Tech Notes
Use a Computer UPS at your Remote
Have you ever done a remote broadcast where you were really worried about power? Maybe you were stuck running a long extension
cord, or there were power dips, or the lights kept flickering, or circuit breakers occasionally tripped. Been there, done that?
If you had a computer running under those conditions, you might have at least thought about bringing an uninterruptible power
supply (UPS) along. Somehow, we never give the same thought to the fancy circuitry in audio codecs, mixers, and so on. A number of our
customers, however, have started bringing a UPS to their remotes, and have been very pleased with the results. The most critical items
to protect would be the audio codec (and TA, if external) and the mixing board, if one is used.
A UPS can do several things for you at a remote:
- It will offer protection from power dips, "brown-outs," or intermittent dropouts. What seems like a short dip may be long
enough to drop your telephone connection, forcing you to redial.
- The UPS will give you some insurance against a long power failure. Most UPSs are rated for the fairly high wattage loads of computers
and monitors, giving 20 minutes or so of running time. What they don’t tell you, however, is that the UPS will run a long time on
a light load like an audio codec. We did a test at Comrex where we ran a HotLine (POTS codec) on a 280 watt UPS. We got 5 hours of running
time! Even with a mixer plugged in, you could expect hours, rather than minutes of power.
- The UPS has spike protection. Considering some of the funny things that must run around on power lines in large arenas, for example,
this may be good insurance. A spike may not permanently damage your equipment, but may send it into "never-never land" until
you power it down and restart.
When choosing a UPS, here are some things to consider:
- Wattage won’t be a big issue unless you feel you need to connect power amps, etc. For the light loads mentioned above, a 200-300
watt model should be more than adequate for long outages.
- Make sure any audible alarms can be defeated. Some UPSs have DIP switches on the back to set such features. Obviously, you don’t
want your mikes to pick up a "beep" every time there’s a little voltage sag. On the other hand, you may want to keep the "2
minute warning" alarm that alerts you when your battery is about to die.
If you start using a UPS, make sure that it is charged before your broadcast. Also, follow the manufacturer’s instructions for exercising
it from time to time to keep the battery healthy.