Battery and Power
The battery, power level and power switch values depend on the radio. The Radio reference has them for each radio. A radio without a battery (a mobile on a fixed supply) has none of the battery items in this chapter: no battery icon or percentage, no Tools > Battery page, no Battery saver or Low battery warning setting, and no battery warnings.
Battery level
The status line shows the battery as an icon and a percentage. The percentage turns to the warning color at the low battery warning level and below. The level is set in Settings > Power > Low battery warning (15 % by default).
OK, 6, 9 opens Tools > Battery, which shows the level. At the warning level and below it also shows "charge soon".
The radio reads the battery once a second. It doesn't read it while transmitting or for 3 s after, because the voltage sags under transmit.
Low and critical battery
At the low battery warning level the radio shows the banner "Battery 15%: charge soon" (with the actual percentage) and plays the low battery beep. The warning repeats every 5 minutes while the battery stays at or below that level. It stops once the battery is 3 % above the level (charged).
Most radios also have two voltage thresholds. Whichever warning comes first applies.
| Level | What the radio does |
|---|---|
| Low | Low battery beep (800 Hz, then 600 Hz), again every 2 minutes. The backlight is limited to 30 % |
| Critical | Critical beep (600 Hz three times), again every 30 s. Every transmission is refused |
Three readings in a row below a threshold change the level. The level goes back up when the battery is 0.2 V above the threshold. A radio without voltage thresholds has the percentage warning only.
Transmit power
Each radio has its own set of power levels. Each channel's power comes from the codeplug. A channel without one uses the radio's default level.
| Way to change it | Levels |
|---|---|
| *, 1 | Three steps: the radio's lowest level, its default, its highest |
| Power level key on Home | All of the radio's levels, one per press (radios with that key only) |
Both changes are temporary. Hold OK to save the level to the channel.
Power levels use the radio's factory calibration. Use the lowest power that reaches the other station.
Backlight
Settings > Display > Brightness sets the backlight level. Quick settings has it too (*, 9).
Settings > Display > Backlight time sets when the backlight dims to a fifth of the brightness. It goes off after four times as long. Any key brings it back.
Battery saver
Settings > Power > Battery saver puts the receiver to sleep on an idle FM channel. After 10 s without activity the receiver sleeps and wakes for 100 ms at a time to listen. Any signal in a listening window wakes it fully. It is off by default.
These stop the battery saver:
- a key press, monitor, scan or VOX;
- a DMR channel, or hotspot mode;
- a channel the codeplug marks "no battery saving".
Auto power off
Settings > Power > Auto power off switches the radio off after a time without use: Off, 30 min, 1 h or 2 h (Off by default). A key press, a call received or sent, a scan and hotspot mode count as use. One minute before, the radio beeps and shows "Switching off in 1 min / Any key keeps it on". Any key cancels it.
On a radio with the power switch on its volume knob, the knob is still on when auto power off acts. Whether each radio can cut its own power then is in the Radio reference. A radio that can't cut it comes back up after 2 s, shows "Couldn't switch off / Turn the knob off", and keeps running as before.
Turning off
Turn the radio off with its power switch. On the handhelds this is the volume knob, turned counterclockwise until it clicks. Where the radio sees the switch, it finishes what it is doing (an ARS deregistration, at most 3 s), saves its settings and switches off. The Radio reference describes the power switch of each radio.