A Question Regarding the Postwar Horn Battery Eliminator Circuit. | O Gauge Railroading On Line Forum

spwillsOGR Forum Member

I've been putting together the components to assemble this battery eliminator shared in an older post by gunrunnerjohn.

Question: Are the values of R1 and R2 set in stone, or could the circuit work with other values?

Thanks,

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8/1/168:40 PM

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stan2004OGR Forum Member

It's the ratio of R2:R1 that's important as per the equation for Vout in your diagram. I'm assuming your question is from availability of values? For example it's undoubtedly easier to find 47 and 220 Ohms instead of 50 and 240 Ohms. 47 and 220 will generate the same 1.5V output.

8/1/169:14 PM

gunrunnerjohnOGR Forum Member SUPPORTING MEMBERDIGITAL SUBSCRIBER

Also note that sometimes the horns work better on a slightly higher voltage.

8/1/169:32 PM

spwillsOGR Forum Member

Thanks for your replies. I've found 47 and 220 Ohm resistors. When I get my LM317 tomorrow night, I'll breadboard it up and test it.

8/1/169:50 PM

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