<p>Hi all, </p>
<p>I just finished my 555-based direction finder. It works too! It draws a constant 8.5mA during operation. I may increase the RC time constant, as the pitch is a bit high. On the other hand, it's very easy to hear. </p>
<p>Attached are a few pictures. Let me know if you have any questions about it! </p>
<p>Kyle </p>