Radio battery voltage

I was thinking about making an external battery pack for my camp radio.

I think my battery right now at full charge is around 8.4V and will drop from there.

What batteries in series should I run?


Or can I have a bank of AA batteries in series to 9V?

I think I will need a 9 or 10V solar panel I have a few here now with a 7V output but i dont think that will be enough to charge with.

Any and all thoughts welcome.

I guess the first question is, what is the radio that you want to power?
2nd. How much do you want to spend?
What resources do you have for charging?


Theres 2 baofeng radios that i want to power, one is a uv21 and the other is a uv5r.

Going to buy a solar panel for charging.

Trying for a reasonably cheap build but open to all suggestions.

What I’m trying to find out is what is the normal voltage that the radios operates at. Highest input voltage for the board to power on with.

I think im going to use 2 18650’s in series for 7.4V.

It looks like thats what the TIDRADIO H-3 is using.

All of the handhelds I own (none are Boafeng) are spec’d at 7.4V. The on-board voltage meter shows around 8.2-8.4 volts fully charged and around 7.2 volts at 15% (lowest I have gone). I do not know what the amps draw is but that will change depending on what frequency and and power setting you are using.

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Thanks that what i thought but wasnt sure.

Now im going to tear apart the battery pack on the wifes old computer. See if i san save anything there.

Well 4 of the 6 18650 Li-io batteries were still good. Charging them now to make sure that they still are good. Not sure the capacity, markings are faint. But it was a Sony Viao battery pack.
Charge controller for a 2S is under 5 bucks.

Got the 4 of them charged and balanced them to put them together. I’ll need to get 8 more of them for the 2nd. Then both will have 6.

36 hours plus into testing the battery and it is still showing about 50% and 7.1V. Going to try and make a solar charge controller next with some old 7V solar panels from the dollar store…

Nobody’s going to want to steal this…lol

This might have been a little neater way to go.
My Baofeng will run a week on one of these batteries and the USB can be charged from a solar panel.

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What is the terminal voltage of that charger when charging. My guess is the load drops it down below what the new batteries need to charge. Check the current too.

This radio is going to be placed in a shelter. Im just using some scrap material to make it with.

I have to make it so that nobody will want to take it.

Cant make it look like they can sell it.

The current is low from the base charger. Under 1 amp. Voltage is around the 8.4V mark.

I was able to hook up a meter to the charger and the batteries took about 3400 mAh of juice.

Any thoughts on a possible ground plane for this type of antenna placed in a tree.

Should i screw a small plate to a branch and epoxy the antenna to it, or go without one?

Well i might not be able to use this radio for what i was wanting to. I picked up some hand mics and the mic works fine in the orange radio, but not the one with the messed up GPS.

Probably going to have to buy a new 20 dollar radio.