Servicing data for "Pony Travel Charger" GW/TCH/POWY
This was interesting for me, but I think it'l only interest other people servicing or modifying this type of cell phone charger...
The charger is a switch mode supply that will run off 100-240V AC. This isn't rocket science these days, but the interesting thing about this wee device is it also has an adjustable output, from 3 - 12 volts DC (regulated).
The output voltage is set by an external resistor.
This resistor is built into the charging cord, and thus different devices can use the charger, each with their own resistor built into the cord, so they all get their correct voltage :)
Yeah that is rather cool.
The best part is that the user doesn't need to know any of this, they just plug it in and it automagically charges their phone....
This was working well for my friend Celine, until mechanical fatigue at the charger end of the cord stopped it from doing anything... :(
So I try to get info from the web to fix it and .... NOTHING !
Hence adding it onto my site.... info to the people who need it :)
This shows the details of the charger.
This is the phone that it was charging.
The cell ph battery.
In the center of this photo you can see the output voltage setting resistor. See how the leg is broken off at the body of the resistor.
Note also that it is a 2.95K ohm, 5 band, precision tolerance resistor, as I didn't have any of these "in stock" in my humble garage, I compromised....
As you can see I needed to use two resistors in series to get the desired result.
I used a combination of a 2.2k ohm 5% added in series with an 820ohm 5% to make a ~3k ohm resistor with a tollerence of 5%.
It gave an output voltage of 5.85 volts, which is exactly the output of standard chargers for these phones. So both Celine and her phone were very happy :)
The finished result prior to heat-shrinking.
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