Re: TI-H: AC adaptor
[Prev][Next][Index][Thread]
Re: TI-H: AC adaptor
TimRopp@aol.com wrote:
>
> I'm trying to build an AC adaptor for my 85. I have an adaptor that outputs
> 6V DC (which is what the 6 AAA batts output) but it outputs that at (I think)
> 300mA. How do I reduce that to the level that the calc needs? I've tried
> hooking it to my calc by connecting the leads directly to the battery
> terminals. It will turn on and not lose the memory, but the screen is
> totally "lit up". Even at the lowest contrast level, you can't see anything.
> I need to put in something to reduce the amps, but I'm not sure what.
Try connecting the adaptor through a 7805 voltage regulator, which keeps
the voltage at 5 VDC. Maybe your adapter outputs a little more than 6
volts. The voltage supplies to the calc must never exceed 6 volts.
References: