I like my Baofeng Ham radios. But, one thing that annoys me is the battery charger. The radio's battery charger uses a charging base and a separate transformer. To turn off the charger you have to unplug the transformer from the mains power socket, which is not practical at all. If you leave the transformer plugged to the mains it will be wasting some electricity and generating RFI, as all switching power supplies do, not matter how good they are.
|Baofeng UV-5R, UV-B5 battery chargers.|
So, I modded my Baofeng UV-B5 battery charger into a single unit device with automatic On/Off power switch. After this mod or hack, the Baofeng battery charger turns itself On automatically when the radio is put in the battery charger and turns itself Off when the radio is removed from the charging base. No more wasted energy, no more RFI, no more flashing leds!
|Modified Baofeng battery charging base with AC power source.|
The mod is really simple. All that is needed is an small AC switch, power cord and a soldering iron. You can find links to buy the parts at the end of this post.
|Automatic On/Off charging circuit.|
After the teardown of the Baofeng UV-B5 battery charger base unit, the transformer PCB can be placed inside the unit with minimum hassle. The DC input jack is de-soldered and the DC output from the transformer PCB is connected to the input of the smaller base unit PCB. One wire of the AC cord is soldered to the transformer PCB AC input and the other to one pin of the micro-switch. Another wire connects the micro-switch to the transformer PCB. The transformer has a 3mm LED that you may need to bend in order to fit both PCB's inside the base case. To prevent any accidental short circuit insulate any wire solder joint and use some insulation material between both PCB's.
|Add isolation to prevent any short circuit!|
The switch can be placed in place of the center charging contact spring, since is is not connected to the charging circuit. Some glue will hold the switch in place.
|Battery charging base. Note the micro switch in the center of the contacts.|
And that's all. Now you have an single unit radio battery charger with auto power On/Off!
This project was done for the Baofeng UV-B5, but it can be done for other radios, like the Baofeng UV-5R and other brands and models as long you find a way to place the transformer PCB inside the base unit.
Please take a look at the following video describing the project and give it a thumbs up if you like it!
You can buy the micro switches here.
You can buy a power cord that matches your country's plug type here.
Interested in the Baofeng UV-B5?
Buy the Baofeng UV-B5 cheap from Banggood!
Buy a Baofeng UV-B5 battery charger from Banggood!
Buy a Baofeng UV-B5 replacement or spare battery from Banggood!