all those bases had the same circuit, sc6038 based linear charger.
slow as fuck with a 10v maximum input.
what you cant see is that i sliced 2 of the boards up to retain the input connector and mounts.
it works well - upto 2Ah charge(i set it to 1Ah) and it smart-charges a 2cell lithium pack.
old circuit charged an 1800mA pack in about 6hours!!
it's a compromise,
they used a linear charger so you could keep the radio on in the base,
but because it's linear they had to keep the current low and the voltdrop to a minimum(10v) to keep it from getting hot!
i did not try to run the radio on the base now, but i bet there is lots of rf noise from that inductor!
Based on what mine was before it croaked, it was set at a charging current limit of 400mA, so 1.8Ah in 6h is about right taking in account absorption phase and charging inefficiencies.
At 400mA the chip would have to dissipate 1W+ which is excessive for a SOP8 IMHO.
Well I ordered one, hopefully it works. And no CA LEDs, I think the old one in the charger is a CC? I suppose I could just use two discrete LEDs hidden behind the hole or build a light pipe for the LED on the board... or add two PNP transistors and two resistors...hmm...
Probably will also have to mod the board to 1A or less max charge rate to the 1.8Ah battery..
to set the board for a 2cell pack you blob-link a pair of pads,
to switch from 2Ah charge to 1Ah you remove one of a pair of 0.1ohm shunt resistors that are in parallel
Eh, the LED is not a big deal. Definitely not worth it to get a hundred of the CA LEDs but I may end up putting in a CC unit with two 2n3906's and resistors... mainly because I have a large pile of 2n3906's I'll never finish using up...
BTW, your UV82 original charger board looks better than mine...though not any better than the UV6R.
double ptt comes into play when your talking with 2 groups you want isolated from each other.
great on work sites.
uv6r functions like a uv5r - just built better.
dual watch with single ptt is a pain in the ass, you have to constantly be checking the A/B flag before transmitting, or put both on the same channel.
Work sites? using ham radio? Or using Baofeng instead of a legal part 90/95 radio (for USA...)? :o
Yeah this radio is not quite FCC approved for what dual PTT would be nice for. Using the dual watch for two amateur repeaters and you don't necessarily know who's talking on which repeater even if you recognize the voice but don't know which repeater...
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