Today's post reminds me of a cheesy 1930's black and white movie where this group of adventurer's lands on a remote Pacific Island and finds that the natives daily feed one of their own to this monster creature. The objective is to ward off the eating of all of them. They do not understand that in time the monster devours all of them! I guess I sense the need to feed you, the blog readers, with something new each day otherwise you will shift your interests to The National Enquirer or Fox News. Innovation! Our hobby is a like a large circus tent that has been divided into sections. One small section contains the group of homebrewers who are constantly looking for some new adventure. Perhaps it is with a project from the good old days or perhaps venturing forward with something involving leading edge technology. Yes, the rest of the tent is involved with contests and operating. Thank goodness for all those guys shouting CQ POTA as that provides source signals when the
At times we need to include some form of metering in our homebrew rigs. No, we will not be installing a Nano VNA in a transmitter. But often a current meter is needed like in a tube type amplifier. Real panel meters like the Simpson, Tripplet, GE, and Westinghouse of old are still hanging around but can be expensive especially for some specific ranges that may be needed. Yes, you can buy the Chinese ones for a $10 --but just not the look of the old-style round meters. So with a bit of meter magic I am going to share how you can take a basic 0-1ma meter of old and make it read up to 200ma (or any range) for this specific application. Enter the Meter Multiplier which is all based on simple mathematics. Basic electronic mathematics states the current entering a node equals the current leaving a node. So for our example I1 which is the source current is the same value as the sum of I2 and I3 which are leaving the node. Our 1st equation. Now by Ohms law E=IR, the voltage drop with I2 acr