Radio Theory and design

My friend Pat Pending sent me this one. It is worth a look. I would have to make some changes to build it with my materials on hand. Diode...

My first post was an op amp radio. It used a LM741 which is a 1Mhz amp. I built it with a NE5532 which is rated at 5Mhz. It was designed to ...

A slick little circuit made with 6 transistors, 2 resistors, and a transformer. It is available as an IC but what's the fun in buying a ...

10 for $5.65 0.87" OD doesn't sound bad BUT what are they and what can they be used for? The reviewers give good reviews but no o...

The TTFD was developed by the navy during WWII. It seems "Buck" Rodgers developed it in 1958. His version with info can be foun...

My antenna is a sideways flag. I have a 1.2KOhm resistor between the two blue dots. The antenna transformer is 20T:9T on a 1/2" yello...

Tuning the flag antenna pattern by adjusting the load. I plotted 100, 300, 500,700 and 900 Ohm for comparison. In the previous design 800Ohm...