St. Louis County ARES®: Field Station Basics

Recommended Field Station Basics

Transceiver:
We recommend a mobile 2 meter transceiver that can output 25 watts or more. A dual-band transceiver (2m/70cm) is preferred. We strongly recommend installing Anderson Powerpoles on the power cables, as this will allow you to connect to many other power supplies should your own fail. More information about Anderson Powerpoles can be found on the Resources main page.
Antenna system:
It's up to you. Some operators prefer J-poles. Others like ground plane antennas better. High gain is great, but the main things you should be concerned about are how portable is it and how easily can you get it up. Use an omni-directional antenna rather than a directional one, though it may be handy to have both. Don't forget that you'll need a mast of some sort, and a base for the mast (these will be covered in separate articles). If you use coaxial cable (and you probably will), use high quality coax rather than inexpensive packages you may find at a hardware store. Coax is very lossy, and a long run of cheap coax may lose over 90% of your signal. Expect to need at least 25 feet of coax. If you want to keep your coax short, consider carrying more than one segment and have adaptors so that you can join them is you need something longer.
Power:
This is likely to be the most difficult element of your field station. Do not assume that there will be "emergency power" available at the site where you'll be deployed. You should plan on taking your own power source. The simplest thing that you can do is to take some batteries with you. You cannot count on being close enough to your vehicle to use it as a power source, and solar, wind, and water systems cannot supply you with bursts of power adequate enough to transmit. This is where an understanding of Ohm's Law comes in handy, as you will need to calculate how long your batteries will last at the power level you will be using to transmit. Some operators do fine with 7.5 ampere hour batteries, but they have to be very conservative with their transmission power levels. Others haul in more powerful batteries, but they are also considerably heavier. It's a trade-off between power and portability and you will have to determine what works best for you. Our only recommendation is that you use "communications" batteries, also know as UPS (Uninterruptable Power Supply) batteries. These are generally SLA (Sealed Lead-Acid) batteries. Do not use automotive batteries as they are not meant to be discharged to low levels.
Accessories:
We could fill pages and pages with accessory suggestions, but the very top item would be a headset (not earbuds). It will almost certainly be noisy wherever you deploy.

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