50mhz
No description available.
One Receiver
RF Cafe visitor David M. requested the scanning and posting of an article from the January 1963 edition of Popular Electronics, authored by Philip Hatfield from the Receiving Tube Department of General Electric. The article describes a straightforward design utilizing...
14W CW TRANSMITTER
A low-power two-stage FET transmitter designed for the 80-meter amateur band utilizes a Pierce crystal oscillator that does not require an output resonant circuit. A DC milliammeter can be connected across a 150-ohm resistor in the gate circuit of the...
4 Band Double Tuned Preselector
The circuit requires an RF input, which can be sourced from either a long wire or a loop antenna. The preamplifier operates within a frequency range from 550 kHz (Medium Wave) up to 30 MHz in the shortwave band. The...
Receiver/Scanner Preamp Circuit
The low-cost Mini-Circuits MAR-X series of chips provides a significant advantage for RF builders, featuring inherent 50-ohm input and output impedances essential for RF systems. An MAR-1-based receiver/scanner preamplifier is illustrated. Capacitors Ci and C2 are chip capacitors, with values...
Cyclotron II
The white feedthroughs are for connecting the RF high voltage to the D's (not shown). The copper pipe perpendicular to the main pipe serves as the vacuum line. The D's are equipped with screw posts on the side for connecting...
2 transistor fm transmitter
A pair of BC548 transistors has been utilized in this circuit. Although they are not specifically designed for RF applications, they still provide satisfactory performance. An ECM microphone from Maplin Electronics, model FS43W, has been employed. This is a two-terminal...
Simple RF Power Meter
Many beginners trying out their skill with QRP TX for the first time have to overcome many problems before they are able to come on the air. One usual complaint is that everything is working fine, but the signal is...
Circuit diagramms of the 144 SBB/RX - Receiver
To comprehend the interconnections between the following circuits, it is essential to first review the concept chapter. It is at the discretion of the user to select one or two of these circuits for personal development. The discussion begins with...
Simple receiver with microvolt sensitivity
The three-transistor circuit costs less than $10 to build, uses commonly available components, and consumes less than 10 mA from a single 9V battery. By winding coil L1 as shown, the circuit can receive signals in the 5 to 15...