Re: AM Murania Radio Receiver Question
Philip Karras <ke3fl@...>
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On Thursday, February 4, 2021, 7:57:08 PM EST, Jim, N5IB <n5ib@...> wrote:
The little TA642 AM receiver IC chip is designed to run with a very low voltage supply - for battery operated gear. It can run on just a single AA battery.
The red LED has a forward voltage drop generally from about 1.6 to 1.8 V when it's illuminated, so it maintains a steady voltage to supply the TA642.
You could do the same thing with two or three conventional silicon diodes in series, or with a 2V zener, if you could find one.
But in the QRP tradition of doing more with less, we get the required voltage regulation.... and the light we get for free!