The PEMS was developed in response to a need demonstrated during the October 2007 firestorms in northern San Diego County. With fires burning on three fronts, two local residents who were trained and prepared to shelter in place relied on a collection of table top and hand-held scanners to keep abreast of the fires progress, evacuation areas, and road closures in order to keep their neighbors informed. Discussions of the monitoring activities that followed in the aftermath of the fires pointed toward a need for a more consolidated and transportable capability for monitoring multiple agencies. Additionally, it was deemed necessary to be able to continuously monitor one or two channels (a command frequency and a tactical frequency, for example) while another radio scanned multiple frequencies of interest. The PEMS has been designed to fill that need. See more PEMS photos. Features
Up to three Uniden DIN-E mount scanners in one portable unit
Powered by 120 VAC, external 12 VDC or internal battery
13 x 18 x 8 (HWD)
25 lbs maximum (all options) Options
Multicoupler for single antenna
External speaker/headphone connector
Panel-mounted GPS/Remote connector Tech Specs
With three scanners operating with the volume control at the 12 o'clock position and what we estimate as about a 20% - 25% duty cycle (at least one scanner receiving a transmission 20% - 25% of the time) the 4.5 amp-hour sealed lead acid battery will last about 4 hours.
Obviously, this will decrease somewhat with the volume controls set louder and/or continuous audio but the standby current for each radio is around 250 milliamps so there is a substantial continuous draw from the radios and there will be additional from the preamp.
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