The Star Power 17 has all of these features:

• a large 17 amp-hour capacity rechargeable battery (with somewhat less capacity when used in temperatures below 32 degrees F), which is enough power for several nights of observing with most telescope and accessory combinations

• two 12 VDC cigarette lighter plug outputs for powering scopes and dew heaters, with sliding covers to keep them dirt- and debris-free when not in use

• separate recessed 3V, 6V, and 9V DC 5.5mm male pin jack outputs for powering accessories or recharging a cell phone at a star party (tip positive, ring negative, 1 amp maximum load), using the cord below

• a cord with a female 5.5mm pin jack plug on one end to connect to any of the three DC outputs mentioned above for powering a variety of accessories; the other end of the cord terminates in a four-way tip that has 1.- a 5mm female pin jack plug, 2.- a 5.5mm female pin jack plug, 3.- a 3.5mm male pin jack (tip positive, ring negative), and 4.- a 2.5mm male pin jack (tip positive, ring negative)

• a separate 8’ long DC power cord with a cigarette lighter plug on one end for connecting to one of the cigarette lighter plug outputs on the Star Power 17 and a female 5.5mm pin jack plug for connecting to the 12V DC input on a Sky-Watcher EQ5 PRO mount telescope on the other end

• a very, very bright 800,000 candle power built-in spotlight for scope setup/breakdown and for finding your way across a dark field (definitely not for use at star parties if you want to preserve your dark-adapted vision . . . and that of other observers)

• a bright built-in red lens lamp for scope setup and takedown (too bright for reading star charts; a variable brightness LED flashlight is still best for that); the lamp can be removed from the Star Power 17, although still connected by a power cord, and attached to any convenient metal surface by means of a magnet on its back

• separate on/off switches for scope power, red lens lamp, and spotlight

• battery indicator lights that show the status of the battery – ON/ready to use; needs charging; charging; or OFF/fully charged

• an AM-FM radio with built-in speaker to keep you company when observing alone (it’s best to use a separate CD player or iPod and headphones while at a star party, in case your choice of music doesn’t agree with the other observers nearby)

• an external 110V/220V AC recharger for replenishing the Star Power 17’s battery charge up to 100 times or more; the AC adapter can be used with any 100 to 240 volt 50/60 Hz AC power supply

• built-in heavy jumper cables for starting your car in an emergency (250 amp cranking capacity for 5 seconds when fully charged), and

• a molded-in carrying handle.

To calculate how long the 17 amp-hour capacity Star Power 17 will operate your particular complement of equipment, add up the maximum amperage ratings of your telescope and your telescope accessories. Divide 17 by the total amperage draw of all your components to find the worse case number of hours that this Star Power 17 will operate your system. Keep in mind that accessories will usually not operate continuously at their full rated amperage. A dew heater might be rated at a 1-amp draw, but that is when it is turned up to maximum power. Seldom are dew heaters turned on full and left at that setting. Operating at only 1/4 to 1/3 of the rated power is usually more typical. The actual operating time of the Star Power 17 on a single charge can therefore often be two to three times the length of the worst-case scenario calculated above. Your operating time will depend on the ambient temperature and the particular combination of components you are using.