The POWER STATION and
POWER STATION 2 are our most popular items, and we have sold tens of thousands
of them. We offer our famous 3 month (talk nice and it's 6 months) warranty
on this and most of our products!
BATTERY FACTS OR HOW MUCH LIFE
CAN BE EXPECTED FROM A BATTERY for an HF RIG?
If life was ideal, a 20 Amp-Hr
battery would put out 20 Amps for 1 Hour, or 1 Amp for 20 hours before
it was exhausted.
Rule #1 Life is not ideal, so it won't put out 20 Amps for 1 hour, but read on for the good news.
Rule #2 All gel-cell batteries, are measured over a 20 hour period (therefore, for a 20 Amp-Hr battery, 1 Amp for 20 hours is correct). This is called the C20 rate, and the reason that you get a full 1 Amp for 20 hours from a 20 Amp-Hr battery.
Rule #3 If a battery is discharged faster than the C20 rate, the capacity of the battery will be diminished. If you draw as many Amps as battery’s Amp-Hr rating (i.e. 20 Amps from a 20 Amp-Hr or 7 Amps from a 7 Amp-Hr), it will last only about 60% of an hour or 36 minutes at which point the battery will appear to be discharged. (Ignore the rest of this rule unless you’re a technoid). The interface at the Acid/Plates (where the reaction occurs) has been exhausted of the electrons faster than they could be replenished with those located within the plate. You’ll then walk away from the battery thinking it’s dead, and return sometime later only to find out that some useful charge has "returned" to the battery. The reason is that those unused electrons have had time to migrate from the center of the plates to where the edge of the plates at the lead/acid interface where the reaction occurs, so the battery has "come back to life".
Rule #4 DON’T LEAVE A BATTERY COMPLETELY DISCHARGED FOR ANY LENGTH OF TIME OR IT WILL BE DAMAGED. This is true for any type of battery. A battery left in a state of discharge will be ruined. When in doubt, top it off! Think of a car battery! When you accidently leave on the headlights, you should immediately re-charge it, not charge it the next time wish to start your car!
Rule #5 Don't discharge a 12 Volt battery below 10.5 volts for any significant amount of time (Same rule as #4 but we're trying to make a point. Some people think that if it is a 12 Volt battery, the battery is still at half charge at 6 Volts. This is totally incorrect. Do not discharge the battery to this state or it will be permanently damaged! The battery is COMPLETELY discharged at 10.5 Volts. It is even better to discharge it to 11 Volts and recharge more often, as this increases the life of the battery dramaticlly! The POWER STATION has a meter to aid you in preventing this. Should this occur, immediatly recharge the battery and you may be able to save the battery. Even deep cycle batteries have a MUCH longer life when they are not deeply dishcarged, but instead moderatley discharged and then recharged
Rule #6 Don’t overcharge
a battery by leaving it hooked up to a wall charger for weeks at
a time unless it has a regulator. Our POWER STATION has such a regulator
and can be left charging indefinitely, but to save weight and size, our
smaller POCKET STATIONS and POCKET GENERATOR do not have an internal regulator
for the wall charger. These units should be charged for 24 hours and then
unplugged
Example: For simplicity define an HF operating session as 1 Hour. During an hour you talk for one minute and listen for two minutes (i.e. you talk for 1/3 of the time for a total of 1/3 Hr and listen for 2/3 Hr). Even though your HF rig states 20 Amps during transmit this, occurs only during voice peaks on SSB. Since the peaks are at 20 Amps and the valleys of your speech are much lower, the average is only about 6 amps for transmit when you look at the area under the current vs. time curve. To compute how long a battery will last for your HF radio, define the current average during TX as 6 Amps, and during RX as 1.5 (or 3/2) Amps. (Note AM & FM use a steady current, review your radio's spec's for the current draw).
Current (During Tx) x Time +
Current (During Rx) x Time = Amp-Hrs Required (Total)
Amp-Hrs for TX + Amp-Hrs for RX
= Total Amp-Hrs used for 1 Hr of operation
(Current Avg. for Tx) x Time +
(Current for Rx) x Time = Total Amp-Hr
6 Amps (Tx Avg.) x 1/3 Hr + 3/2
Amps (Rx) x 2/3 Hr = Total Amp-Hr
6 x 1/3 + 3/2 x 2/3 = Total Amp-Hr
2 Amp-Hr + 1 Amp-Hr = 3 Amp-Hr
3 Amp-Hr = Total Amp-Hr Required
for 1 session.
THE POWER STATION is a 7 Amp-Hr battery, so you should get more than a couple of sessions (i.e. a couple hours) with a POWER STATION or POCKET STATION 7. THE MEGA STATION has 17 Amp-Hrs, and so would last about 5 or 6 sessions. Again, these are approximations. Each radio as well as the operator have different Tx & Rx characteristics. Some of us are more long winded than others, and hence the number of sessions would be reduced or increased, but this is a very good analytical approach.