Remember Kenneth Lundgren’s unidentified audio transformer, discussed earlier and pictured here? There was no identification marking, so Kenneth invited thoughts from our readers about the type of ...

You can purchase test equipment that will allow you to examine the loop gain and loop phase properties of an operating feedback loop and, that purchased equipment will deliver useful results over a ...

All-American type R-12 audio frequency transformer. Marked: "All-American / Audio Frequency Transformer / Type R-12 / Ratio - 3 to 1 / All-American Radio Corp. / Chicago". A standard audio transformer ...