Battery Monitor for QRP operations

Posted by Fred C (W6BSD) on Jul 14 2019

I often use small 7 or 9 Ah lead acid batteries because they are convenient and inexpensive. For example, my AllStar node at home is plugged to a battery like the one on the following picture With this battery I can continue to transmit for a few hours even when there is a power outage.

The following PCB turns a common sealed lead acid battery (SLA) into a convenient power source for radio equipment or other electronic projects. Just slide the PCB into the batteries connectors and you can use a low power radio. You also have a USB connector convenient for charging your phone or logging device. This "Battery Monitor" uses a digital voltmeter allowing you to easily check your reminding capacity. There is a convenient 2.1mm barrel power jack for charging.


Battery Monitor schematic
Battery Monitor schematic


Battery Monitor PCB top side
Top side
Battery Monitor PCB bottom side
Bottom side

Final result

This is now the battery monitor looks like once assembled and installed on a battery and ready to use.

Battery Monitor PCB bottom side

You can download the Battery Monitor Gerber file and order your PCB from any PCB manufacturer.

I also have a dozen PCB left, and if you are interested I can send you one. Just send me an email. You can find my email address on my QRZ page.

 QRP      Battery