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WD8QCN

Joined: Sat, Apr 4th 1998, 00:00 Roles: N/A Moderates: N/A

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Baofeng UV5R Charger Fix May 26th, 14:52 1 895 on 26/5/21

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Baofeng UV5R Charger Fix WD8QCN on 26/5/21
I recently obtained a Baofeng UV5R from a friend who bought it as his first radio. He gave it to me because he became frustrated with battery charging issues, the latest being that the battery would not take a charge for more than a few minutes at a time.

I was able to "shock" the battery back to life by applying a slightly higher than normal charging voltage (12V at the load-side contacts) while monitoring the battery voltage. Once above 7.1V, the regular charger was able to do the job, and I quickly noticed that one spot on the bottom of the charger case got extremely hot within 10 minutes. I was able to pop open the case, and saw that the source of the heat was a tiny, surface-mounted charge-control IC chip.

Excessive heat kills electronics, so I decided to fix the problem. I put Kapton tape over all of the exposed leads and connections on the circuit board, leaving only the top of the IC case exposed. I then placed a 1.5 x 3 inch piece of foil tape over the chip to act as a heat sink - making sure that it was firmly in contact with the IC case. This has done a great job of spreading out the heat, and I no longer worry about the case melting or the charge controller burning out.

I hope this helps some others who have this radio!

73, WD8QCN

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