How do I make a 6 volt Li power supply for radio?

[ken2400]

I have a radio that takes 4 C cells. I was thinking of buying some C NiMh then I thought what about Li? Cells are 3.7 V so how would I get 6 volt without to much loss?

Thanks

 

[Mr Happy]

I have a radio that takes 4 C cells. I was thinking of buying some C NiMh then I thought what about Li? Cells are 3.7 V so how would I get 6 volt without to much loss?

There are two things that will act to your advantage:
1) 4 C cells does not exactly equal 6 volts
2) the probability that the radio requires exactly 6 volts is very low

Therefore, if you put two Li-ion cells in series you will have a power supply that is about 8.4 V at full charge, and about 5.6 V when discharged. In all probability the radio will accept this range of input just fine.

The reason is that typical analog transistor circuits are not fussy about their power supplies. One thing that might be an issue is the voltage rating on any capacitors, but this is a low risk when the supply voltage is less than 9 V. Small capacitors are typically rated at 25 V or more.

 

[Tekno_Cowboy]

You may want to contact the manufacturer on the acceptable input voltage range. Could prevent a fried radio or open up other options.
You could always just drop in 4 NiMH C-cells and call it good.

 

[VidPro]

probably a perfect candidate for ni-mhy , because of the TIME factor, in many years you are more likly to have the li-ion be dead, than the ni-mhy.
and they have Low self discharge ones now too.

 

[ken2400]

You make a good point. Li seems to have a shorter life span.