Battery saver, what does it do?

The battery saver function has been around in Motorola two-way radios for a very long time. As the name suggests, it helps to reduce the current consumption of the radio during receive thereby improving discharge time (i.e. battery takes longer to get flat).

In order to reduce current consumption during receive, the microprocessor will turn the receiver backend on and off when there is no traffic on the channel. The net result is that the current drain from this circuit is reduced by anywhere between 50 and 90% depending on how busy the channel is.

The downside of this feature is, since the receiver gets turned off every few milliseconds, there is a chance that the radio will miss the first part of a call. To overcome this, the receiver can also be woken up by listening for the preamble bits that normally get appended to the start of a transmission. This is enabled in MOTOTRBO radios by ticking Preamble.

If you want to disable battery save altogether, you can do so by un-ticking Receive. This will switch off the receive battery save feature I've described above but will increase current drain. This maybe useful in Control Station radios which are connected to an external power source (i.e. battery drain is not a problem).


  1. Many clients that still use the old GP3XX series analog portables and bought DP4XXX series as replacements for their radio fleet, complained that the DP4XXXs in analog mode aren't able to communicate with the old radios. After investigating I have found that the DP4XXX don't "wake up" when in battery save mode from analog transmissions hence you need to un-check the "receive" in battery saver. Seems very weird but this workaround solves the issue. One thing to mention is that those clients don't use any signalling scheme (5-tone/MDC etc) where the tones at the transmission start would force the processor to wake up just before the voice begins acting like a preamble. Further more this isn't a firmware bug. (The same behavior occurs in multiple firmware versions). Also this happens even more when the DP4XXX is at the lowest edge of receive level (-115dBm to -121dBm). Just received a DP1XXX with the same behavior.

    1. I've not seen that before. Have you reported it to your dealer/distributor/Motorola? If yes, what did they say? If it was reported to Motorola, did you get a case reference number? See


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