Re: Hz overload

On Jun 26, 7:56=A0pm, "Tom Biasi" <tombiasi...@[EMAIL PROTECTED]
> wrote:
> "steve" <kvst...@[EMAIL PROTECTED]
> wrote in message
>
>
news:03b46771-e8ad-45bf-8bf9-7fdf483a12cf@[EMAIL PROTECTED]
>
> Since the 9v battery supply is quickly used up, I am using a ac
> battery eliminator/wall wart to run the Led timer.
>
> Although the eliminator provides the needed 12v to 15 v, it also
> changes the 50 hz dramatically to several khz.
>
> The khz output from the eliminator completely upsets the 555 timer
> input, so there is no timing available from with the circuit.
>
> I tried a 1000uF with several diodes placed at the eliminator=92s
> output, but there is hardly any production of dc.
>
> Thanks.
>
> Steve.
>
> Sounds like you are using a switching supply.
> The wall wart is not filtered very well.
> Also your project didn't address noise on the DC supply.
> I would suggest non-switching wall wart and clean up the output.
> I would also look into your design since it wasn't expecting noise from
a
> battery.
>
> Tom

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This project was difficult to design, so preferably it should be kept
same.

I will provide the schematic shortly.

Steve.