28 July 2014

Painful discovery about Baofeng UV-82L

Few months ago I bought a Baofeng UV-82L so that I would have a 5W dual-band handheld, since the little UV-3R has been stuck in the car on a fixed frequency.

Seconds after paying it I realised Baofeng UV-82L does not have a DC socket for recharging or powering the unit: it works off the battery and it requires the charging base. Not so practical if you are often on the move, or you don't want to keep the base on the desk all the time.

That said, the transceiver works as expected. Being confined to "memory mode" (without power-cycling it) is not a big deal once local repeaters have been programmed. But yesterday I did a painful discovery. I was checking if a friend was still up on a mountain and I moved around the flat with the UV-82L in my pocket while doing other things. Then I heard a /P station calling on the VHF direct frequency for mountain op's and engaged a QSO with him. During a transmission I felt a mix of burning/biting in my hand holding the radio ... right there where battery contacts are located!

My palm, slightly salty-wet from Summer sweat, was draining current out of the Lithium battery pack. I haven't had time to double-check with a resistor and ammeter, but most probably there is no reverse-discharge protection diode into the battery pack. There is no fix.

Edit. I confirm, positive charging terminal is connected to the positive battery lead going to the radio. Same goes for ground terminal. At least in my BL-8L battery pack.