I have my base equipment set up and working fine. My question is regarding a mobile/portable set-up. I have an Ft2800 mobile radio I want to take camping and be able to set up outside along with the antenna (a homebrew j-pole which works great so far). I was considering using a car battery or deep cycle battery as a power source. is that safe? will it work correctly and can I keep it hooked to a battery charger while in use or is that necessary? Thanks for your help
73
KC9DUF

[KG4RUL]

I regularly use small, marine batterie for portable use with either a Kenwood TS2000X or a Yaesu FT100D.  The batteries I am using are about half the size of the usual battery design and have a top carrying handle for eas of transportation.  I have operated either radio for up to 12 hours receive with perhaps a 10%+ transmit duty cycle on a single battery.  I will be operating as a Rover, using this setup for the ARRL VHF QSO Party this weekend.

Dennis

[K5DVW]

Sure, you can do that. I've done that camping many times, but I tend to leave the battery in the jeep under the hood

Actually, if you're going to carry the battery solo, and you dont mind lugging all that weight, it'll work fine. I'd spring for the deep cycle battery since regular car batteries are really not designed to be discharged all the way. That's a fast way to crap out a regular car battery.

If you decide to keep it connected to a charger, be sure to do some on air checks and have someone listen for AC hum on your signal.

[K5LXP]

No, I wouldn't recommend that unless you want to replace the battery often.  Car batteries are designed and constructed for brief, high current discharges, not low, long duration ones.  Using a car battery in this fashion won't "hurt" anything but you'll get far from rated life out of it.  What you're looking for is a "deep cycle", or marine battery mentioned above.  Buy a small charger meant for long-term charging like a Battery Tender and you'll have a setup that will be dependable for years.  A "smart" battery charger such as these can be left connected to the battery indefinitely, so you don't have to worry about overcharging or constantly replenishing the water.  Using a battery as a power source instead of a power supply can be done, but when you compare the cost of the battery and charger, plus the regular replacement of that battery, a standard AC power supply is a much more economical way to go.  Save the battery for portable use.

Mark K5LXP
Albuquerque, NM
k5lxp@arrl.net

[N4TDX]

Over the long term, I think you'll want to use a deep-cycle
marine battery and a charger.  They are made to be recharged after extended periods of use (discharge) and will usually last much longer than car batteries which are made to deliver a lot of amps at once for the purpose of starting a car.  As a rule, don't leave the charger attached while using the battery as a power source.  There are many resources on the web offering primers on battery types and best practices.  Good luck.   Bill, n4tdx.

[N6AJR]

I agree  go with the marine deep cycle batteries, and remember that they produce hydrogen gass when charging or discharging so be sure they are in a well ventalated area, not in your bed room...

Also look into some of the smaller 7.5 and 10 amp hour SLA batteries, found on Ebay for $10 or so. much easier to carry.  they are Sealed Lead Acid batteries that won't spill.  work good if you keep the power down.

also you can pick up a small solar panel to keep it charged for free...

[KB9YUR]

 For little more than the price of a car battery, you can use the all-in-one Nomad 300
 from www.solarsense.com. I've been using this portable unit for over two years powering
 a Vertex VX-150 HT all the way up to an Icom 275H 100watt radio. It's self contained,
 with an 18 amp/hour deep cycle battery, wall wart recharger, 300 watt DC-AC
 inverter and cables for jump starting your car battery should it go dead.
 Highly recommended and I use their 21 watt solar panel to recharge the battery in
 the field.

 George
 KB9YUR

[AA8RF]

If your charger can keep up with your use and you do not get a hum, it is ok to use a car battery (it acts like a GIANT capacitor on the battery charger output).

If you discharge the battery very low (because the charger cannot keep up) it will shorten its life. If you want to use it this way get a deep cycle battery.

I run a portable jump start battery in the shack as the power supply for my main HF rig with a trickle charger on it. Works great and I have a charged up emergency power source as well.

-Jim