The converter uses no filters and is thus pretty broadbanded. All selectivity is trusted to the DB6NT converter and the Yaesu radio. The power supply is regulated by a three terminal voltage regulator, so the frequency won’t shift with input voltage fluctuations. The converter applies 13.8V to the coax line going to the antenna-mounted converter, [...]

12Vdc to 9,7.5,6 Vdc circuit

This simple converter using a Zener diode and a transistor into a 9V DC 12V DC battery power to the maximum 1A. The circuit is very simple to build, and requires only 3 electronic components, resistors, zener diodes and transistors. The 2N3055 transistors, 1N4738A Zener diode or Zener voltage and the same [...]

120 VAC Lamp Dimmer
The full wave phase control circuit below was found in a RCA power circuits book from 1969. The load is placed in series with the AC line and the four diodes provide a full wave rectified voltage to the anode of a SCR. Two small signal transistors are connected in a switch [...]