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Tuesday, April 04, 2017

TYT MD-380 Charger Modification

Here we have two different modifications to the popular (and highly hackable) Tytera MD-380 DMR/Analog 70CM radio
  • Modification of charger to disable "green" led when charger is powered. After modification, charger will only light up "red" during" charging and will be off when charging is complete.
  • Addition of a capacitor and RFI bead to cut down radio frequency interference RFI radiated from the charger base when used with a switch mode AC to DC adapter

Here is the charger indicator modification
Here is the RFI suppression modification before and after
The large electrolytic capacitor and inductor were loose on the PCB, I re-soldered them so they sat flush to the PCB which also helped RFI suppression
The charger is supposed to take an input voltage of 12.5V and an output of 8.4V. Measure your AC to DC adapter with a multi meter on both sides. Any output to the charger pins between 7.9 to 8.4V is safe. Any lower or higher will damage your battery and the the total number of charge cycles it can take in its lifetime. If your Ac to DC adapter outputs more than 12.5V, you may want to replace it with a more appropriate one or add a dropping resistor to lower its voltage.
Steve K2GOG

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